Worm Breeder's Gazette 14(3): 54 (June 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.


Dave Pilgrim1, Lee Venolia2

1 Department of Biological Sciences, University of Alberta, Edmonton, Canada
2 Department of Biology, Williams College, Williamstown, MA

      Several years ago, we described rescue of unc-45 with a cosmid (WBG
11#5 p23). Since that time we have been badgering away trying to narrow
down the gene. The minimal rescuing region of F30H5 turns out to be about
14 kbp, and this was used to pull some incomplete cDNA clones. Thanks to
the Genome Sequencing project, which went through this region fairly early
in their mandate, we did not have to do much more sequencing. There turned
out to be a single ORF in the region consisting of 11 exons, and between
the cDNA clones, RACE and PCR sequencing across putative exon boundaries,
the GENEFINDER predictions were (mostly) confirmed. We cloned the C.
briggsae homologue by low-stringency hybridization, and although genomic
sequencing of the C.b.unc-45 is not complete, the two proteins are very
similar (not surprising) and it looks like intron 7 is missing in the C.
briggsae clone (e.g. exons 7 and 8 are contiguous in the genome). As we
have seen with unc-119, the C. briggsae gene may be more compact than the
C. elegans homologue due to smaller introns.

      UNC-45 is predicted to have 961 amino acids, and is not directly
homologous to any sequences in the databases. However, a region of 120
amino acids at the amino terminus (and scattered residues throughout)
shows significant similarity to a several proteins (yeast to humans) which
are serine/threonine protein phosphatases, suggesting a regulatory role
for UNC-45 in early muscle cell development. We are in the midst of all
the obvious expression studies, but no results yet.