emigh@ecsvax.UUCP (Ted Emigh) (04/14/87)
A recent Nature (Vol 326, 5 March 1987, pp 42-47) has the following article: "A family of unusually spliced biologically active transcripts encoded by a Drosophila clock gene," by Yoav Citri, et. al. (Brandeis Univ). Abstract: "Complementary DNA cloning of the transcripts of the Drosophila clock gene period reveals three distinct transcripts. These result from unusual splicing pathways, one involving a CG 3' splice site and one resulting in the use of two different reading frames in one exon, and they predict three separate proteins. Two of the cloned cDNAs can restore clock function to mutant arrhythmic flies." This appears to be the best evidence to date of multiple reading frames in eukaryotes. Notice that they have not located the proteins yet. To my mind, this may have arisen for somewhat of the same reason as DNA splicing in the immunoglobulins. The exon for the alternate reading frame is about 4800 bp in length. -- Ted H. Emigh Genetics and Statistics, North Carolina State U, Raleigh NC USENET: mcnc!ecsvax!emigh DOMAIN: emigh%ecsvax.ncecs.edu ARPA: ecsvax!emigh@mcnc.org BITNET: NEMIGH@TUCC
werner@aecom.UUCP (Craig Werner) (04/16/87)
In article <2909@ecsvax.UUCP>, emigh@ecsvax.UUCP (Ted Emigh) writes: > A recent Nature (Vol 326, 5 March 1987, pp 42-47) has the following article: > > "A family of unusually spliced biologically active transcripts encoded > by a Drosophila clock gene," by Yoav Citri, et. al. (Brandeis Univ). > > Abstract: > "Complementary DNA cloning of the transcripts of the Drosophila clock gene > period reveals three distinct transcripts. These result from unusual splicing > pathways, one involving a CG 3' splice site and one resulting in the use of > two different reading frames in one exon, and they predict three separate > proteins. Two of the cloned cDNAs can restore clock function to mutant > arrhythmic flies." Again, just like Polyoma, the above is cheating, since the other exons are in identical reading frames. Besides, only two reading frames are used even in the parts where they diverge. Alternate splicing should not be confused with transcripts in all three reading frames. Let's just drop the subject. It is clear that the only real answer to the question of "How much information does the human genome encode (in its 3 * 10^9 bp)?" is LOTS and LOTS. Perhaps we should dub the quantity One Sagan. -- Craig Werner (MD/PhD '91) !philabs!aecom!werner (1935-14E Eastchester Rd., Bronx NY 10461, 212-931-2517) "But I digress..."