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General Information
Symbol
Dmel\shi1
Species
D. melanogaster
Name
FlyBase ID
FBal0015610
Feature type
allele
Associated gene
Associated Insertion(s)
Carried in Construct
Also Known As
shits1, shits, Shibirets1, shibirets, shibire-ts1
Key Links
Allele class
Nature of the Allele
Allele class
Mutations Mapped to the Genome
 
Type
Location
Additional Notes
References
Nucleotide change:

G15895417A

Reported nucleotide change:

G?A

Amino acid change:

G268D | shi-PA; G268D | shi-PB; G268D | shi-PC; G268D | shi-PE; G268D | shi-PF; G268D | shi-PG; G268D | shi-PH; G268D | shi-PI; G268D | shi-PJ; G268D | shi-PK; G268D | shi-PL; G268D | shi-PM; G268D | shi-PN; G268D | shi-PO; G268D | shi-PP

Reported amino acid change:

G?D

Comment:

Site of mutation reported relative to shi aa sequence.

Associated Sequence Data
DNA sequence
Protein sequence
 
 
Progenitor genotype
Cytology
Nature of the lesion
Statement
Reference

Nucleotide substitution G to A, resulting in the amino acid replacement: Gly to Asp.

Expression Data
Reporter Expression
Additional Information
Statement
Reference
 
Marker for
Reflects expression of
Reporter construct used in assay
Human Disease Associations
Disease Ontology (DO) Annotations
Models Based on Experimental Evidence ( 0 )
Disease
Evidence
References
Modifiers Based on Experimental Evidence ( 1 )
Disease
Interaction
References
Comments on Models/Modifiers Based on Experimental Evidence ( 0 )
 
Disease-implicated variant(s)
 
Phenotypic Data
Phenotypic Class
Phenotype Manifest In

actin filament & spermatid | conditional ts

adherens junction & wing cell | pupal stage | conditional - heat sensitive

garland cell & endosome

photoreceptor cell & synaptic vesicle

Detailed Description
Statement
Reference

In pupal shi1 homozygous photoreceptors, the rhabdomeres are partially degenerated while the rhabdomere and stalk segregate properly when compared to controls.

At the restrictive 37[o]C temperature, the presynaptic region of shi1-homozygous third instar larval neuromuscular junctions does not present abnormal density of autophagosome (detected as fluorescent puncta of Atg8 or Lamp in confocal microscopy images) under normal diet, nor defects in starvation-induced formation of autophagosomes, as compared to controls.

A pulse of bright white light administered to shi1 homozygous adults kept at the permissive temperature of 18[o]C, followed by a rapid transfer to the non-permissive temperature (25[o]C) results to a significant drop in the number of rhodopsin1-containing vesicles (RLVs) compared to controls.

When shi1 embryos are heat treated to the restrictive temperature immediately before wounding, the rate of wound closure is significantly slower than the rate of wound closure in wild-type and shi1 embryos at the permissive temperature of 23[o]C.

When incubated at 27[o]C, shi1/shi1 mutants are able to walk normally and maintain posture and largely normal behavior, but display some hyperactivity and uncoordinated walking, as compared with controls.

shi1/shi1 mutants display synaptic transmission defects during stimulation of the GF neural circuit and recording from the DLM, including increased likelihood of failure to respond to 1 Hz stimulus pulse, often followed by the requirement of a rest period of several seconds before being able to respond to subsequent stimulation, and greater variance in latency to response than wild type, and when shifted to temperatures of 29-30[o]C, display spontaneous seizure-like activity from the DLM followed by a loss of response to stimulation of the GF circuit, and when shifted from 29-30[o]C to 23[o]C, display spontaneous DLM seizure like activity again followed by recovery of the response to stimulation of the GF circuit; shi1/shi1 mutants also display high failure rates in response to 100 Hz stimulation, often only responding to the first stimulus in the train; display no difference in the seizure threshold (high frequency voltage required to trigger seizure) at 23[o]C, as compared to wild type.

Stimulation of boutons in shi1 animals at the restrictive temperature results in the accumulation of invaginated pits at the presynaptic membrane.

shi1/Y ; shiT:Zzzz\FLAG,T:Zzzz\4C animals at the restrictive temperature (without photo-inactivating shiT:Zzzz\FLAG,T:Zzzz\4C) show a block in membrane uptake upon stimulation of boutons compared to controls at 22[o]C and show accumulation of invaginated pits. In shi1/Y ; shiT:Zzzz\FLAG,T:Zzzz\4C animals at the permissive temperature in which shiT:Zzzz\FLAG,T:Zzzz\4C has been photo-inactivated, large membrane inclusions are seen in the boutons after stimulation. Membrane accumulations in stimulated boutons are also seen at the restrictive temperature in shi1/Y ; shiT:Zzzz\FLAG,T:Zzzz\4C animals in which shiT:Zzzz\FLAG,T:Zzzz\4C has been photo-inactivated, but accumulation of invaginated pits is not seen in this case.

shi1 mutant flies are viable and do not exhibit ERG defects at 24[o]C.

The process of apical surface flattening is severely compromised in shi1 mutant embryos at the restrictive temperature (32[o]C). The apical plasma membrane fails to flatten and retraction of the membrane protrusions does not occur.

The kinetics of cleavage furrow ingression during cellularisation are altered in mutant embryos at 32[o]C, with ingression of the single slow phase being significantly slower than wild type.

The rate of shgKI.T:Avic\GFP recovery in shi1 mutant polarising epithelial cells is virtually identical to that in wild-type flies at either the permissive (25[o]C) or restrictive (31[o]C) temperature.

shi1 mutant early embryos exhibit an absence of temperature-dependent polarisation recovery, compared to wild-type embryos, where shgKI.T:Avic\GFP recovery becomes significantly faster at higher (restrictive) temperatures. By contrast, both wild-type and shi1 late embryos show a slightly reduced half-life at a higher temperature, although the differences are not statistically significant.

shi1 mutants produce an activity-dependent reduction in excitatory post-synaptic current (EPSC) amplitude with rapid onset during train stimulation. Ultrastructural analysis performed at a restrictive temperature of 33[o]C following 20Hz stimulation shows that vesicle size is not increased in these mutants. The prevalence of internal membrane cisternae is greatly elevated in these mutants and can form large invaginations of the plasma membrane. There is a marked increase in the number of docked vesicle and active zone-associated vesicles with respect to wild-type.

shi1 mutants display a short term depression phenotype in response to train stimulation at 33[o]C.

Shifting mutant flies to the restrictive temperature for 4 hours results in a significant and specific disruption of the base of the rhabdomere. In particular, the characteristic apposed rhabdomeric membrane collapses inside the photoreceptor cytoplasm.

Stage 17 shi1 embryos grown at the restrictive temperature of 18[o]C and shifted to the permissive temperature of 29[o]C at stage 16 show defects in the transition from luminal liquid-clearance to air-filled airways.

shi1 mutant larval neuromuscular junctions stimulated intensely (10Hz, 12 minutes) while at the restrictive temperature of 30o[C] exhibit significantly impaired synaptic transmission, that progressively returns to normal at the permissive temperature. In preparations treated with 10mM MΒCD, there is also loss of EJP amplitude during stimulation at the restrictive temperature, but synaptic transmission does not recover after return to the permissive temperature. However, at the permissive temperature of 22[o]C, synaptic transmission is maintained in shi1 mutants treated with 10mM MΒCD during and after a 10Hz train for 12 minutes.

Synaptic transmission is inhibited at the restrictive temperature of 30[o]C in shi1 mutants in the presence of cholesterol-MΒCD, but recovers completely within 10 minutes of return to permissive temperature.

The addition of cholesterol through cholesterol-MΒCD or application of water-soluble cholesterol derivatives chobimalt (1mM) or cholesterol-sulfate (25mM) during the recovery period fails to rescue synaptic transmission in shi1 mutants.

Depletion of synaptic vesicles in shi1 terminals by stimulation with 90mM K[+] saline for 8 minutes at 30[o]C in the absence or presence of 10mM MΒCD results in a 67% reduction in FM1-43 uptake compared to controls, indicating a reduction of compensatory endocytosis after sterol depletion. Exocytosis is not affected.

Membrane sterol extraction in shi1 terminals at 30[oC for 12 minutes before the 10Hz train does not block recovery of synaptic transmission when preparations are subsequently subjected to a vesicle depletion-recovery protocol. Vesicular sterol extraction in shi1 terminals only during the 10 Hz train for 12 minutes at 30[o]C is sufficient to block subsequent recovery of synaptic transmission at 22[o[C.

Comparison of shi1 synapses that have been incubated in 1mM Ca[2+] HL6 saline with or without 10mM MΒCD for 20 minutes at 22[o]C reveals that there are no apparent differences in the ultrastructure of shi1 presynaptic terminals of preparations depleted of membrane sterols and controls.

Immediately after stimulation at 10Hz for 12 minutes at the restrictive temperature, both MΒCD-treated and untreated shi1 samples show complete depletion of synaptic vesicles from the terminals. To assess recovery, shi1 preparations are depleted and then allowed to recover for 20 minutes at 22o[C]. Synaptic vesicles recover in these preparations, although at lower levels than in unstimulated neuromuscular junctions. Significantly more endosomes are found in preparations depleted of vesicular sterols.

Both synaptic active zone and non-active zone endocytosis are impaired in shi1 mutants at the restrictive temperature.

Hemizygous shi1 flies are reversibly paralysed at elevated temperatures.

In contrast to wild-type controls, the amplitudes of evoked excitatory junctional potentials (EJPs) decline sharply during 0.5 Hz stimulation in shi1 mutant third instar larvae at the restrictive temperature.

shi1 embryos, shifted to the restrictive temperature at stage 11, demonstrate over-elongated dorsal trunks.

shi1 males exhibit decreased FM1-43 dye loading at the larval neuromuscular junction, compared to controls.

No detectable TR-avidin tracer internalization occurs at 29[o]C in shi1 mutant Garland cells. Vesicle endocytosis occurs at reduced rates in shi1 males at 18[o[C compared to controls.

Photoreceptors of shi1 flies grown at 23[o]C show variable photoreceptor defects, including poorly formed rhabdomeres and mild accumulations of tubulovesicular intermediates in the cell body.

shi1 mutants show a four-fold increase in fluorescence, indicating an increase Ca[2+] concentration (using a Ggal\MLCK::Rat\CamG-CaMP.1.6.Scer\UAS.T:Avic\GFP-cpEGFP indicator transgene) which suggests a defect in endocytosis at this temperature.

The levels of membrane uptake (dye internalisation) in shi1 mutant synaptic boutons in response to nerve stimulation at the restrictive temperature is significantly reduced compared to controls. Increased uptake is seen when these flies are treated with chlorpromazine.

The luminal chitin extracellular matrix is disorganised and the gap region is lost in the tracheal tubes of mutant embryos at the restrictive temperature.

shi1 flies show rapid paralysis when transferred to the restrictive temperature (30[o]C). The flies become progressively more sensitive to paralysis and need longer to recover with increasing age.

shi1 flies are completely paralysed at 38oC.

shi1 flies move their legs in response to artificial stimulus of the giant fiber neuon only at the permissive temperature (20oC) and not at the restrictive temperature (38oC).

shi1 flies completely lose synaptic transmission upon activation of the giant fiber neuron at restrictive temperatures. Indeed they lost their transient potentials at 33oC, consistent with a depletion of the vesicle pool.

shi1 mutant third instar larvae, kept at the intermediate temperature of 25oC exhibit supernumerary satellite boutons (12.5 per synapse, compared to approximately 3.1 in wild-type or 4.0 in shi1 mutants at the permissive temperature of 18oC).

When shi1 flies are pretreated at 35oC for 30 min and heat shocked for 40 min at 38oC, they show complete paralysis initially, but show a nearly complete recovery after ~30 min at room temperature.

trplninaE.T:Avic\GFP-EGFP translocation is unaffected in shi1 mutant photoreceptors, indicating that the internalisation mechanism of trplninaE.T:Avic\GFP-EGFP is dynamin-independent.

Few if any TUNEL-positive columnar cells are observed in shi1 wing discs.

When shi1 homozygous pupae are shifted from 18°C to 34°C starting at wing development stage P2B (when the first morphological signs of veins appear (FBrf0005070)), marker analysis shows disruption to adherens junctions by 30-45 minutes after shifting to 34°C. At this time, septate junctions and baso-lateral proteins are unaffected. By 3 hours after the shift, hexagonal packing of intervein cells, which usually occurs around this stage, is disrupted. However, by 6 hours after shifting to 34°C, cell free areas appear in the intervein regions and, if the animals are then shifted to 18°C, the resulting adults have holes in their wings. These phenotypes are not seen when animals are shifted to 34°C for the third instar larval stage. The window during which heat shock in these animals produces holes in adult wings is between stage P2a (when the wing begins to contract into a thin blade (FBrf0005070)) and the middle of stage P2c (before hair formation).

shi1 larvae show a release of ~50,000 quanta in response to 10 Hz stimulation at the restrictive temperature (32oC), compared to ~350,000 quanta released in wild-type larvae.

Shifting 2-day-old shi1 adults to 29oC for 11 hours results in a reduction of F-actin density in the investment cones of spermatid individualization complexes. A 16 hour heat pulse results in actin density being undetectable in these cones.

Neurotransmitter release (measured by excitatory junctional potential amplitude at the neuromuscular junction) decreases to zero 1 to 2 minutes after the initiation of stimulation at 34[o]C.

shi1 flies become paralysed at 26-27oC. shi1 larvae show a defect in endocytosis at 36oC. shi1 larvae show a stimulation-dependent decrease in excitatory junctional potential amplitude when stimulated at 10Hz at 24oC.

shi1 larvae are paralyzed when the temperature is raised to 34oC, but recover rapidly when the temperature is changed to 22oC, with larvae regaining levels of activity comparable to control strains within 5 minutes. Stimulation at 34oC leads to complete depletion of synaptic vesicles in nerve terminals of shi1 larvae. Large vesicular structures arrested in the process of pinching off from the bouton surface can be observed. This elimination of synaptic vesicles has little impact on the intracellular Ca2+ signal.

shi1 heterozygotes do not exhibit any stress-sensitivity when exposed to heat shock (90s, 30[o]C) and vortexing (10s), compared to controls.

shi1 mutants exposured to 38oC exhibit a delay before paralysis.

shi1 homozygous embryos collected at permissive temperature (25oC) for 7 h and then shifted to 34oC for another 7 hours exhibit tracheal phenotypes of differing severity. Mildly affected embryos have occasional ectopic branching and abnormal cellular projections from the tip cells. More severely affected embryos are characterized by misallocation of dorsal trunk cells into the position of transverse connectives, the dorsal branch domain, or into forming an extra loop of dorsal trunk.

Synaptic vesicle recycling is blocked at 29oC in shi1 mutants, but can proceed as normal at 18oC.

Mutant embryos shifted to the restrictive temperature of 32oC show a complete inhibition of membrane invagination in the slow phase of cellularisation. Mutant embryos that are shifted to the restrictive temperature at the beginning of fast phase do cellularise, although at a slightly slower rate than control embryos. Mutant embryos shifted to the restrictive temperature of 32oC for 20 minutes during slow phase have apical endocytic structures which are decorated with dark coated pits.

In shi1 mutants, endocytosis is completely blocked at 30oC (restrictive temperature) by the dysfunction of dynamin, which (under light stimulus) results in the depletion of synaptic vesicles and a concomitant increase in the surface area of the nerve terminal (to approximately double the diameter). When flies are returned to 20oC (permissive temperature), the nerve terminal fills with synaptic vesicles through rapid endocytic reformation, and the surface area of the nerve terminal returns to a normal size.

Bigger cisternal and tubular structures of around 150nm are observed in shi1 pre-synaptic terminals compared to wild-type.

Recovery time from paralysis after heat treatment is strongly proportional to the length of heat treatment in shi1 flies.

At 22oC, hemizygous males show odor-evoked transients identical to those of wild-type flies. At the restrictive temperature, synaptic transmission is blocked.

Exposure of shi1/Y males to the non-permissive temperature for 6 hours does not have any obvious effect on actin in actin cones or organisation of individualisation complexes in the testis.

When nerves of shi1 mutants are subjected to tetanic stimulation at the restrictive temperature, the EJP amplitude steadily declines to zero after 500 s.

The heartbeat of homozygous or hemizygous pupae is increasingly slower and more arrhythmic than wild type with increasing temperature. The severity of the phenotype increases uniformly as the temperature rises. The phenotype is recessive. The mutant heart generates a signature double-peak per beat on an electrocardiogram in contrast to wild type which shows a single peak per beat. Injection of norepinephrine does not accelerate the heart rate (in contrast to wild type).

All homozygous females and hemizygous males stop moving within 1 minute after transfer to 30oC. Immediately after transfer to 30oC, the mutant adults show extensive activity, such as intense wing buzzing, before they become paralysed. The temperature-sensitive paralysis is reversible upon transfer to 22oC; the flies regain their activity and start to walk within 1 minute.

Stimulation of mutant larval synapses at 3Hz for 10 minutes results in a clear decline in synaptic transmission in mutant larvae at the restrictive temperature (32oC).

Excitatory synaptic currents (ESCs) occur at 25oC in mutant embryos, but not at 32oC.

When synaptic current evoked by tetanic nerve stimulation at the permissive temperature, initial amplitude and steady state current amplitudes are indistinguishable from wild-type. At the non-permissive temperature, a decline of synaptic current amplitude is seen during 400 s 10 Hz tetanic stimulation of neuromuscular junctions, reducing to a complete absence of synaptic current after about 350 stimuli. Endocytosis and vesicle translocation from readily releasable pools (RRP) to reserve pools (RP) is also blocked.

shi1 dorsal longitudinal muscle neuromuscular synapses show a clear activity-dependent reduction in synaptic current at 33[o]C when stimulation frequency is 1Hz (wild-type synapses at 33[o]C, and mutant synapses at 20[o]C show constant-amplitude synaptic currents at this stimulation frequency). At a stimulation frequency of 50Hz at 33[o]C, shi1 synapses show a more rapid and pronounced activity-dependent reduction than wild-type synapses. A clear difference between wild-type and mutant synapses is seen in the second response to a 50Hz stimulus train.

Neuromuscular synapses of the intracoxal lateral levator muscle (ICLM) show a fast synaptic fatigue phenotype at a stimulation frequency of 50Hz at 33[o]C in shi1 mutants. The ICLM motor axons are nearly devoid of synaptic vesicles at 33[o]C.

Following exposure of shi1 flies to the non-permissive temperature of 30oC retinula termini show a marked depletion of synaptic vesicles. In an assay for larval motility, shi1 mutants performed significantly less well than wild-type larvae. In locomotor assays testing olfactory response to propionic acid, shi1 mutants perform significantly less well than wild-type larvae.

Reductions in shi function from 41-47 hours after puparium formation in developing retinas result in the loss of primary pigment cells and the development of supernumerary cells that resemble secondary pigment cells. Reductions in shi function (following a heat pulse) in the developing wing disc result in adults which show only mild vein thickenings at the marginal termini of longitudinal veins 3, 4 and 5.

shi1/shi20 flies are paralysed at a temperature of 26oC.

A slowing of dorsal longitudinal flight muscle synaptic current kinetics is seen at 33oC.

An accumulation of endocytotic membrane is seen at the active zone of the coxal synapse in homozygous flies exposed to 29oC.

In ERG assay, mutants lose the on/off transients at 38oC. Recovery of transients at 20oC is slower than for Syx1A3-69.

Use of a fluorescent Ca-sensitive dye to monitor presynaptic Ca dynamics in mutants shows the conditional blockade of synaptic vesicle recycling. The absence of synaptic vesicles may interfere with the function of presynaptic Ca channels.

Mutants shifted to 29oC at the time of microchaetae precursor determination (14-10 hours APF) differentiate a large number of extra microchaetes, phenotype is more severe in medial than lateral areas of the thorax. The mutant phenotype results from the development of an excess of neural precursors at the expense of epidermal cells. Clones generated during the first and second larval stages present a strong neurogenic phenotype and bristles along the border can be either wild type or mutant. Occasionally a mutant bristle can be found adjacent to a wild type one. Mutant cells are defective in both sending and receiving the lateral signal.

Nerve-impulse evoked transmitter release is completely lost in larval muscles at the restrictive temperature of 32oC.

High temperature stimulation depletes synaptic vesicles in larval type 1b terminals. In these vesicles dynamin is membrane-associated and is concentrated sharply at specific hot spots on presynaptic plasmalemma. These hot spots may correspond to active zones for synaptic vesicle retrieval.

Retinula cells are completely depleted of synaptic vesicles after 30 seconds at 29oC in the light adapted condition.

Sub-anaesthetic concentration of carbon dioxide specifically suppresses the temperature sensitive paralytic phenotype. Sub-anaesthetic concentration of carbon dioxide also rapidly reverses paralysis induced at the restrictive temperature. The effect depends on the absolute concentration of CO2 rather than the ratio with oxygen.

The delivery of an electrical buzz (50-400 msec) to the brain has no significant effect on shi1 mutant flies.

Synaptic vesicles are depleted at nonpermissive temperatures.

Embryonic neoplastic mutant.

Depletion of synaptic vesicles after stimulation at elevated temperatures: temperature sensitive cessation of synaptic vesicle recycling, consequent vesicle depletion and behavioural paralysis. Synaptic vesicle membrane proteins are transferred to plasma membrane by exocytosis but are not retrieved. Vesicle recycling after the block can occur without extracellular calcium or the highly elevated intracellular calcium levels associated with exocytosis. Crude BWSV appears to induce calcium-independent exocytosis at motor terminals.

Prolonged heat treatments of shi1 small-patch mosaics at different pupal stages does not prevent the establishment of central projections characteristic of the various sensory cell types. However, shi1 neurons heat-pulsed during the initial or final 16% of pupal development are not able to initiate reflex behaviour. Heat treatment of adult shi1 mosaics blocks the sensory bristle reflex behaviour, either for several days, or permanently in flies older than 4-5 days of age.

Two stocks carrying shi1 are available, one carrying w+ and one carrying w-. The ERG response of these two stocks does not change when flies are cooled to 11oC. However the on- and off-transients are lost when cooled below 24oC in the w+ stock, this reappears when warmed again above 24oC. Raising the temperature first delays the on-transient and then abolished both the on- and off-transients. Visual pigment absorbence does not differ between the stocks.

Within clones the muscle phenotype is independent of the motoneuron or muscle attachment site genotype. Control of the induced muscle phenotype evidently lies within the muscle itself.

Not susceptible to p-Cresol.

Coated pits in the photoreceptors seem to extend on stalks and do not form coated vesicles even in flies maintained at 18oC.

Homozygotes are paralysed at 27oC.

Only 2% of prepupae subjected to a 6 hour pulse of 29oC at ages ranging from a time equivalent to 0 to 11 hours after puparium formation at 25oC (AP25) survive to eclosion, in contrast to 66% survival in pupae subjected to a 6 hour pulse of 29oC at 12 to 15 hours AP25, and 25% survival for pupae subjected to a 6 hour pulse of 29oC at 16 to 26 hours AP25. The basitarsi of the second legs of hemizygous males subjected to a 6 hour pulse of 29oC at 7 hours AP25 have an average of 370 bristles (4.9 times the wild-type number). Hair density on the femur decreases as bristle density increases. Basitarsal bristle number then declines as the age at which the pupae are heat shocked increases, but remains elevated until heat shock at 11 hours AP25. For flies heat shocked between 11 to 28 hours AP25, many bristles are missing from the pattern, with a brief partial recovery, to an average of 43 bristles per basitarsus, for heat shock between 17 and 20 hours AP25. For flies heat shocked between 15 to 16 hours AP25, most bristles on the basitarsus have two shafts and no socket or bract. For flies heat shocked between 27 to 31 hours AP25, some bractless bristles develop bracts.

The basitarsi of the second legs are reduced in length and increased in width in flies derived from white prepupae aged for 9 hours and then exposed to the restrictive temperature of 29oC for 6 hours. The total number of bristles on the basitarsi of the second legs is increased and the number of bractless bristles is reduced. Bristles are no longer consistently aligned in rows. The bristle-less zone of sparse hairs between bristle rows 1 and 8 is narrower than normal.

Hemizygous flies generally do not survive.

The endosomal compartment is no longer apparent in garland cells of homozygous adults exposed to 29oC for 10 minutes. The labyrinthine channels of the garland cells are considerably elongated in these flies and many coated pits have accumulated on them. The tubules of the endosomal compartment gradually disappear after 7 minutes at 29oC, and by 12 minutes at 29oC the vacuoles of the endosomal compartment also disappear.

shi1 neurons actively endocytose fluorescein-labelled dextran or horseradish peroxidase when cultured at 22oC, however, endocytosis is inhibited by a 15 minute heat pulse (30oC) in cultured shi1 neurons. This block in endocytosis is reversed by a high concentration of external cations or by returning the cells to a temperature of 20oC.

Exposure to heat pulses determines the temperature sensitive period 0 to 5 hours after gastrulation. Heat pulses given 1-3 hours after gastrulation delete the ventral epidermis. Pulses 3-5 hours after gastrulation cause large holes in the ventral epidermis, dorsal and lateral epidermis are normal. Mouth parts may evert. Heat pulse at 2-4 hours after gastrulation causes only the filzkorper and trachea to develop of all epidermal structures. The cell membranes of cells in the neurogenic region exhibit extracellular packets of vesicles lying between the cells and the overlying vitelline membrane.

Endocytosis in the oocyte is reversibly blocked at the stage of pit formation in shi1 females; after 10 minutes at 29oC, endocytosis is blocked and there is a build-up of coated pits along invaginations of the plasma membrane and the endosomal compartment disappears. If the temperature is then lowered to 19oC, a synchronised wave of endocytosis occurs.

Neuromuscular synaptic terminals, sensory retinula cell synaptic terminals and central thoracic ganglion and optic lobe medulla synaptic terminals are essentially the same as wild-type at 19oC, but at 30oC a number of abnormal features are seen in shi1 flies. These include variable amounts of vesicle depletion, a variable increase in membranous structures, and the accumulation of many pit-like structures on the plasma membrane ("collared pits"). The pit-like structures consist of a spherical head portion, and a cylindrical neck portion which is surrounded by a cytoplasmic dense "collar".

The following developmental consequences are seen after heat pulses at the restrictive temperature for one to several hours at different stages of

development (shi1):

temperature-sensitive period: 1.5-3 hr

developmental phenotype: loss of pole cells

temperature-sensitive period: 3-4 hr

developmental phenotype: fusion of cell membranes

leading to syncytium

temperature-sensitive period: 5-12 hr

developmental phenotype: disorganized proliferation of

cells leading to transplantable tumorous masses

temperature-sensitive period: late third instar

developmental phenotype: stubby legs; joints missing;

temperature-sensitive period: 12 hr heat pulse

developmental phenotype: clipped wings

temperature-sensitive period: 48 hr before pupariation

developmental phenotype: eye scar (loss of pigment

cells and cone cells). The later the heat pulse, the more anterior the

position of the scar on eye

temperature-sensitive period: pupariation to pupation

developmental phenotype: animals die and fail to

undergo pupation

temperature-sensitive period: 14-24 hr after pupariation

developmental phenotype: supernumerary microchaetae on

head and thorax; the temperature-sensitive period for each bristle site

precedes the final cell

division of bristle precursor; loss of macrochaetae

on head and thorax.

Disruption of giant-fiber pathway development

(Hummon and Costello, 1987). Reduced numbers of dorsal-longitudinal flight

muscles (Hummon and Costello,

1988)

temperature-sensitive period: 24-36 hr after pupariation

developmental phenotype: loss of head and thoracic

microchaetae; supernumerary

abdominal macrochaetae and microchaetae

temperature-sensitive period: 28-42 hr after pupariation

developmental phenotype: loss of abdominal

macrochaetae and microchaetae

temperature-sensitive period: 32-48 hr after pupariation

developmental phenotype: loss of abdominal

microchaetae

temperature-sensitive period: 48 hr after pupariation

developmental phenotype: scimitar-shaped bristles

temperature-sensitive period: adult

developmental phenotype: eggs fail to mature

temperature-sensitive temperature of adult paralysis: 29oC

temperature of larval paralysis: 29oC

temperature causing developmental defects: 29oC

viability of allele over deficiency: weak

External Data
Interactions
Show genetic interaction network for Enhancers & Suppressors
Phenotypic Class
Enhanced by
Statement
Reference

shi1 has paralytic | heat sensitive phenotype, enhanceable by Ppt1A179T

shi1 has paralytic | recessive | heat sensitive phenotype, enhanceable by BicDr5/BicD[+]/BicDr5

shi1 has abnormal neurophysiology | heat sensitive phenotype, enhanceable by SynjLY/Df(2R)X58-7

NOT Enhanced by
Statement
Reference

shi1 has abnormal neurophysiology | heat sensitive phenotype, non-enhanceable by Snap25ts

shi1 has paralytic | heat sensitive phenotype, non-enhanceable by sesBorg

NOT suppressed by
Statement
Reference

shi1 has abnormal neurophysiology | heat sensitive phenotype, non-suppressible by Snap25ts

shi1 has paralytic | heat sensitive phenotype, non-suppressible by sesBorg

Enhancer of
Statement
Reference

shi[+]/shi1 is an enhancer of paralytic | conditional phenotype of sesB1

shi1 is an enhancer of visible | recessive phenotype of lqfFDD9

shi1/shi1 is an enhancer of visible phenotype of fafFO8/fafBX3

NOT Enhancer of
Statement
Reference

shi1 is a non-enhancer of abnormal neurophysiology | heat sensitive phenotype of Snap25ts

Suppressor of
Statement
Reference

shi1/shi1 is a suppressor | partially of bang sensitive phenotype of jusiso7.8

shi1 is a suppressor of abnormal neuroanatomy | heat sensitive phenotype of comt4

NOT Suppressor of
Statement
Reference

shi[+]/shi1 is a non-suppressor of bang sensitive phenotype of parabss1

shi1/shi2 is a non-suppressor of bang sensitive phenotype of parabss1

shi1 is a non-suppressor of abnormal neurophysiology | heat sensitive phenotype of Snap25ts

Other
Phenotype Manifest In
Enhanced by
Statement
Reference

shi1 has wing cell | adult stage | heat sensitive phenotype, enhanceable by dgo[+]/dgo380

shi1 has wing cell | adult stage | heat sensitive phenotype, enhanceable by Vangstbm-6/Vang[+]

shi1 has wing cell | adult stage | heat sensitive phenotype, enhanceable by pk[+]/pk1

shi1 has wing cell | adult stage | heat sensitive phenotype, enhanceable by stan[+]/stan3

shi1 has wing cell | adult stage | heat sensitive phenotype, enhanceable by pk[+]/pksple-1

shi1 has wing cell | adult stage | heat sensitive phenotype, enhanceable by Vangstbm-D/Vang[+]

shi1 has actin filament & spermatid | conditional ts phenotype, enhanceable by ctpins1

shi1 has actin filament & spermatid | conditional ts phenotype, enhanceable by ctpDIIA82

shi1 has presumptive embryonic/larval tracheal system | heat sensitive phenotype, enhanceable by awdj2A4/awd[+]

shi1 has dorsal trunk primordium | heat sensitive phenotype, enhanceable by awdj2A4/awd[+]

Suppressed by
Statement
Reference

shi1 has ommatidium | adult stage | conditional phenotype, suppressible by Pld3.1/Pld3.1

shi1 has eye photoreceptor cell & synaptic vesicle phenotype, suppressible by EndoAEP927/Scer\GAL4[-]/endoAEP927

Enhancer of
Statement
Reference

shi[+]/shi1 is an enhancer of eye phenotype of cathD1

shi1/shi1 is an enhancer of eye phenotype of fafFO8/fafBX3

Suppressor of
Statement
Reference

shi1 is a suppressor of synapse | heat sensitive phenotype of comt4

shi1 is a suppressor | partially of ommatidium phenotype of rdgC306

NOT Suppressor of
Statement
Reference

shi1 is a non-suppressor of rhabdomere R4 phenotype of norpA7

shi1 is a non-suppressor of rhabdomere R5 phenotype of norpA7

shi1 is a non-suppressor of rhabdomere R6 phenotype of norpA7

shi1 is a non-suppressor of eye phenotype of norpA7

shi1 is a non-suppressor of retina phenotype of norpA7

shi1 is a non-suppressor of rhabdomere R1 phenotype of norpA7

shi1 is a non-suppressor of rhabdomere R2 phenotype of norpA7

shi1 is a non-suppressor of rhabdomere R3 phenotype of norpA7

Other
Statement
Reference

Scer\GAL4[-], EndoAEP927/endoAEP927, shi1 has eye photoreceptor cell & t-bar phenotype

Scer\GAL4[-], EndoAEP927/endoAEP927, shi1 has eye photoreceptor cell & clathrin-coated vesicle phenotype

Scer\GAL4[-], EndoAEP927/endoAEP927, shi1 has eye photoreceptor cell & epithelial glial cell phenotype

Additional Comments
Genetic Interactions
Statement
Reference

Homozygosity for either PldnΔ1 or Dysbe01028 does not significantly affect the total quanta release during neurotransmission across shi1 homozygous wandering third instar larval neuromuscular junctions at the restrictive 32[o]C temperature.

The abnormal drop in the number of rhodopsin1-containing vesicles (RLVs) observed upon a pulse of bright white light administered to shi1 homozygous adult flies, that have been kept at the permissive temperature of 18[o]C, and followed by a rapid transfer to the non-permissive temperature (25[o]C) is not observed when the shi1 mutant allele is combined with Pld3.1 in homozygous state.

shi1/shi1 does not rescue the bang sensitive phenotype of eas2/eas2 or parabss1/parabss1 mutants at 23[o]C, but if incubated for 3 minutes at 26[o]C or 27[o]C immediately before testing, partially rescues the bang sensitive phenotype of eas2/eas2 or parabss1/parabss1 mutants.

shi1/shi1, eas2/eas2 double mutants exhibit defects in synaptic transmission, as shown by significantly reduced response rate to GF circuit stimulation at 100 Hz; and show seizure-like activity in the DLM and loss of GF circuit responsiveness after temperature shift to 29[o]C.

shi1/+ or shi1/shi1 does not significantly rescue the bang sensitive phenotype of parabss1/+ mutants at 23[o]C.

shi1/shi1 partially rescues the bang sensitive phenotype of sdaiso7.8/sdaiso7.8 mutants both at 23[o]C and when incubated at 26[o]C or 27[o]C before testing.

shi1/shi1, sdaiso7.8/sdaiso7.8 double mutants exhibit synaptic transmission defects upon stimulation of the GF circuit, showing a failure to respond to a proportion of 1 Hz stimulation pulses.

Vps261, shi1 double mutants raised at 18[o]C and shifted at eclosion to 24[o]C exhibit suppression of the loss of ERG amplitude found in Vps261 single mutants at day 4 in 12-hour light/dark cycles.

shi1-Ppt1A179T double mutants paralyze significantly faster when shifted to 27[o]C than do shi1 single mutants.

Boutons in the NMJs of shi1, Syngr1 mutant larvae have an increased synaptic vesicle diameter following a high K[+] shock compared with shi1, SyngrPE controls. The average diameter is comparable to that seen in Syngr1 mutants before K[+] stimulation. The boutons contain a significantly greater number of endocytic cisternae (diameter >200nm) compared with controls. Synaptic vesicle density is reduced compared with controls.

shi1;; Snap25ts double mutants display a short term depression phenotype in response to train stimulation at 33[o]C, as in both single mutants.

The time taken for shi1 flies to be paralysed on shifting to the restrictive temperature is significantly decreased, while time needed for recovery for these mutants on returning to the permissive temperature is significantly increased in a BicDr5/+ genetic background.

shi1; stmA1 double mutants are synthetically lethal. No double homozygous female third instar larvae can be recovered, indicating that lethality occurs at the second instar stage or earlier. In contrast, shi1/y; stmA1/stmArev499 males can be recovered at third instar at a very low frequency at 16[o[C, before they also die at an early pupal stage.

shi1; stmA1/stmArev499 males exhibit decreased FM1-43 dye loading at the larval neuromuscular junction, compared to controls. However, the double mutant exhibits the same level of loading as in shi1 single mutant males.

Vesicle endocytosis occurs at reduced rates in shi1; stmA1/stmArev499 males at 18[o[C compared to controls, although there is no significant difference between shi1;y and shi1/y; stmA1/stmArev499 mutants.

A shi1 mutant background enhances by more than 10-fold the level of vacuolar change in cathD1 mutant retina.

A shi1 background at 23[o]C does not suppress the rhabdomere defects caused by expression of PldScer\UAS.cRa under the control of Scer\GAL4GMR.PF.

shi1/flowerDB25 and shi1/flowerDB56 mutants are synthetic lethal.

Expression of ChcN.4C.T:Zzzz\FLAG,T:Zzzz\TC partially suppresses the loss of membrane internalisation seen in shi1/Y mutant flies at the restrictive temperature.

shi1/+ enhances the increase in total bouton number and satellite bouton number at the neuromuscular junction that is seen in nwk1/nwk2 larvae.

At the restrictive temperature, evoked release is abolished in shi1; cpxSH1 double mutant animals. The elevated miniature excitatory junctional potential frequency observed at the permissive temperature is eliminated in the double mutant.

shi1; Df(3R)Hsp70A, Df(3R)Hsp70B mutants show a higher sensitivity to pretreatment at 35oC for 30 min followed by 40 min at 38oC than shi1 flies. The double mutants show higher levels of paralysis and fail to recover, even 24 hours after the heat shock.

The formation of holes in wings due to temperature shift of shi1/shi1 animals during pupal stages is mildly enhanced by stan3/+, moderately enhanced by dgo380/+, Vangstbm-6/+ or pk1/+ and strongly enhanced by pksple-1/+ or Vangstbm-D/+.

shi1; synjLY/Df(2R)X58-7 larvae show a larger decrease in the release of quanta in response to 10 Hz stimulation at 32oC (~18,000) compared to shi1 larvae (~50,000).

The F-actin density in the investment cones of spermatid individualization complexes is further decreased following a heat pulse of 11 hours in ctpins1, shi1 and ctpDIIA82, shi1 double mutants compared to shi1 single mutants.

Heterozygous sesB1; shi1 mutants exhibit significantly greater paralysis time after heat shock (90s, 30[o]C) and vortexing (10s) compared to controls.

The tracheal system phenotypes of shi1 homozygous embryos (collected at the permissive temperature (25oC) for 7 h and then shifted to 34oC for another 7 hours) are dominantly enhanced by awdj2A4 : the penetrance of the most severe phenotypic class is increased from 1.2% to 33.2% by the presence of awdj2A4/+. (Note, these sever phenotypes are never observed in awdj2A4/+ embryos raised under the same conditions).

Flies with endoAEP927;shi1 eyes suffer a depletion of functional synaptic vesicles when raised to 29oC for 15 minutes to the same extent as flies with single shi1 mutant eyes. After 30 minutes of recovery time at 18oC following the 15 minutes at 29oC, endoAEP927;shi1 photoreceptor terminals show an increased number of capitate projections, which are invaginations of epithelial glia, compared to shi1 single mutants. Additionally, membrane sheets emerging from near the pedestal of the T-bar ribbon of photoreceptor terminals persist for longer during the recovery time in endoAEP927;shi1 double mutants than shi1 single mutants. There is less synaptic vesicle depletion in endoAEP927;shi1 mutant terminals following exposure to 29oC than in shi1 terminals. These vesicles appear clustered and electron dense in the double mutants, similar to their appearance in endoAEP927 single mutants. In endoAEP927;shi1 mutants, free vesicles persist during exposure to 29oC, while in shi1 mutants, vesicles do not remain coated at this temperature.

Rab5N142I.Scer\UAS mutants, expressed with Scer\GAL4hs.PS in shi1 mutants, induces enlargement of vesicles. These vesicles disappear when flies are kept at 30oC (shi1 restrictive temperature). When flies are returned to 20oC (shi1 permissive temperature), enlarged vesicles, along with normal-sized vesicles are re-formed in the terminal.

awdMSF15 only slightly reduces the temperature threshold for paralysis in shi1 flies.

shi1/Y jar1 double mutant males exposed to the non-permissive temperature for shi1 show a dramatic reduction in the number of individualisation complexes per testis.

shi1/Y ; mlenap-ts1/mlenap-ts1 animals have near-normal heartbeats at temperatures from 20-35oC, but have an abnormal heart rate at 37oC. shi1/Y ; mlenap-ts1/+ animals have near-normal heartbeats at temperatures from 25-37oC, but have an abnormal heart rate at 20oC. shi1/shi1 ; mlenap-ts1/mlenap-ts1 animals have significantly slower than normal heart rates at all temperatures but the beat is normally rhythmic. shi1/shi1 ; mlenap-ts1/+ animals have significantly slower and less rhythmic than normal heart rates at several temperatures.

Retinal axon terminals in comt4 shi1 are devoid with synaptic vesicles and show an increase in larger vacuolar-type structures.

The addition of shi1 to norpA7 mutants partially rescued the light dependant retinal degeneration phenotype.

The lqfFDD9 phenotype is enhanced if the flies are also homozygous for shi1. The fafBX3/fafFO8 phenotype is slightly enhanced if the flies are also homozygous for shi1.

rdgC306,shi1 mutants exposed to 10 minutes of blue light followed by 4 days of dark incubation show a partial rescue of the Deep Pseudopupil phenotype seen in rdgC306 flies alone.

Thirty-seven percent of shi1; Scer\GAL4GMR.PF CblDv.Scer\UAS wings exhibit an ectopic vein phenotype, moreso than in Scer\GAL4GMR.PF CblDv.Scer\UAS mutants.

NAx-59b shi1 double mutant clones in the thorax induced during the larval stage at the restrictive temperature present a strong neurogenic phenotype (excess of bristles), at the permissive temperature they are completely devoid of bristles. Homozygous Nl1N-ts1 clones exhibit a strong neurogenic phenotype, all bristles at the border of the clone are mutant. Nl1N-ts1 shi1 clones also exhibit a strong neurogenic phenotype, 7% bristles along the clone border are wild type. Occasionally adjacent wild type and mutant bristles are seen.

The lethality of shi1, stnA7 double mutants is complete. dnc1, parats1 and dnc1, shi1 double mutants show no more severe effect than either paralytic mutant alone. stnA15 shows no interaction with shi1.

Xenogenetic Interactions
Statement
Reference
Complementation and Rescue Data
Comments

The paralysis phenotype is rescued by shit15 : shi1 flies carrying shit15 are paralysed at 30-35oC.

Images (0)
Mutant
Wild-type
Stocks (7)
Notes on Origin
Discoverer

Grigliatti.

Comments
Comments

Used to load terminal boutons with FM1-43 fluorescent dye, after depletion of synaptic vesicles at 34oC.

Does not suppress the Sh behavioural phenotype.

Turnover of the photoreceptor membrane in shi1 mutant flies has been studied using electron microscopy.

Order of temperature sensitivity in the hemizygous condition: shi4 > shi21 > shi1 > shi2. Order of temperature sensitivity in the homozygous condition: shi21 = shi1 > shi4 >= shi2. Order of temperature sensitivity of heteroallelic combinations: shi2/shi21 = shi1/shi21 >= shi4/shi21 > shi1/shi2 = shi1/shi4 >> shi2/shi4.

The shi1 mutation has been used to study the process of synaptic vesicle recycling, which is normal at 19oC but completely blocked at 29oC in shi1 flies. Studies of the ultrastructure of retinula cells during recovery from exposure to 29oC in these flies indicate that two distinct pathways are involved in the recycling of synaptic vesicles within a single synapse.

External Crossreferences and Linkouts ( 0 )
Synonyms and Secondary IDs (24)
Reported As
Symbol Synonym
Shibirets1
l(1)shits1
l(1)shibirets1
shits1
(González-Méndez et al., 2020, Zhang et al., 2020, Bajur et al., 2019, Iyer et al., 2019, Kim et al., 2019, Ogi et al., 2019, Skouloudaki et al., 2019, Ressurreição et al., 2018, Chen et al., 2017, Kamalesh et al., 2017, Zhou et al., 2017, Soukup et al., 2016, Thakur et al., 2016, Hunter et al., 2015, Kroll et al., 2015, Zang et al., 2015, Kasprowicz et al., 2014, Wang et al., 2014, Bilioni et al., 2013, Winther et al., 2013, Hill et al., 2012, Stevens et al., 2012, Callejo et al., 2011, Stümpges and Behr, 2011, Uytterhoeven et al., 2011, Grygoruk et al., 2010, Kuromi et al., 2010, Vijayakrishnan et al., 2010, Katsuki et al., 2009, Yao et al., 2009, Belenkaya et al., 2008, Kasprowicz et al., 2008, O'Connor-Giles et al., 2008, Behr et al., 2007, Kicheva et al., 2007, Korolchuk et al., 2007, Rikhy et al., 2007, Su et al., 2007, Callejo et al., 2006, Dickman, 2006, Dickman et al., 2006, Huang et al., 2006, Meyer et al., 2006, Rives et al., 2006, Seto and Bellen, 2006, Ghosh-Roy et al., 2005, Roegiers et al., 2005, Verstreken et al., 2005, Belenkaya et al., 2004, Han et al., 2004, Kruse et al., 2004, Kuromi et al., 2004, Torroja et al., 2004, Wang et al., 2004, Wu et al., 2004, Fabian-Fine et al., 2003, Guha et al., 2003, Ranganathan, 2003, Rikhy et al., 2003, Burnette and Hirsh, 2002, Chen et al., 2002, Fetchko et al., 2002, Guichet et al., 2002, Stewart, 2002, Stewart et al., 2002, Verstreken and Bellen, 2002, Waddell, 2002, Hsu and Chiba, 2001, Johnson et al., 2001, Kitamoto, 2001, Macleod et al., 2001, Narayanan and Ramaswami, 2001, Waddell and Quinn, 2001, Zars et al., 2001, Cadavid et al., 2000, Delgado et al., 2000, Entchev et al., 2000, Estes et al., 2000, Kiselev et al., 2000, Parks et al., 2000, Phillips et al., 2000, Robertson et al., 2000, Kuromi and Kidokoro, 1999, Roos and Kelly, 1999, Grant et al., 1998, Koenig et al., 1998, Kuromi and Kidokoro, 1998, Ranjan et al., 1998, Umbach et al., 1998, Seugnet et al., 1997, Umbach and Gundersen, 1997, Estes et al., 1996, Ikeda and Koenig, 1996, Kramer and Phistry, 1996, Krishnan et al., 1996, Sturtevant et al., 1996, van de Goor and Kelly, 1996, Gass et al., 1995, Parks et al., 1995, Pavlidis and Tanouye, 1995, Ramaswami et al., 1995, van de Goor et al., 1995, Capdevila et al., 1994, Lilly et al., 1994, Mechler, 1994, Ramaswami et al., 1994, Tabata and Kornberg, 1994, Hummon and Costello, 1993, Petrovich et al., 1993, Truman et al., 1993, van der Bliek and Meyerowitz, 1991, Kim and Wu, 1990, Koenig and Ikeda, 1990, Masur et al., 1990, Poodry, 1990, Gateff and Mechler, 1989, Ganetzky, 1984, Kosaka and Ikeda, 1983, Poodry, 1980)
shibirits
Secondary FlyBase IDs
    References (232)