Abstract
The organization and expression of the Drosophila melanogaster G-protein gamma subunit-encoding gene (D-G gamma 1) were analyzed. The results showed that the three D-G gamma 1 RNAs (1.1, 1.3 and 2.6 kb) are differentially expressed in different tissues. While the 2.6-kb RNA is found only in the neural tissues of late embryo, larva and adult, the 1.3-kb RNA is expressed only in the adult ovary. The 1.1-kb RNA, on the other hand, is predominantly expressed during embryogenesis and in the neural tissues of late embryo, larva and adult. Moderate expression of this RNA is also found in the imaginal discs and other larval tissues. Nucleotide (nt) sequence analysis showed that the 70-amino-acid polypeptide encoded by the 1.3-kb transcript of D-G gamma 1 is the same as that encoded by the 1.1- and 2.6-kb D-G gamma 1 transcripts reported earlier [Ray and Ganguly, J. Biol. Chem. 267 (1992) 6086-6092]. Both the 1.3- and 1.1-kb RNAs utilize the same polyadenylation site, but their 3'-UTR are 1662 nt shorter than that of the 2.6-kb RNA. Although transcription of all three RNAs starts at the same transcription start point (tsp), the 5'-UTR of the 1.3-kb RNA is 190-nt longer than that of the other two RNAs, due to the utilization of an 3' alternative splice site.(ABSTRACT TRUNCATED AT 250 WORDS)
