Fig. 1

Vectors for G6PDH overexpression and antisense knockdown in P. tricornutum. a Schematics of pPha-PtG6PDH-OE and pPha-PtG6PDH-AS vectors for overexpression or silencing of P. tricornutum G6PDH. The cDNA (amplified using G6Poe_fw and G6Poe_rv) were digested with EcoRI and HindIII and subsequently ligated in sense orientation into the EcoRI–HindIII sites of pPha-T1, which are located downstream of the fcpA promoter, resulting in the final transformation vectors pPha-PtG6PDH-OE; the amplicons (amplified using G6Pas_fw and G6Pas_rv) were digested with EcoRI and HindIII and then ligated in antisense orientation of pPha-T1 and finally resulted in the vector pPha-PtG6PDH-AS. b Preliminary molecular analysis of transgenic P. tricornutum strains. Line 1 to line 5, PCR analysis of the resistant gene sh ble in the wild-type, PtG6PDH-OE1, PtG6PDH-OE2, PtG6PDH-S1 and PtG6PDH-S2 with primers ble_fw and ble_rv, respectively. Line 6 to line 8, PCR analysis in the wild-type, PtG6PDH-OE1 and PtG6PDH-OE2 with primers OE_fw1 and OE_rv1. Line 9 to line 11, PCR analysis in the PtG6PDH-S1, PtG6PDH-S2 and the wild-type strain using primers AS_fw1 and AS_rv1. M, 2-kb DNA size marker