Molecular Cloning and Sequence Analysis of △~(12)-fatty Acid Desaturase in Peanut(Arachis hypogaea L.)

To study the function of peanut △12-fatty acid desaturase,the full-lengh cDNA of AhFAD was amplified by RACE from peanut seed.Sequence analysis found that the open reading frame encodes a protein with 379 amino acids and the molecular weight of deduced protein of AhFAD was 43 kDa.One highly conserved feature of all membrane-bound desaturases was the presence of three histidine boxes,with the general sequence HXXXH.The hydrophobicity analysis showed that the sequence of the encoded amino acids had two hydrophobic structures sharing the characteristics of membrane-anchored protein,which totally crossed the membrane four times.These analyses revealed the obtained sequence was Δ12-fatty acid desaturase.