We are interested in the control of cell cycle in C. elegans and wish to use genetics to describe the various genes and their parts in the regulation of cell division. We started with
cm4 g2 ,a
cdc2 cDNA homolog from C. Martin, B. Waterston, J. Sulston et al.. We determined the complete cDNA sequence of the gene from this clone and a homologous clone selected from B. Barstead cDNA library: the protein is 72% identical (89% homologous) to human
cdc2 .We mapped it on center II (Y24H1 ),then narrowed its position to about 20 kb on the physical map (thanks to Alan Coulson et al.). Connection to the genetic map was achieved by testing the presence of our gene in four deficiencies of the area, generated by B. Herman and provided by M. Edgley. We used PCR on single embryos, a marvellous technique developed by Barstead, Schrankc and Waterston, which in our hands works routinely on 80-cell embryos. Our
cdc2 gene appears to be present in these four deficiencies, so it lies in a region that includes three known genes: a maternal effect lethal
zyg-9 which affects the first embryonic mitosis, a zygotic lethal let 252 and a haplo-insufficient locus.
zyg-9 looked like a good candidate from its phenotype. In addition four putative polymorphic alleles have been recovered, three mutator-induced by Phil Carter and Bob Edgar, one psoralen induced by Julie Ahringer. Using PCR we showed however that none of the four is structurally rearranged in the transcribed
cdc2 region. We are now analyzing the alleles by genomic Southern, and trying to rescue the three known functions in the area by transformation with the cosmids. We are also interested in other
cdc2 -1ikegenes -another atypical PSTAVRE (like
cm4 g2 )containing gene has been studied in Paul Sternberg's- but is there a "true" PSTAIRE containing gene? What are the functions, inter-relations, specificities or redundancies of this set of genes ?