Alternative splicing of transcripts expressed by the Manduca sexta allatotropin (Mas-AT) gene is regulated in a...

The Manduca allatotropin (Mas-AT) gene is expressed as at least three mRNA isoforms that differ from each other by alternative splicing. The location at which the alternative exons are included in the mature mRNAs occur within the open reading frame, so that three different propeptides are predicted as translation products. In the pharate adult insect, the major mRNA isoform expressed in the brain and frontal ganglion differs from that expressed in the nerve cord. Examination of the deduced translations of the alternative exons reveals the presence of three additional Mas-AT-like sequences that are flanked by basic amino acid residues. Therefore, the Mas-AT-like sequences present within the gene may be derived from a duplication of an ancestral Mas-AT-like sequence followed by divergence.