Phospholipases A(2) in the genome of the sea anemone Nematostella vectensis.
The genome of the sea anemone Nematostella vectensis (Nv) (Cnidaria, Anthozoa) was sequenced recently (Putnam et al., Science 317: 86, 2007). In the current study, 22 proteins of Nv were identified as putative phospholipases A(2) (PLA(2)) that showed up to 40-50% sequence identity with secreted or intracellular PLA(2)s including those of humans. Nv1-Nv6 PLA(2)s have identity with secreted human group (G)IB and GIIA PLA(2)s and PLA(2)s of the sea anemones Adamsia carciniopados and Urticina crassicornis. Nv7 and Nv8 PLA(2)s have identity with human and bee venom GIII PLA(2)s and Nv9 PLA(2) with GXIIA PLA(2). Nv10-Nv13 PLA(2)s show identity with GIX PLA(2) of Conus magus and bacterial PLA(2)s but no significant identity with any human PLA(2). Nv14 has identity with intracellular GIV PLA(2), Nv15 with GVII PLA(2), Nv16 and Nv17 with GVIII PLA(2), Nv18-Nv20 with GVI PLA(2), and Nv21 and Nv22 with patatin, respectively. The observations indicate that the cnidarian phospholipasome contains a rich array of orthologs of most types of animal PLA(2)s, and that many of the PLA(2)-driven vital functions prevail in these ancient metazoans. Cnidarian PLA(2)s may be considered as evolutionary precursors of PLA(2)s of higher animals.
Nevalainen
Timo J
TJ
Department of Pathology, University of Turku, Kiinamyllynkatu 10, FIN-20520 Turku, Finland.