Worm Breeder's Gazette 14(2): 79 (February 1, 1996)

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.

emb-8 mislocalizes Glp-1 and P-granules

M. L. A. Khan, Shahid. S. Siddiqui

Lab. of Molecular Biology. Toyohashi University of Technology, Toyohashi 441, Japan.

We have previously reported the transformation rescue of the 
emb-8(hc69) mutant with a cosmid containing the gene cej-1(C.
elegans Meeting 1995, abstract 310). emb-8 is   an embryonic
lethal mutant at nonpermissive temperature (25oC). Cell division 
arrest between one cell to 50 cells stage. The egg shell is 
osmotically sensitive. Recently we have come to know from Sarah
Crittenden( Judith Kimble Lab.) that emb-8 mislocalizes Glp-1 & 
P-granules specific antigens. We have earlier observed symmetric
distribution of P-granules in a fraction of embryos using a
monoclonal antibody specific to germ cells. These observation
suggest a role of emb-8 in early cell divisions of the embryos.

We have narrowed down the rescueing length of the DNA. It is 
about 5.5 kb which contain about 2.5 kb coding sequence and
arround 3 kb noncoding upstream sequence. The rescuing ability
of the 5.5 kb genomic DNA fragment appears less than when the 
whole cosmid ZC235 is used in the transformation experiment.This
5.5 kb fragment contains a single gene which we named as cej-1.
This gene encodes a novel protein of 600 a.a. which have no 
significant homology with any protein in the data bank. It shows
about 30% identity  with calphotin,      spasmolysin precursor, 
Hypothetical Protein 2280, in a stretch of about 200 a.a. & about
similar identity with Endochitinase, Glucan 1,4-alpha-Glucosidase,
GVPC protein, Hydroxy proline-rich glycoprotein precursor, mRNA
cap binding protein, Probable cell surface glycoprotein sed1, in a
stretch of about 100 a.a. The CEJ-1 protein   has three   70 a.a. 
repeats,six 30 a.a.repeats &  three 20 a.a.   repeats. Northern  
analysis suggest that the cej-1 expresses in L3 larvae, gradually
increasing as the development proceeds reaching a maximum in adult
animals. Signal is detected only in the early as we did not observe
any signal after 1.5 hours of the first cleavage. We are further
performing in situ and immunocytochemical studies on emb-8 embryos.
We thank Sarah Crittenden for  her unpublished results,and 
Glp-1 antibody; Kikuno for the analysis of       the cej-1 protein
structure; Yuji Kohara for cDNA clones; Alan Coulson for cosmid 
DNA; J. Miwa for advice and encouragement.