Worm Breeder's Gazette 9(1): 16

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.

Identification and Isolation of the Coding Regions Around unc-22

S. Prasad and D.L. Baillie

Our laboratory has been intensively studying the region around unc-
22 gene over the last eight years using conventional genetic analysis. 
We have obtained cosmids from John Sulston that cover approximately 
500 kb.  of DNA.  These cosmids were identified by means of Tcl RFLD 
flanking sequences (isolated by Karen Beckenbach) in the region which 
lies immediately to the left and right of unc-22 gene.
We are currently examining the region flanked by dpy-20 on the left 
and unc-22 on the right.  Five overlapping cosmids have been 
identified which cover this region, (these include D.  Moerman's and R.
Waterston's unc-22 clones).  We are using the method suggested by T. 
Snutch to identify putative coding regions (Divergent regions between 
C.  elegans and C.  briggsae include mostly non-coding DNA sequences 
whereas the highly conserved regions are likely to code for the 
proteins essential for nematode growth, development and reproduction). 
We have restriction mapped and subcloned Hind III and Pst I fragments 
from these cosmids into pUC19.  Nick translated individual fragments 
have been used to probe Bristol and C.  briggsae DNA.  This technique 
helps us to identify the conserved regions or the coding sequences in 
C.  briggsae DNA.
We are now in the process of screening B.  Meyers's lambda gt10 cDNA 
library with the probes which show homology to the C.  briggsae DNA.  
We intend to identify and isolate the major coding regions that lie 
between unc-22 and dpy-20 regions using this approach.  The isolation 
of cDNA clones will be used to study gene expression and regulation 
during nematode development.  The isolated cDNA clones will be 
sequenced in order to identify the nature of protein coded for by 
particular gene(s) in this region.