Worm Breeder's Gazette 11(1): 44
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.
[See Figure 1] Bold sequence is contiguous in the genome (lower case=intron). The open characters show sequence, which, although at the 5' end of the message, does not occur within at least 3 kb upstream of ama-1.The absence of splice signals suggest that this 29 bp sequence is not an ama-1 exon. Our initial assumption was that this short extension was a cloning artifact. However, a data base search revealed that these 29 bp are identical with residues 951-980 of dpy-13, and encode a helix to non- helix transition near the carboxyl terminus of this collagen. Since ama-1 and dpy-13 are very close on LGIV (dpy-13 is 11 kb 5' from ama-1) , we speculate that the ligation of a stretch of RNA from the abundantly expressed dpy-13 to the ama-1 transcript occured in vivo, although we hesitate to propose a mechanism. Currently we are using primer extension and PCR approaches to assess how common this event might be.