Abstract:To understand the regulation of 20S proteasome α subunit A (POA1) gene on lipid metabolism in Chlamydomonas reinhardtii, the expression of CrPOA1 in C. reinhardtii were analyzed by qRT-PCR under low nitrogen conditions. The fragment of CrPOA1 in C. reinhardtii CC245 was cloned, and then was used to construct a CrPOA1 RNA interference vector and transferred into C. reinhardtii. The cell dry weight and lipid content of transgenic algae strains was measured. The CDs sequence was cloned. The fusion expression vector of CrPOA1-GFP was constructed and transformed into onion epidermal cells for subcellular localization. The results showed that CrPOA1 mRNA level of C. reinhardtii in low nitrogen culture was significantly decreased than that in normal culture (P<0.01). The CrPOA1 mRNA level of RNAi transgenic algae was significantly decreased by 79.36%-85.35%. The cell dry weight of CrPOA1 RNAi transgenic algae was not significantly different from the control (maa7). The lipid content was significantly decreased by 6.38%-24.63% compared with the control (maa7). The CrPOA1 might local in nucleus. So, it was suggested that CrPOA1 could be involved in lipid metabolism of C. reinhardtii.