Characterization of Arabidopsis secretory phospholipase A2-gamma cDNA and its enzymatic properties.
Plant secretory phospholipases A(2) (sPLA(2)s) probably play important roles in phospholipid signaling based on the data reported from other organisms, but their functions are poorly understood because of the lack of cloned sPLA(2) genes. In this study, we cloned and characterized an Arabidopsis secretory phospholipase A(2)-gamma (AtsPLA(2)-gamma) cDNA, and examined its enzymatic properties. The recombinant protein of AtsPLA(2)-gamma showed maximal enzyme activity at pH 8.0, and required Ca(2+) for activity. Moreover, AtsPLA(2)-gamma showed sn-2 position specificity but no prominent acyl preference, though it showed head group specificity to phosphatidylethanolamine rather than to phosphatidylcholine. AtsPLA(2)-gamma was found to predominate in the mature flower rather than in other tissues, and subcellular localization analysis confirmed that AtsPLA(2)-gamma is secreted into the intercellular space.
Bahn
Sung Chul
SC
School of Life Sciences and Biotechnology, Korea University, Seoul, South Korea.
Lee
Hyoung Yool
HY
Kim
Hae Jin
HJ
Ryu
Stephen B
SB
Shin
Jeong Sheop
JS
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics; D002118:Calcium / Q000378:metabolism; D003001:Cloning, Molecular; D035264:Flowers / Q000201:enzymology; D020869:Gene Expression Profiling; D054513:Group IV Phospholipases A2; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D019697:Onions / Q000166:cytology / Q000201:enzymology; D010741:Phospholipases A / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D054467:Phospholipases A2; D021381:Protein Transport; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D013379:Substrate Specificity
D012333:RNA, Messenger; D010741:Phospholipases A; D054513:Group IV Phospholipases A2; D054467:Phospholipases A2; D002118:Calcium