Fig. 4

Overexpression PtWS/DGAT in P. tricornutum. a Construct of the P. tricornutum expression vector. PfcpA, promoter of fcpA gene; His tag, 6 × His tag; TfcpA, terminator of fcpA gene; PfcpB, promoter of fcpB gene; bar, the herbicide basta-resistant gene. b Quantitative transcriptional levels of PtWS/DGAT in the PtWS/DGAToe and WT cells. Inset, Southern blotting of PtWS/DGAToe with the PtWS/DGAT gene probe or the bar gene probe. c Immunodetection of PtWS/DGAT-6 × Hisfusion protein with His-tag antibodies. d TLC analysis of wax ester in PtWS/DGAToe. PtWDoe PtWS/DGAT overexpression P. tricornutum, WT the wild-type P. tricornutum, −N0 nitrogen replete culture, −N10 nitrogen depletion for 10 days. TAG and wax ester were separated from total lipid by scraping their spots from TLC plates. The FA composition of TAG and wax ester was analyzed by GC–MS