Abstract
Phospholipase A(2) (PLA(2)) belongs to class of lipolytic enzymes (EC 3.1.1.4). Lysophosphatidic acid (LPA) and free fatty acids (FFAs) are the products of PLA(2) catalyzed hydrolysis of phosphoglycerides at sn-2 position. LPA and FFA that act as second mediators involved in the development and maturation of plants and animals. Mining of flax genome identified two phospholipase A(2) encoding genes, viz., LusPLA (2) I and LusPLA (2) II (Linum usitatissimum secretory phospholipase A(2)). Molecular simulation of LusPLA(2)s with already characterized plant sPLA(2)s revealed the presence of conserved motifs and signature domains necessary to classify them as secretory phospholipase A(2). Phylogenetic analysis of flax sPLA(2) with representative sPLA(2)s from other organisms revealed that they evolved rapidly via gene duplication/deletion events and shares a common ancestor. Our study is the first report of detailed phylogenetic analysis for secretory phospholipase A(2) in flax. Comparative genomic analysis of two LusPLA(2)s with earlier reported plant sPLA(2)s, based on their gene architectures, sequence similarities, and domain structures are presented elucidating the uniqueness of flax sPLA(2).