甘蓝型油菜GPAT6基因功能初步探究

Preliminary Study on the Function of GPAT6 Gene in Brassica napus L.

甘油-3-磷酸酰基转移酶6 (GPAT6)是三酰甘油生物合成的限速酶,催化三酰甘油合成的起始步骤,在植物中参与了三酰甘油的生物合成,以往的研究发现GPAT6在植物的花发育过程中起着重要的作用。但GPAT6在油菜种子萌发和幼苗生长中的作用未见报道。本试验以花粉介导的转基因方法将特异干扰GPAT6基因的GPAT6-RNAi载体转入油菜7B基因组中,构建GPAT6-RNAi转基因植株,并以该转基因油菜为材料,研究GPAT6基因在种子萌发和幼苗生长中的作用,并对GPAT6基因编码的蛋白质进行了生物信息学分析。在油菜幼苗期提取叶片总DNA,进行PCR检测,共得到15株转基因植株。与野生型植株相比,转基因植株种子萌发时间延迟,幼苗出真叶晚。生物信息学研究发现,GPAT6基因cDNA (complementary DNA)全长1 631 bp,开放阅读框(open reading frame, ORF)长1 506 bp,编码501个氨基酸。GPAT6为不稳定疏水性蛋白,无信号肽,是一个跨膜蛋白。蛋白质的主要二级结构是无规则卷曲,占38.32%。GPAT6基因在种子萌发和开花期高表达。本研究初步表明,GPAT6基因在种子萌发和幼苗生长中具有重要作用,干扰其表达后会导致三酰甘油的合成受阻,储存减少,进而影响植株种子萌发及后期生长的能量供应和积累。这一研究为提高作物的含油量提供了帮助。

Glycerol-3-phosphate acyltransferase(GPAT6) is the rate-limiting enzyme for triacylglycerol biosynthesis, catalyzes the initial step of triacylglycerol synthesis, and participates in the biosynthesis of triacylglycerol in plants. It is found that GPAT6 plays an important role in the flower development of plants. However, the role of GPAT6 in rape seed germination and seedling growth has not been reported. In this experiment, the GPAT6-RNAi vector with specific interference to GPAT6 gene was transferred into the rapeseed 7 B genome by pollen-mediated transgenic method to construct GPAT6-RNAi transgenic plants, and the GPAT6 gene was studied in seed germination using the transgenic rapeseed as material. The role of seedling growth, and bioinformatics analysis of the protein encoded by the GPAT6 gene. Total leaf DNA was was extracted at the seedling stage of rape, and polymerase chain reaction(PCR) was carried out to obtain 15 transgenic plants. Compared with wild-type plants,the seed germination time of the transgenic plants was delayed, and the seedlings were later leaves. Bioinformatics research finds that the full length of GPAT6 gene c DNA is 1 631 bp, and the open reading frame(ORF) is long1 506 bp, encoding 501 amino acids. GPAT6 is an unstable hydrophobic protein with no signal peptide and is a transmembrane protein. The main secondary structure of the protein is random coil, accounting for 38.32%. The GPAT6 gene is highly expressed during seed germination and flowering. This study preliminarily showed that GPAT6 gene plays an important role in seed germination and seedling growth. Interfering with its expression will lead to the inhibition of triacylglycerol synthesis and storage, which will affect the energy supply and accumulation of seed germination and later growth. This research could be helpful for improving the oil content of crops.