Worm Breeder's Gazette 11(1): 33

These abstracts should not be cited in bibliographies. Material contained herein should be treated as personal communication and should be cited as such only with the consent of the author.

A Presumed Gene for G Protein alpha Subunit of C. elegans

S. Ohshima, S. Tashiro, J.-H. Park, T. Tani and Y. Ohshima

Figure 1

As an approach to analyze neuronal signal transduction in C.  
elegans, we attempted to characterize a gene for guanine nucleotide-
binding regulatory protein (G protein).  Rat cDNA probes for Gsalpha 
and Goalpha, described by Itoh et al., Proc.  Natl.  Acad.  Sci.  USA. 
83, 3776-3780 (1986), revealed a few bands on a Southern blot of C.  
elegans N2 total DNA digested with HindIII, EcoRI or XbaI.  A single 
clone was isolated from N2 genomic library in lambdaEMBL-4 from Dr.  C.
Link, and another from a library in lambda2001 from Dr.  A.  Coulson,
by screening with the 1.1kb EcoRI fragment corresponding to the C-
terminal 2/3 of rat Gsalpha (pGI11L).  The two clones are similar and 
probably overlapping.  The former clone (lambdaEGLI-9) produces 
hybridizing fragments on a Southern blot comparable to those from 
total DNA, and it was further characterized.  A 0.8kb XbaI fragment, 
which hybridizes strongly with the 11L probe, was sequenced.  It 
carries a sequence potentially coding for 48 amino acid sequence which 
is highly homologous to that found at the C-terminus of the rat 
Gsalpha (see below).  Fourty-four amino acids out of 48 are identical 
between the two sequences.  The sequence 5' to this region and within 
the XbaI fragment does not show significant homology with the probe, 
and seems to be an intron.  Another fragment, which hybridizes to the 
rat Gsalpha cDNA fragment corresponding to the N-terminal 1/3 (pGI11S),
resides 5' to the sequenced XbaI fragment.  Therefore, this clone may 
carry the entire gene coding for a Gsalpha subunit.  We are further 
analyzing this clone, and also trying to clone a corresponding cDNA 
from the library of Dr.  B.  Barstead.  Screening the lambda2001 
genomic library with the N-terminal cDNA probe produced seven positive 
clones.  A few of these were partially sequenced, but none revealed a 
putative coding region for Gsalpha.  Synthetic oligonucleotide probes 
for the conserved GTPase or guanine-binding regions revealed several 
bands on a Southern blot of C.  elegans total DNA.  We are also 
screening genomic clones with these oligonucleotide probes.
[See Figure 1]

Figure 1