Alternatively Spliced mRNAs for Human Endothelin-2 and Their Tissue Distribution

The cDNA for Endothelin-2 (ET-2) has been previously cloned and characterised; however, ET-2 remains the least studied of the endothelin isopeptides and little is known of its function and location. In the present study reverse transcriptase-polymerase chain reaction revealed the presence of seven alternatively spliced mRNA variants encoding ET-2, with a specific pattern of distribution in various human tissues. Computer alignment and analysis of the DNA sequences demonstrated alternative splicing of five exons of 52, 169, 123, 99 and 174 base pairs, in the carboxy terminal region of the mRNA encoding preproET-2. This region contains sites for the post-transcriptional processing of preproET-2 into mature ET-2, therefore we postulate that post-transcriptional processing may be disrupted or altered in these variants.