sel-9 mutations were first isolated in a screen for suppressors of
lin-12(
n676n930), a
lin-12 hypomorphic mutation(1). Recently, in a complementation screen for new
sel-9 mutations, we have obtained more alleles of
sel-9 which show strong interactions with both
lin-12 and
glp-1 mutations. One class of
sel-9 mutations, probably gain-of-function alleles, increase
lin-12 and
glp-1activity. The other class of mutation, represented by a probable loss-of-function allele, decreases
lin-12 and
glp-1activity. From genetic analysis, we propose that
sel-9 defines a postive regulator or effector in the
lin-12 and/or
glp-1 pathways. Some of the
sel-9 alleles also show new phenotypes in a wild type background, suggesting additional roles for
sel-9 other than the involvement in the
lin-12 and
glp-1 pathways. We have also been trying to clone the
sel-9 gene.
sel-9 maps to LG V, between the left hand break points of two deficiencies, sDf47 and mDf3, a region covered by a few cosmids and YACs. Preliminary experiments indicate that
sel-9 can be rescued by a single cosmid clone. We are trying to verify this result with the new
sel-9 alleles. 1) Sundaram, M. and I. Greenwald 1993 Suppressors of a
lin-12 hypomorph define genes that interact with both
lin-12 and
glp-1 in Caenorhabditis elegans. Genetics 135: 765-783.