Worm Breeder's Gazette 11(5): 43
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.
We have been screening expression libraries for clones encoding potential myogenic regulatory factors. Oligonucleotides covering the unc-54 enhancer and promoter segments (see WBG 11#2 p. 23) were catenated and radioactively labelled. These were then used to screen plaques from a variety of genomic and cDNA expression libraries (from Clonetech, Stratagene and Bob Barstead). Positive plaques were followed by confirming binding to the specific oligonucleotides, and by testing for binding to nonspecific oligos. The only clones to date which exhibit strong specificity for myosin control sequences are four phage from a Clonetech lambda gt11 cDNA library. The fusion proteins produced by these clones bind to both the internal and upstream control regions from unc-54, but do not bind to two other non-specific double stranded oligonucleotides or to single stranded DNA. Three of the phage have inserts of about 5 kb and one has an insert of 1.4kb. The four clones are identical in the region just 3' to lacZ in lambda gt11. All four phage produce -gal fusion proteins with identical gel mobilities, each containing 32kd of protein encoded by the insert. The fusion proteins are unstable in E. coli.The 1.4kb insert has been sequenced and encodes a zinc finger protein, which belongs to the same class as the Drosophila Kruppel gene product.