该研究以不结球白菜(Brassica campestris L.ssp.chinensis Makino)自交不亲和系品种‘矮脚黄’为实验材料,利用VIGS技术将BcMLPK基因构建到pTY载体,进行定量分析,研究其在自交不亲和中的功能。结果表明:(1)BcMLPK基因序列长为1 443 bp,编码480个氨基酸,将BcMLPK蛋白氨基酸序列与其他物种的MLPK氨基酸比较表明,BcMLPK基因与其他物种中该基因具有高度保守的结构域。(2)成功构建pTY-BcMLPK载体,采用基因枪法侵染‘矮脚黄’,其新生的真叶有明显的花叶症状,选取发病的叶片及花蕾进行实时定量qRT-PCR,发现侵染的植株中BcMLPK基因表达量约为对照组的50%。(3)花期对植株进行自交授粉,实验组有明显的结荚现象,而对照组则出现雌蕊未能明显伸长,显示受精异常的现象;统计结果表明实验组的自交不亲和指数和结实率均高于对照组。研究表明,不结球白菜MLPK基因的沉默能够抑制‘矮脚黄’自交不亲和相关基因BcMLPK的转录水平表达。
In this study, the self-incompatible line variety ’Aijiaohuang’ of Brassica campestris L. ssp. chinensis Makino was used as the experimental material. The BcMLPK gene was constructed into the pTY vector by VIGS technique and quantitatively analyzed, to research the function of BcMLPK gene in self-incompatibility. The results showed that:(1) the BcMLPK gene sequence has a length of 1 443 bp and encodes 480 amino acids. Comparison of the amino acid sequence of BcMLPK protein with MLPK amino acids of other species indicates that the BcMLPK gene has a highly conserved domain with other genes.(2) Construction of pTY-BcMLPK vector, using the gene gun method to infect ’Aijiaohuang’, the new true leaves have obvious symptoms such as mosaic, select the diseased leaves and flower buds for real-time quantitative qRT-PCR identification. The expression level of BcMLPK gene in the infected plants was about 50% of the control group.(3) The plants were self-pollinated at the flowering stage, and the experimental group had obvious pod-forming phenomenon, while the control group showed the pistil failed to elongate significantly, indicating abnormal fertilization. The statistical results showed that the self-incompatibility index and seed setting rate of the experimental group were higher than those of the control group. Studies have shown that the silencing of MLPK gene is able to inhibit the expression of BcMLPK transcriptional level of the self-incompatible gene of ’Aijiaohuang’.
Acta Botanica Boreali-Occidentalia Sinica
Brassica campestris L.ssp.chinensis Makino