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General Information
Symbol
Dmel\Chc4
Species
D. melanogaster
Name
FlyBase ID
FBal0020040
Feature type
allele
Associated gene
Associated Insertion(s)
Carried in Construct
Key Links
Allele class
Nature of the Allele
Allele class
Mutations Mapped to the Genome
 
Type
Location
Additional Notes
References
Nucleotide change:

G15830260A

Amino acid change:

A1082T | Chc-PA; A1082T | Chc-PB; A1082T | Chc-PC; A1082T | Chc-PD; A1082T | Chc-PE; A1082T | Chc-PF; A1082T | Chc-PG

Reported amino acid change:

A1082T

Comment:

Site of nucleotide substitution in mutant inferred by FlyBase based on reported amino acid change.

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

Amino acid replacement: A1082T.

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
Detailed Description
Statement
Reference

Mutant egg chambers show defects in microtubule organisation in the oocyte.

Chc4 mutant larval garland cells are defective in endocytosis.

Chc4 mutant pupal eyes show extra interommatidial pigment cells and misplaced interommatidial bristles. The normal number of photoreceptors, cone cells, and primary pigment cells is observed.

The retina of young Chc4 adult mutant eyes is highly disorganised. Gaps are observed between the ommatidia, and dying cells are observed. Adults kept in the dark for two weeks show mutant retina completely devoid of interommatidial pigment cells. The photoreceptor neurons are still present in the ommatidia and have well-formed rhabdomeres.

Wings from Chc4 mutants display normal morphology.

The neuromuscular junctions of homozygous Chc4 third instar larvae show similar levels of membrane uptake (dye internalisation) to controls in response to nerve stimulation. However, unlike in controls, the dye is often concentrated in subsynaptic structures, rather than the typical donut shape seen in controls. The size of the boutons is similar to wild type and no additional satellite boutons are seen.

The neuromuscular junctions of Chc4/Chc1 third instar larvae show similar levels of membrane uptake (dye internalisation) to controls in response to nerve stimulation. However, unlike in controls, the dye is often concentrated in subsynaptic structures, rather than the typical donut shape seen in controls. The size of the boutons is similar to wild type and no additional satellite boutons are seen.

Mutant testes show numerous elongated cysts but a complete absence of motile sperm. No mature individualised sperm are distinguishable. Morphology suggests a large variation in the width of sperm tails or failure of individualisation. Sperm tails show numerous bulges or blebs. Pre-individualized spermatogenic cysts are evident, though with fewer (40 as opposed to 64) axonemes than for wild type. Mature mutant cysts appear disorganised, in cross section. Extensive amounts of ground substance remains between the (otherwise quite mature) spermatids, and it is irregularly distributed. Mitochondrial derivatives (usually the minor one) are grossly distended. The cytoplasm between the mutant sperm tails is highly disorganised with a complex network of membranous tubules. Individualisation fails. Individualisation complexes are disorganised and spermatid nuclei are scattered.

Partial loss of function allele with a semi-dominant effect on viability; more males are produced at 21oC or lower.

Some adult escapers. Germline clones are viable. Hemizygous males are sterile, fertility can be restored by introduction of the construct P{CHC3}.

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

Chc[+]/Chc4 is an enhancer of visible phenotype of lqfglrs.Tag:FLAG

Chc[+]/Chc4 is an enhancer of visible | recessive phenotype of lqfFDD9

Chc4 is an enhancer of visible phenotype of fafBX3

Chc[+]/Chc4 is an enhancer of visible | recessive phenotype of fafBX3, lqfbE25

Chc[+]/Chc4 is an enhancer of visible phenotype of fafBX3, lqfbE25

Phenotype Manifest In
Enhanced by
Suppressed by
Enhancer of
Statement
Reference

Chc4 is an enhancer of wing margin phenotype of Nnd-3

Chc4 is an enhancer of wing vein phenotype of Nnd-3

Chc4 is an enhancer of wing cell phenotype of Nnd-3

Chc[+]/Chc4 is an enhancer of eye phenotype of lqfglrs.Tag:FLAG

Chc[+]/Chc4 is an enhancer of eye phenotype of lqfFDD9

Chc[+]/Chc4 is an enhancer of wing phenotype of fafBX3, lqfbE25

Chc[+]/Chc4 is an enhancer of eye phenotype of fafBX3, lqfbE25

NOT Enhancer of
Statement
Reference

Chc4 is a non-enhancer of phenotype of fafFO8

Additional Comments
Genetic Interactions
Statement
Reference

The retinal disorganisation and interommatidial pigment cell death observed in Chc4 mutant flies is suppressed in animals carrying a mutation in Nl1N-ts1 (when animals are grown at 18[o]C and then shifted to 31[o]C (once 40% through pupal development) for 6 hours).

The retinal disorganisation and interommatidial pigment cell death observed in Chc4 mutant flies is suppressed by Nfa-g62.

Expression of NFLN.Scer\UAS in the eye under the control of Scer\GAL4LL54 enhances the interommatidial cell death observed in Chc4 mutant eyes.

Expression of NECN.Scer\UAS in the eye under the control of Scer\GAL4LL54 completely suppresses the interommatidial cell death phenotype observed in Chc4 mutant flies.

Chc4/+ suppresses the notch-wing phenotype of Df(1)N-54l9/+ females. The L3 and L5 wing veins are thinner, deltas are less evident, and only 25% of the wings display smaller notches compared to 75% of Df(1)N-54l9/+ wings.

Chc4, Nnd-3 double hemizygous mutants display an enhanced wing phenotype compared to Nnd-3 single mutant wings. Loss of a great part of the wing surface and margin to extensive notches is observed, and loss of intervein tissue to vein overgrowth.

The eye defects of lqfFDD9 homozygotes are dominantly enhanced by Chc4. The fafBX3/fafFO8 phenotype is not enhanced by Chc4. The lqfbE25 fafBX3/fafBX3 mutant phenotype is dominantly enhanced by Chc4.

Xenogenetic Interactions
Statement
Reference
Complementation and Rescue Data
Comments

One copy of ChcN.4C.T:Zzzz\FLAG,T:Zzzz\TC rescues the sterility, poor viability and locomotive defects of Chc1/Chc4 mutants.

Expression of either ChcScer\UAS.P\T.T:Avic\GFP-EGFP, ChcScer\UAS.P\T.T:SV5\V5 and ChcScer\UAS.P\T.T:Hsap\MYC under the control of Scer\GAL4Act.PU rescues the reduced viability and sterility of Chc1/Chc4 females.

Expression of Chcwt.Scer\UAS under the control of Scer\GAL4hs.PB rescues the lethality of Chc4 mutant animals raised at 28[o]C.

Expression of Chcwt.Scer\UAS under the control of Scer\GAL4LL54 in Chc4 mutant adult eyes suppresses interommatidial pigment cell death.

Expression of ChcA1082T.Scer\UAS under the control of Scer\GAL4hs.PB fails to rescue the lethality of Chc4 mutant animals raised at 28[o]C.

Expression of ChcA1082T.Scer\UAS under the control of Scer\GAL4LL54 in Chc4 mutant adult eyes fails to rescue interommatidial pigment cell death.

Images (0)
Mutant
Wild-type
Stocks (2)
Notes on Origin
Discoverer

Separable from: second-site lethal mutation(s) on the chromosome.

Comments
Comments

Chc4 is sufficient for viability in males and females and fertility in females but it is not for fertility in males.

External Crossreferences and Linkouts ( 0 )
Synonyms and Secondary IDs (4)
References (17)