SUP-17, a Caenorhabditis elegans ADAM protein related to Drosophila KUZBANIAN, and its role in LIN-12/NOTCH signalling.

LIN-12/NOTCH proteins mediate cell-cell interactions that specify cell fates. Previous work suggested that sup-17 facilitates lin-12 signalling in Caenorhabditis elegans. Here, we show that sup-17 encodes a member of the ADAM family of metalloproteases. SUP-17 is highly similar to Drosophila KUZBANIAN, which functions in Drosophila neurogenesis, and the vertebrate ADAM10 protein. Furthermore, we show by genetic analysis that the extracellular domain of LIN-12 appears to be necessary for sup-17 to facilitate lin-12 signalling and that sup-17 does not act downstream of lin-12. Finally, we show by cell ablation experiments that sup-17 can act cell autonomously to facilitate lin-12 activity. We discuss the implications of our observations for LIN-12/NOTCH signalling and how our results complement and extend results obtained from genetic analysis of kuz in Drosophila.