Worm Breeder's Gazette 11(5): 30

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.

sdc-1 Encodes a Zinc Finger Protein

Michael L. Nonet and Barbara J. Meyer

Figure 1

The X-linked sdc-1 gene is required for the hermaphrodite mode of 
sex determination and dosage compensation, acting at a point before 
the divergence of the two pathways.  We have previously described (WBG 
11(3):28) both the localization of the sdc-1 gene to a 10 kb interval 
of the cosmid R09G6 and the identification of a single 3.8 kb 
transcript from the region.  This transcript is found at some level in 
all developmental stages, but is at least 10-fold more abundant in 
eggs than in any other stage.
We have isolated three independent partial cDNA clones of the 3.8 kb 
transcript (2.2 kb, 2.8 kb and 3.6 kb) from Stewart Kim's mixed-stage 
library.  [Four additional clones that contained double ligation 
events were also partially characterized.]  We have sequenced the 
largest cDNA, genomic DNA upstream of 5' end of the cDNA, and selected 
other genomic regions.  From this examination we believe the sdc-1 
transcript is 3.75 kb in length (not counting the poly A tail) and 
contains at least 9 exons.  sdc-1 encodes a 1203 amino acid protein 
containing seven TFIIIA-like zinc fingers (A) located in singlets and 
doublets scattered throughout the first two-thirds of the gene (B).  
sdc-1 does not appear to contain domains with homology to known 
transcriptional activating motifs.
One additional note: Although we are capable of detecting an SL1 
trans-spliced version of the sdc-1 transcript using PCR, primer 
extension experiments demonstrate that at least 90% of sdc-1 RNA found 
in embryos extends at least 50 bp upstream of the SL1 trans-splicing 
[See Figure 1]

Figure 1