Vulval cells

Ferguson, E.L. and Horvitz, H.R. (1985). Identification and characterization of 22 genes that affect the vulval cell lineages of the nematode Caenorhabditis elegans. Genetics 770 17-72. 

In both worm and fly, the Ras protein acts as a switch that determine cell fate. In C. elegans, the activation of Ras determines the formation of vulval as opposed to hypodermal (skin) cells (for sequence of events, see Table 8.4). In Drosophila photoreceptors, the activation of Ras determines the development of R7 as a neuronal as opposed to a cone cell. In both cases, Ras proteins operate downstream of receptor tyrosine kinases that are activated by cell-cell interactions. 

A mbros Less is known about how cki-1 is shut off in VPCs than about how cki-1 is turned on in these cells. However, when we misexpress lin-14 late in development, it will maintain cki-1 expression later than in the normal vulval lineage. Therefore, extinction of cki-1 expression in VPCs is influenced by some activity that is in turn dependent on lin-14 down-regulation. All our cki-1 expression constructs retain the 3hUTR of cki-1 (Hong et al 1998), and so the dynamic cki-1 expression we observe could reflect post-transcriptional regulation in addition to transcription regulation. 

Yoon, C. H., C. Chang, N. A. Hopper, G. M. Lesa, and P. W. Sternberg. Requirements of multiple domains of SLI-I, a Caenorhabditis elegans homologue of c-Cbl, and an inhibitory tyrosine in LET-23 in regulating vulval differentiation. Mol Biol Cell. 11 4019-31.2000. 

Kaech SM, Whitfield CW, Kim SK. The LIN-2/LIN-7/LIN-10 complex mediates basolateral membrane localization of the C. elegans EGF receptor LET-23 in vulval epithelial cells. Cell 1998 94 761-771. 

Clandinin, T.R., Katz, W.S., Sternberg, P.W. 1997. Caenorhabditis elegans HOM-C genes regulate the response of vulval precursor cells to inductive signal. Dev. Biol. 182, 150-161. 

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