Genetic modifiers of the Drosophila NSF mutant, comatose, include a temperature-sensitive paralytic allele of the calcium channel alpha 1-subunit gene, cacophony
B. Dellinger et al., Genetic modifiers of the Drosophila NSF mutant, comatose, include a temperature-sensitive paralytic allele of the calcium channel alpha 1-subunit gene, cacophony, GENETICS, 155(1), 2000, pp. 203-211
The N-ethylmaleimide-sensitive fusion protein (NSF) has been implicated in
vesicle trafficking in perhaps all eukaryotic cells. The Drosophila comatos
e (comt) gene encodes an NSF homolog, dNSF1. Our previous work with tempera
ture-sensitive (TS) paralytic alleles of comt has revealed a function for d
NSF1 at synapses, where it appears to prime synaptic vesicles for neurotran
smitter release. To further examine the molecular basis of dNSF1 function a
nd to broaden our analysis of synaptic transmission to other gene products,
we have performed a genetic screen for mutations that interact with comt.
Here we report the isolation and analysis of four mutations that modify TS
paralysis in comt, including two intragenic modifiers tone enhancer and one
suppressor) and two extragenic modifiers (both enhancers). The intragenic
mutations will contribute to structure-function analysis of dNSF1 and the e
xtragenic mutations identify gene products with related functions in synapt
ic transmission. Both extragenic enhancers result in TS behavioral phenotyp
es when separated from comt, and both map to loci not previously identified
in screens for TS mutants. One of these mutations is a TS paralytic allele
of the calcium channel alpha 1-subunit gene, cacophony (cac). Analysis of
synaptic function in these mutants alone and in combination will further de
fine the in vivo functions and interactions of specific gene products in sy
naptic transmission.