Indian Journal of Plant Physiology

Microsomal ω-6 desaturase encoded by fad2-1 gene catalyzes the production of polyunsaturated fatty acids in seed storage lipids. A cDNA library was constructed in λTriplEx2 vector using poly (A) RNA isolated from developing seeds (19–26 DAF) of Glycine max L. The putative clones from library screening were converted into plasmid clones following in vivo excision and analyzed for insert size by restriction digestion. A positive clone PR2 with largest insert size spanning a total of 1139 bp revealed a 3’ UTR region of 184 bp specific to fad2-1. Conceptual translation indicated an open reading frame of 955bp encoding a 317 amino acid protein with a predicted molecular weight of 37kD. A high degree of sequence identity was found with Glycine max cDNA for -6-desaturase and with fad2-1 of Arachis hypogea. PR2 was also used as a labelled probe to analyse the expression of fad2-1 transcripts by northern blotting. High levels of fad2-1 mRNA transcripts were detected at the mid maturation stages of seed development (19–26 DAF).