The molecular evolution of the allatostatin precursor in cockroaches

• Published in: Peptides (New York, N.Y. : 1980) Vol. 20; no. 1; pp. 11 - 22
• Main Authors: Bellés, Xavier, Graham, Laurie A., Bendenab, William G., Ding, Qi, Edwards, John P., Weaver, Robert J., Tobe, Stephen S.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.01.1999
• Subjects: Allatostatin; Amino Acid Sequence; Animals; Base Sequence; Blaberus craniifer; Blatta orientalis; Blattella germanica; Cockroach; Cockroaches - genetics; Evolution, Molecular; Molecular Sequence Data; Neuropeptide; Neuropeptides - classification; Neuropeptides - genetics; Peptide evolution; Phylogeny; Sequence Homology, Amino Acid; Sequence Homology, Nucleic Acid; Supella longipalpa; Cockroach; Phylogeny; Neuropeptide; Allatostatin; Peptide evolution
• ISSN: 0196-9781; 1873-5169
• DOI: 10.1016/S0196-9781(98)00155-7

Allatostatins (ASTs) of the Tyr/Phe-Xaa-Phe-Gly Leu/Ile-NH2 family are a group of insect neuropeptides that inhibit juvenile hormone biosynthesis by the corpora allata. We have obtained genomic DNA sequences that specify the preproallatostatin precursor for the cockroaches, Blatta orientalis, Blattella germanica, Blaberus craniifer and Supella longipalpa. The sequences obtained are similar to those of Diploptera punctata and Periplaneta americana reported previously. The precursors of all these cockroach species are similar in size, and the organization of the ASTs that they contain (there are 13 or 14, depending on the species) have been conserved. With the sequences of these precursors, and using the homologous sequence in the orthopteran Schistocerca gregaria as an outgroup, a phylogenetic analysis using parsimony was carried out. The dendrograms obtained from these analyses, using the amino acid as well as the nucleotide sequences, are comparable with current models for cockroach phylogeny. Parsimony analysis was also used to study the genealogy of the different ASTs within the same precursor. Results suggest that the AST sequences were generated through a process of internal gene duplication which occurred before these species diverged from each other in evolutionary time.