Abstract

Lysophosphatidic acid acyltransferase (LPAAT) is a pivotal enzyme controlling the metabolic flow of lysophosphatidic acid into different phosphatidic acids in diverse organisms. Here we identified and cloned LPAAT from Crambe abyssinica Hochst. ex R. E. Fries (CaLPAAT, GenBank accession number EF208088). To study its function in vivo, CaLPAAT was introduced into Brassica napus by Agrobacterium. The expression profile of several genes in the glycerolipids synthesis pathway was determined by quantitative RT-PCR. Interestingly, higher expression of CaLPAATled to elevated expression of these genes. Further analysis of the fatty acyl compositions in the self-cross seeds of the T₁ generation demonstrated that they were at the similar level in both transgenic plants and their non-transgenic counterparts. However, the total oil content of transgenic seeds was increased. We conclude that CaLPAAT can be ectopically expressed in B. napus and increase its total oil content.

Key words: Brassica napus, Crambe abyssinica Hochst. ex R. E. Fries, lysophosphatidic acid acyltransferase, oil content.

Abbreviation

GP, Glycerol-3-phosphate; GPAT, glycerol-3-phosphate acyltransferase; LPA, lysophosphatidic acid; LPAAT, lysophosphatidic acid acyltransferase; PA, phosphatidic acid; CaLPAAT, cloned LPAAT from Crambe abyssinica Hochst. ex R. E. Fries; TGs, triacylglycerols; 6-BA, 6-benzylaminopurine; PCR, polymerase chain reaction; RT-PCR, reverse transcription-PCR.