title: Structural characteristics and evolution of a novel venom phospholipase A2 gene from Protobothrops flavoviridis.
abstract: A novel phospholipase A(2) (PLA(2)) gene, named PfPLA 6, was found in a 6,328-bp NIS-1(5')-a segment in the Protobothrops flavoviridis (Habu, Crotalinae) genome. A comparison of the aligned nucleotide sequences of Viperidae (Viperinae and Crotalinae) venom PLA(2) genes, including PfPLA 6, revealed the deletion of a 12-bp segment called S1EX 1 and a 55-bp segment called S2EX 1 in exon 1 and the interposition of a 219-bp segment called SINT 2 (SINE) in intron 2. A classification of Viperidae PLA(2) genes based on these structural modes indicated that the A-type genes (without SINE), including PfPLA 6, are evolutionarily ancestral to the B-type (Viperinae) and C-type (Crotalinae) PLA(2) genes (both with SINE). Since PfPLA 6 is a pseudogene, an active prototype of PfPLA 6 can be assumed to be the ancestral PLA(2) gene. Putative evolutionary processes from this A-type prototype PLA(2) gene to descendent PLA(2) genes are discussed.
authors.affiliation: Department of Applied Life Science, Faculty of Bioscience and Biotechnology, Sojo University, Ikeda, Kumamoto, Japan. chijiwa@life.sojo-u.ac.jp
authors.forename: Takahito
authors.initials: T
authors.lastname: Chijiwa
authors.forename: Naoki
authors.initials: N
authors.lastname: Ikeda
authors.forename: Haruna
authors.initials: H
authors.lastname: Masuda
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Hara
authors.forename: Naoko
authors.initials: N
authors.lastname: Oda-Ueda
authors.forename: Shosaku
authors.initials: S
authors.lastname: Hattori
authors.forename: Motonori
authors.initials: M
authors.lastname: Ohno
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003435:Crotalid Venoms / Q000201:enzymology* / Q000235:genetics; D019143:Evolution, Molecular; D006579:Heterozygote; D007527:Isoenzymes / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D054467:Phospholipases A2 / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D011544:Pseudogenes / Q000235:genetics; D017422:Sequence Analysis, DNA; D017384:Sequence Deletion; D017819:Viperidae / Q000235:genetics*
chemical_list: D003435:Crotalid Venoms; D007527:Isoenzymes; D054467:Phospholipases A2