FlyBase Allele Report: Dmel\Fmr1[B55]

A 2.5 kb portion of the Fmr1 gene, encoding exons 2,3 and 4, and including the translational start codon and the first 59 codons, has been deleted by imprecise excision of the P{EP} element from Fmr1^EP3422.

(Inoue et al., 2002)

Mutations Mapped to the Genome

Curation Data

Type

Location

Additional Notes

References

deletion

3R:10,106,944..10,109,444 [-]

Comment:

A 2.5kb portion of the Fmr1 gene, encoding exons 2, 3, and 4, and including the translational start codon and the first 59 codons, has been deleted by imprecise excision of the P{EP} element from Fmr1^EP3422; position of mutation on reference sequence inferred by FlyBase curator based on author statement.

(Inoue et al., 2002)

Variant Molecular Consequences

Associated Sequence Data

DDBJ / EMBL / GenBank

DNA sequence

Protein sequence

UniProtKB/Swiss-Prot

UniProtKB/TrEMBL

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 ( 1 )

Disease

Evidence

References

model of autism spectrum disorder

CEA

(Bolduc et al., 2010)

model of fragile X syndrome

CEA

(Milojevic et al., 2024, Stojkovic et al., 2024, Golovin et al., 2021, Kennedy et al., 2020, Franco et al., 2017)

Modifiers Based on Experimental Evidence ( 0 )

Disease

Interaction

References

Comments on Models/Modifiers Based on Experimental Evidence ( 0 )

Disease-implicated variant(s)

Phenotypic Data

Phenotypic Class

Phenotype Manifest In

adult antennal lobe glomerulus (with Fmr1^Δ113M)

(Franco et al., 2017)

adult mushroom body beta-lobe

(Bolduc et al., 2008)

LNv neuron

(Reeve et al., 2005)

Pdf neuron close to tritocerebrum

(Gatto and Broadie, 2011)

ventral adult lateral neuron & commissure

(Reeve et al., 2005)

Detailed Description

Statement

Reference

Fmr1^B55/Fmr1^Δ113M transheterozygotes present severe decreases in smell perception in both attraction and aversion olfactory assays, as compared to controls. Fmr1^B55/Fmr1^Δ113M transheterozygotes also exhibit the following defects in olfactory lobe glomeruli activity (detected by calcium imaging experiments), despite lacking any obvious morphological defects in the glomeruli or in the associated projection neurons, as compared to controls: a significant decrease in inhibitory odor response and a reciprocal significant increase in excitatory odor response (namely to weak excitatory stimuli), a decreased specificity in odor encoding as shown by significant decreases in both Cosine and Euclidean distances between odor pairs, a broader response profile to odors, shown by a significant decrease in lifetime and population sparseness, a significant decrease in the probability of response to background, a significant increase in the correlation between glomerular odor response profile and physical distance between glomeruli in antennal lobes, and a significant decrease in odor mixture-related lateral suppression and reciprocal increase in odor mixture-related lateral excitation of glomeruli.

(Franco et al., 2017)

Homozygous Fmr1^B55 mutant flies exhibit normal short-term habituation (STH) when flies are exposed to either ethyl butyrate (EB) or CO[[2]]] for 30 minutes. In contrast, Fmr1^B55 mutant flies exhibit a complete block of the long-term habituation (LTH) that is normally seen when flies are exposed to either ethyl butyrate (EB) or CO[[2]]] for 4 days.

(Sudhakaran et al., 2014)

At day 5 post-eclosion, Fmr1^B55 mutant brains retain midline PDF tritocerebral (PDF-TRI) neurons that are not present in age-matched wild-type.

(Gatto and Broadie, 2011)

Fmr1^B55/Fmr1^B55 mutant adults display lower locomotor activity, a greater frequency of stopping for long lengths of time, greater frequency of erratic short bouts of activity, as compared to wild type. Fmr1^B55/Fmr1^B55 mutant larvae spend less time crawling than wild type. Fmr1^B55/Fmr1^B55 mutant adults tend to spend significantly less time in close physical proximity to other Fmr1^B55/Fmr1^B55 mutants than they do to wild type flies, or than wild type flies do to other wild type flies.

(Bolduc et al., 2010)

Fmr1^B55/+ mutants do not display any defects memory 1 day after either spaced or massed training, or 4 days after spaced training in a Pavlovian olfactory learning context, nor any defects in sensorimotor responses (shock reactivity, octanol avoidance, and methylcyclohexanol avoidance) as compared to wild type.

(Bolduc et al., 2010)

Fmr1^B155 mutants respond normally to odors and foot shock.

Homozygous Fmr1^B155 or Fmr1³/Fmr1^B155 transheterozygous mutants show significant defects in 1-d memory after spaced training, but not after massed training.

Homozygous Fmr1^B155 or Fmr1³/Fmr1^B155 transheterozygous mutants exhibit significant defects in olfactory learning and a β-lobe midline crossing defect.

At relatively low concentrations of cycloheximide or puromycin, 1-d memory after spaced training is significantly ameliorated in Fmr1^B155 mutants (and unaffected in wild-type), while there are no effects on 1-d memory after massed training. There is also a significant improvement in Long-Term Memory with the addition of metabotropic glutamate receptor antagonist MPEP to Fmr1^B155 mutants.

(Bolduc et al., 2008)

An ectopic collateral branch is observed on the small LNv projections in 12.5% of Fmr1^Δ113M adult brains. The posterior tract of the LNv neurons shows a defasciculation phenotype in 58% of brains.

(Reeve et al., 2005)

Homozygotes survive to adulthood with no discernible defects in morphology. Under 24hr Light:Dark (LD) cycles mutants behave as wild-type. However behaviour in constant darkness (DD) conditions was arrhythmic. Mutants lose rhythmicity within a couple of days after transfer to DD. 86% of mutants exhibit arrhythmicity for 15 days, though the remainder of flies appear to have a wild-type rhythmicity. Fmr1A population of Fmr1^B155 flies emerge from their pupal cases in a circadian-gated manner, as seen in wild-type.

(Inoue et al., 2002)

External Data

Linkouts

Interactions

Show genetic interaction network for Enhancers & Suppressors

Phenotypic Class

Enhanced by

Statement

Reference

Fmr1^B55 has abnormal memory phenotype, enhanceable by AGO1^k08121/AGO1[+]

(Bolduc et al., 2008)

Fmr1^B55 has abnormal neuroanatomy phenotype, enhanceable by Dp(2;2)C619/+

(Reeve et al., 2005)

Suppressed by

Statement

Reference

Fmr1^B55 has abnormal memory | dominant phenotype, suppressible by Drep2^ex13/Drep2^ex13

(Andlauer et al., 2014)

Fmr1^B55 has abnormal learning | dominant phenotype, suppressible by Drep2^ex13/Drep2^ex13

(Andlauer et al., 2014)

Suppressor of

Statement

Reference

Fmr1^B55/Fmr1[+] is a suppressor of abnormal memory | recessive phenotype of Drep2^ex13

(Andlauer et al., 2014)

Fmr1^B55/Fmr1[+] is a suppressor of abnormal learning | recessive phenotype of Drep2^ex13

(Andlauer et al., 2014)

Other

Statement

Reference

Fmr1^B55/Fmr1[+], cher^EPSΔ5 has abnormal memory phenotype

(Bolduc et al., 2010)

Fmr1^B55/Fmr1[+], cher^joy has abnormal memory phenotype

(Bolduc et al., 2010)

Phenotype Manifest In

Enhanced by

Statement

Reference

Fmr1^B55 has ventral adult lateral neuron & commissure phenotype, enhanceable by Dp(2;2)C619/+

(Reeve et al., 2005)

Other

Statement

Reference

Dp(2;2)C619/+, Fmr1^B55 has LNv neuron phenotype

(Reeve et al., 2005)

Additional Comments

Genetic Interactions

Statement

Reference

In contrast to either mutant alone, Drep2^ex13/Drep2^ex13, Fmr1^B55/+ double mutants do not exhibit defects in olfactory short term memory.

(Andlauer et al., 2014)

cher^joy/+; Fmr1^B55/+ or cher^EPSΔ5/+; Fmr1^B55/+ double heterozygotes display defective memory 1 day and 4 days after spaced training, but not 1 day after massed training in a Pavlovian olfactory learning context, but do not display any defects in sensorimotor responses (shock reactivity, octanol avoidance, and methylcyclohexanol avoidance) as compared to wild type.

(Bolduc et al., 2010)

At relatively low concentrations of cycloheximide or puromycin, 1-d memory after spaced training is significantly ameliorated in AGO1^k08121/+; Fmr1^B155/+ mutants (and unaffected in wild-type).

(Bolduc et al., 2008)

29% of Fmr1^B155/+; Dp(2;2)C619/+ double heterozygote brains show an ectopic collateral branch on the small LNv projections, while this phenotype is not seen in either single heterozygote. The posterior tract defasciculation phenotype phenotype is enhanced to an 85% penetrance in Fmr1^B155/+; Dp(2;2)C619/+ brains; the extent of defasciculation is greater in the double mutants and runs the entire length of the commissure.

(Reeve et al., 2005)

Xenogenetic Interactions

Statement

Reference

Complementation and Rescue Data

Rescued by

Fmr1^B55/Fmr1^Δ113M is rescued by Fmr1^+mIa

(Franco et al., 2017)

Fmr1³/Fmr1^B55 is rescued by Fmr1^+t14

(Bolduc et al., 2008)

Fmr1^B55 is rescued by Fmr1^+t14

(Bolduc et al., 2008)

Fmr1^B55 is rescued by Fmr1^+mIa

(Reeve et al., 2005)

Partially rescued by

Fmr1^B55 is partially rescued by Fmr1^+mIa

(Inoue et al., 2002)

Comments

The decreased smell perception displayed by Fmr1^B55/Fmr1^Δ113M transheterozygotes are rescued by Fmr1^+mIa.

(Franco et al., 2017)

The presence of Fmr1^+t14 rescues the long-term memory defect associated with Fmr1³ or Fmr1^B155 homozygotes and Fmr1³/Fmr1^B155 transheterozygotes.

(Bolduc et al., 2008)

Images (0)

Mutant

Wild-type

Stocks (1)

Kyoto

109026

w^*; Fmr1^B55

Notes on Origin

Discoverer

External Crossreferences and Linkouts ( 0 )

Synonyms and Secondary IDs (6)

Reported As

Symbol Synonym

Fmr1^B155

Fmr1^B55

(Bolduc et al., 2010, Bolduc et al., 2008)

dFMR1^B55

(Milojevic et al., 2024, Stojkovic et al., 2024, Haussmann et al., 2022)

dfmr1^B155

(Reeve et al., 2005, Inoue et al., 2002)

dfmr1^B55

(Golovin et al., 2021, Kennedy et al., 2020, Franco et al., 2017, Andlauer et al., 2014, Sudhakaran et al., 2014, Gatto and Broadie, 2011, Bolduc et al., 2010)

dxr^B55

(Zhang et al., 2004)

Name Synonyms

Secondary FlyBase IDs

References (16)

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