The Finding of a Group IIE Phospholipase A2 Gene in a Specified Segment of Protobothrops flavoviridis Genome and Its Possible Evolutionary Relationship to Group IIA Phospholipase A2 Genes

Toxins

Kazuaki Yamaguchi⁴  Takahito Chijiwa⁴  Naoki Ikeda⁴  Hiroki Shibata²  Yasuyuki Fukumaki²  Naoko Oda-Ueda¹  Shosaku Hattori³  Motonori Ohno⁴ 

[1] Department of Biochemistry, Faculty of Pharmaceutical Sciences, Sojo University, Kumamoto 860-0082, Japan; E-Mail:;Medical Institute of Bioregulation, Research Center of Genetic Information, Kyushu University, Fukuoka 812-8582, Japan; E-Mails:;Institute of Medical Science, University of Tokyo, Oshima-gun, Kagoshima 894-1531, Japan; E-Mail:;Department of Applied Life Science, Faculty of Bioscience and Biotechnology, Sojo University, Kumamoto 860-0082, Japan; E-Mails:

关键词: group IIE phospholipase A₂;    venom;    evolution;    gene cluster;    comparative genomics;   

DOI  :  10.3390/toxins6123471

来源: mdpi

【 摘 要 】

The genes encoding group IIE phospholipase A₂, abbreviated as IIE PLA₂, and its 5' and 3' flanking regions of Crotalinae snakes such as Protobothrops flavoviridis, P. tokarensis, P. elegans, and Ovophis okinavensis, were found and sequenced. The genes consisted of four exons and three introns and coded for 22 or 24 amino acid residues of the signal peptides and 134 amino acid residues of the mature proteins. These IIE PLA₂s show high similarity to those from mammals and Colubridae snakes. The high expression level of IIE PLA₂s in Crotalinae venom glands suggests that they should work as venomous proteins. The blast analysis indicated that the gene encoding OTUD3, which is ovarian tumor domain-containing protein 3, is located in the 3' downstream of IIE PLA₂ gene. Moreover, a group IIA PLA₂ gene was found in the 5' upstream of IIE PLA₂ gene linked to the OTUD3 gene (OTUD3) in the P. flavoviridis genome. It became evident that the specified arrangement of IIA PLA₂ gene, IIE PLA₂ gene, and OTUD3 in this order is common in the genomes of humans to snakes. The present finding that the genes encoding various secretory PLA₂s form a cluster in the genomes of humans to birds is closely related to the previous finding that six venom PLA₂ isozyme genes are densely clustered in the so-called NIS-1 fragment of the P. flavoviridis genome. It is also suggested that venom IIA PLA₂ genes may be evolutionarily derived from the IIE PLA₂ gene.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.