THE TPA-1 GENE OF CAENORHABDITIS ELEGANS ENCODES TWO PROTEINS SIMILAR TO CA2+-INDEPENDENT PROTEIN KINASE CS - EVIDENCE BY COMPLETE GENOMIC AND COMPLEMENTARY DNA SEQUENCES OF THE TPA-1 GENE

摘要

The gene tpa-1 on chromosome IV of the nematode Caenorhabditis elegans plays a major and definitive role in the adversary action of tumour-promoting phorbol esters, which induce growth arrest and locomotory distress in the animal. The gene was deduced to code for a protein kinase C (PKC) homologue by molecular cloning. We have now sequenced the complete genomic and complementary DNAs for tpa-1 and have analysed their structural features in detail: (1) tpa-1 spans over 20 kb consisting of eleven exons and ten introns; (2) two different-sized mRNAs are generated from the tpa-1 locus; (3) both mRNAs are trans-spliced to the trans-spliced leader SL1; (4) both mRNAs encode PKC isoforms, which are most similar to Ca2+-independent novel PKC theta; (5) the two PKC isoforms differ from each other in that the smaller lacks the amino-terminal region of the larger corresponding to the first four exons and a portion of the fifth exon; and (6) three introns are located at; identical positions in the polypeptide sequences aligned between the C. elegans tpa-1 product and a PKC of the fruit fly Drosophila melanogaster. [References: 54]