(A/T)GATA(A/G) motifs have been previously noted upstream of a number of cuticular collagen genes in C.elegans (Cox et al 1989) and we have recently implicted such a motif in the regulation of
dpy-7 by deletion analysis of reporter gene constructs (Gilleard, Barry and Johnstone, this issue). Since none of the currently identified C.elegans GATA factors have been shown to be expressed in the post-embryonic hypodermis (
elt-1,
elt-2 and
end-1) I decided to look for new GATA factors using PCR with degenerate primers. Nested primers across the Zinc finger domain used in conjunction with an SL1 oligo identified a new family member which I have called
elt-3. One full length cDNA (cloned from Bob Barstead's mixed stage library) is 1253bp in length (SL1 trans spliced) and encodes a polypeptide of 226aa with a 490bp 3' UTR. A second cloned cDNA of 1003bp (has a truncated 3' end which I suspect is an artefact of oligo dT mispriming) has SQG in place of a C near the N terminus due to an alternative splicing event at the 5' end of the second exon. Further cDNAs are being examined to determine the relative abundance of the alternative transcripts and determine whether any other forms exist. The predicted polypeptide has a single GATA zinc finger (C-X2-C-X17-C-X2-C) which is homologous to the C.terminal finger of "2 finger" GATA factors.