FlyBase Allele Report: Dmel\Rab8[1]

Rab8¹ homozygous clone cells within a mosaic follicular epithelium deposit basement membrane components on both basal and apical extracellular sides, as compared to only on the basal side in controls.

(Devergne et al., 2017)

Rab8¹/Rab8² mutants show pharate lethality.

Rab8¹/Rab8^B229 mutants show pharate lethality.

All the tested trans-heterozygous allelic combinations of Rab8¹ mutants display synaptic overgrowth, characterized by significant increase in synaptic bouton number of up to 100% relative to wild-type. The synaptic overgrowth is highly penetrant affecting every neuromuscular junction (NMJ) observed including both muscles 6/7 and 4.

In addition to elevated bouton number, Rab8¹/Rab8^B229 mutants also have a significant increase in neuromuscular junction length, branching, and satellite bouton number, with reduction in synaptic bouton size.

Postsynaptic expression of Rab8^Scer\UAS.cWa under the control of Scer\GAL4^Mhc.PW rescues the increased synaptic bouton number phenotype at muscle 6/7, but not synapse length at neuromuscular junctions in Rab8¹/Rab8^B229 mutants.

Synaptic bouton number or length in muscle 4 is not rescued by muscle expression of Rab8^Scer\UAS.cWa.

Rab8¹/Rab8^B229 mutants display a clear reduction in both fast and slow recycling endosomes at both the NMJ and in motor neuron cell bodies in the larval ventral nerve cord. Upon ultrastructural analysis of mutant synapses, accumulation of large endosome-like, intermediary structures within synaptic boutons are observed. The observed structures, however, are dissimilar and unlikely synaptic vesicles as they are not released, because there is no increase in quantal size during electrophysiological analysis. On the contrary, Rab8¹/Rab8^B229 mutants show decreased quantal size compared with wild-type. These structures are similar to autophagosomal intermediates and they are never observed in wild-type animals.

(West et al., 2015)

External Data

Linkouts

Interactions

Show genetic interaction network for Enhancers & Suppressors

Phenotypic Class

Suppressed by

Statement

Reference

Rab8¹/Rab8^B229 has abnormal neuroanatomy | third instar larval stage phenotype, suppressible by tkv⁷/tkv[+]

(West et al., 2015)

Rab8¹/Rab8^B229 has abnormal neuroanatomy | third instar larval stage phenotype, suppressible by tkv^k16713/tkv[+]

(West et al., 2015)

Rab8¹/Rab8^B229 has abnormal neuroanatomy | third instar larval stage phenotype, suppressible by tkv^k16713/tkv⁷

(West et al., 2015)

Rab8¹/Rab8^B229 has abnormal neuroanatomy | third instar larval stage phenotype, suppressible by Scer\GAL4^RapGAP1-OK6/kay^Fbz.UAS

(West et al., 2015)

Rab8¹/Rab8^B229 has abnormal neuroanatomy | third instar larval stage phenotype, suppressible by Scer\GAL4^nSyb.PS/kay^Fbz.UAS

(West et al., 2015)

Rab8¹/Rab8^B229 has abnormal neuroanatomy | third instar larval stage phenotype, suppressible by POSH^EP1206

(West et al., 2015)

Rab8¹/Rab8^B229 has abnormal neuroanatomy | third instar larval stage phenotype, suppressible by POSH^EP2248

(West et al., 2015)

Rab8¹/Rab8^B229 has abnormal neuroanatomy | third instar larval stage phenotype, suppressible by Tak1[+]/Tak1¹⁷⁹

(West et al., 2015)

Rab8¹/Rab8^B229 has abnormal neuroanatomy | third instar larval stage phenotype, suppressible by Tak1^RNAi.UAS.cUa/Scer\GAL4^nSyb.PS

(West et al., 2015)

Rab8¹/Rab8^B229 has abnormal neuroanatomy | third instar larval stage phenotype, suppressible by Tak1^K46R.M.UAS/Scer\GAL4^nSyb.PS

(West et al., 2015)

Enhancer of

Statement

Reference

Rab8¹ is an enhancer of visible phenotype of Hsap\CHMP2B^Intron5.UAS, Scer\GAL4^GMR.PF

(West et al., 2015)

Other

Statement

Reference

Hrs^D28, Rab8¹/Rab8[+] has abnormal neuroanatomy phenotype

(West et al., 2015)

Rab8¹/Rab8[+], puc^E69 has abnormal neuroanatomy phenotype

(West et al., 2015)

Dad^ΔIEL, Rab8¹/Rab8[+] has abnormal neuroanatomy phenotype

(West et al., 2015)

Phenotype Manifest In

Suppressed by

Statement

Reference

Rab8¹/Rab8^B229 has embryonic/larval neuromuscular junction | third instar larval stage phenotype, suppressible by Hrs^UAS.cUa/Scer\GAL4^nSyb.PS

(West et al., 2015)

Rab8¹/Rab8^B229 has NMJ bouton | third instar larval stage phenotype, suppressible by tkv⁷/tkv[+]

(West et al., 2015)

Rab8¹/Rab8^B229 has embryonic/larval neuromuscular junction | third instar larval stage phenotype, suppressible by POSH^EP1206

(West et al., 2015)

Rab8¹/Rab8^B229 has NMJ bouton | third instar larval stage phenotype, suppressible by POSH^EP1206

(West et al., 2015)

Rab8¹/Rab8^B229 has embryonic/larval neuromuscular junction | third instar larval stage phenotype, suppressible by POSH^EP2248

(West et al., 2015)

Rab8¹/Rab8^B229 has NMJ bouton | third instar larval stage phenotype, suppressible by POSH^EP2248

(West et al., 2015)

Rab8¹/Rab8^B229 has embryonic/larval neuromuscular junction | third instar larval stage phenotype, suppressible by Tak1[+]/Tak1¹⁷⁹

(West et al., 2015)

Rab8¹/Rab8^B229 has NMJ bouton | third instar larval stage phenotype, suppressible by Tak1[+]/Tak1¹⁷⁹

(West et al., 2015)

Rab8¹/Rab8^B229 has embryonic/larval neuromuscular junction | third instar larval stage phenotype, suppressible by Tak1^RNAi.UAS.cUa/Scer\GAL4^nSyb.PS

(West et al., 2015)

Rab8¹/Rab8^B229 has NMJ bouton | third instar larval stage phenotype, suppressible by Tak1^RNAi.UAS.cUa/Scer\GAL4^nSyb.PS

(West et al., 2015)

Rab8¹/Rab8^B229 has embryonic/larval neuromuscular junction | third instar larval stage phenotype, suppressible by Tak1^K46R.M.UAS/Scer\GAL4^nSyb.PS

(West et al., 2015)

Rab8¹/Rab8^B229 has NMJ bouton | third instar larval stage phenotype, suppressible by Tak1^K46R.M.UAS/Scer\GAL4^nSyb.PS

(West et al., 2015)

Rab8¹/Rab8^B229 has embryonic/larval neuromuscular junction | third instar larval stage phenotype, suppressible by tkv^k16713/tkv[+]

(West et al., 2015)

Rab8¹/Rab8^B229 has NMJ bouton | third instar larval stage phenotype, suppressible by Hrs^UAS.cUa/Scer\GAL4^nSyb.PS

(West et al., 2015)

Rab8¹/Rab8^B229 has NMJ bouton | third instar larval stage phenotype, suppressible by tkv^k16713/tkv[+]

(West et al., 2015)

Rab8¹/Rab8^B229 has embryonic/larval neuromuscular junction | third instar larval stage phenotype, suppressible by tkv^k16713/tkv⁷

(West et al., 2015)

Rab8¹/Rab8^B229 has NMJ bouton | third instar larval stage phenotype, suppressible by tkv^k16713/tkv⁷

(West et al., 2015)

Rab8¹/Rab8^B229 has embryonic/larval neuromuscular junction | third instar larval stage phenotype, suppressible by Scer\GAL4^RapGAP1-OK6/kay^Fbz.UAS

(West et al., 2015)

Rab8¹/Rab8^B229 has NMJ bouton | third instar larval stage phenotype, suppressible by Scer\GAL4^RapGAP1-OK6/kay^Fbz.UAS

(West et al., 2015)

Rab8¹/Rab8^B229 has embryonic/larval neuromuscular junction | third instar larval stage phenotype, suppressible by Scer\GAL4^nSyb.PS/kay^Fbz.UAS

(West et al., 2015)

Rab8¹/Rab8^B229 has NMJ bouton | third instar larval stage phenotype, suppressible by Scer\GAL4^nSyb.PS/kay^Fbz.UAS

(West et al., 2015)

Enhancer of

Statement

Reference

Rab8¹ is an enhancer of axoneme | spermatogenesis phenotype of Fam92^c.4-789Del

(Wu et al., 2020)

Rab8¹ is an enhancer of axoneme | spermatogenesis phenotype of Cby^c.121delC

(Wu et al., 2020)

Rab8¹ is an enhancer of eye phenotype of Hsap\CHMP2B^Intron5.UAS, Scer\GAL4^GMR.PF

(West et al., 2015)

Other

Statement

Reference

Hrs^D28, Rab8¹/Rab8[+] has NMJ bouton | third instar larval stage phenotype

(West et al., 2015)

Hrs^D28, Rab8¹/Rab8[+] has embryonic/larval neuromuscular junction | third instar larval stage phenotype

(West et al., 2015)

Rab8¹/Rab8[+], puc^E69 has NMJ bouton | third instar larval stage phenotype

(West et al., 2015)

Rab8¹/Rab8[+], puc^E69 has embryonic/larval neuromuscular junction | third instar larval stage phenotype

(West et al., 2015)

Dad^ΔIEL, Rab8¹/Rab8[+] has NMJ bouton | third instar larval stage phenotype

(West et al., 2015)

Dad^ΔIEL, Rab8¹/Rab8[+] has embryonic/larval neuromuscular junction | third instar larval stage phenotype

(West et al., 2015)

Additional Comments

Genetic Interactions

Statement

Reference

When present in the genetic background, heterozygous tkv⁷ reduces the synaptic overgrowth in Rab8¹/Rab8^B229 mutants.

When present in the genetic background, heterozygous tkv^k16713 reduces the synaptic overgrowth in Rab8¹/Rab8^B229 mutants.

When present in the genetic background, trans-heterozygous tkv⁷/tkv^k16713 reduces the synaptic overgrowth in Rab8¹/Rab8^B229 mutants.

Although heterozygous Rab8¹ or Dad^ΔIEL mutants alone do not show any perturbation to synaptic bouton number, their heterozygous combination engenders an increased bouton number compared to wild-type.

Neuronal expression of kay^Fbz.Scer\UAS under the control of Scer\GAL4^RapGAP1-OK6 is sufficient to completely alleviate the synaptic overgrowth in Rab8¹/Rab8^B229 mutants.

Neuronal expression of kay^Fbz.Scer\UAS under the control of Scer\GAL4^nSyb.PS is sufficient to completely alleviate the synaptic overgrowth in Rab8¹/Rab8^B229 mutants.

Heterozygous combinations of puc^E69 and Rab8¹ results in an increase in synaptic bouton number compared with wild-type.

Introducing POSH^EP1206 into a Rab8¹/Rab8^B229 mutant background alleviates the synaptic overgrowth phenotype.

Introducing POSH^EP2248 into a Rab8¹/Rab8^B229 mutant background alleviates the synaptic overgrowth phenotype.

(West et al., 2015)

Xenogenetic Interactions

Statement

Reference

Complementation and Rescue Data

Partially rescued by

Rab8¹/Rab8^B229 is partially rescued by Scer\GAL4^Act5C.PI/Rab8^UAS.cWa

(West et al., 2015)

Rab8¹/Rab8^B229 is partially rescued by Scer\GAL4^nSyb.PS/Rab8^UAS.cWa

(West et al., 2015)

Rab8¹/Rab8^B229 is partially rescued by Scer\GAL4^Mhc.PW/Rab8^UAS.cWa

(West et al., 2015)

Comments

Expression of Rab8^Scer\UAS.cWa under the control of Scer\GAL4^Act5C.PI and the presynaptic driver Scer\GAL4^nSyb.PS is sufficient to completely rescue the increased bouton number at muscles 6/7 Rab8¹/Rab8¹ mutants.

Synaptic bouton number or length in muscle 4 is not rescued by muscle expression of Rab8^Scer\UAS.cWa.

(West et al., 2015)

Images (0)

Mutant

Wild-type

Stocks (1)

Bloomington

26173

Rab8¹ red¹ e⁴/TM6B, Sb¹ Tb¹ ca¹

Notes on Origin

Discoverer

J. Kennison

(Zhu et al., 2005)

Isolated in a screen for lethal mutations that fail to complement Df(3L)kto2.

(Zhu et al., 2005)

External Crossreferences and Linkouts ( 0 )

Synonyms and Secondary IDs (3)

Reported As

Symbol Synonym

Rab8¹

(Chang et al., 2024, Ochi et al., 2022, Kohrs et al., 2021, Devergne et al., 2017, West et al., 2015, Cook, 2008.12.1)

l(3)76BDu¹

rab8¹

(Wu et al., 2020, Giagtzoglou et al., 2012)

Name Synonyms

Secondary FlyBase IDs

FBal0219685
FBal0190659

References (12)

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