辣椒BiP家族基因特性分析及CaBiP1在非生物胁迫中的功能鉴定

发布时间：2018-06-19 01:43

本文选题：辣椒 + BiP基因　；参考：《西北农林科技大学》2017年硕士论文

【摘要】：各种生长逆境造成的植物体蛋白结构的破坏和错误折叠,严重影响着植物的生长发育。BiP蛋白因为能够缓解由错误折叠蛋白的积累导致的内质网胁迫,在植物抵抗逆境过程中发挥着重要作用。同时,Bi P作为分子伴侣参与到内质网胁迫所激发的未折叠蛋白响应(UPR)进程,多个研究认为其参与到了抵抗蛋白错误折叠的内质网保护机制中。在本研究中,我们分析了三个辣椒Bi P基因(CaBiP1,CaBiP2和CaBiP3)的表达模式以及氨基酸序列结构。结果显示了三个基因的氨基酸序列拥有BiP蛋白所必需的保守功能域,但是在保守基序motif和内含子外显子分布方面,CaBiP3相对于CaBiP1和CaBiP2具有部分的差异。正常和胁迫条件下,CaBiP1和CaBiP2的表达模式说明它们属于组成性基因;而CaBiP3主要在特定的胁迫条件下表达,属于诱导型基因。CaBiP1的过表达加强了转基因拟南芥的抗非生物胁迫能力。非生物胁迫下转基因植株相对更高的发芽率、根长、成活率、可溶性蛋白含量以及失水率的降低,未折叠蛋白途径被激活均证明了抗胁迫能力的增强。病毒诱导的基因沉默(VIGS)在转录水平上大大降低CaBiP1的表达,降低了辣椒抵抗逆境胁迫(热胁迫、盐胁迫和渗透胁迫)以及二硫苏糖醇(DTT)引发的内质网胁迫的能力。这些结果由沉默植株叶片中增加的H2O2积累量、丙二醛(MDA)含量、相对电导率(REL)、失水率以及降低的可溶性蛋白含量得以证明。我们的结果为CaBiP家族基因在不同调节机制中功能的进一步研究奠定了基础,以及证明了CaBiP1基因在辣椒植株在应对非生物胁迫过程中发挥重要作用。
[Abstract]:The destruction and misfolding of plant protein structure caused by various growth stresses seriously affect the growth and development of plants. BiP protein can alleviate the endoplasmic reticulum stress caused by the accumulation of misfolded proteins. It plays an important role in plant resistance to stress. At the same time, BiP, as a molecular chaperone, is involved in the UPR-responsive process of unfolded proteins stimulated by endoplasmic reticulum stress, which is considered to be involved in the protection mechanism of endoplasmic reticulum against protein misfolding. In this study, we analyzed the expression patterns and amino acid sequence structure of three Pepper BiP genes, CaBiP1, CaBiP2 and CaBiP3. The results showed that the amino acid sequences of the three genes possessed the conserved functional domains necessary for the bip protein, but there were some differences between CaBiP3 and CaBiP1 and CaBiP2 in the distribution of conserved motifs motif and intron exons. The expression patterns of CaBiP1 and CaBiP2 under normal and stress conditions indicated that they belonged to constitutive genes, while CaBiP3 was mainly expressed under specific stress conditions, and the overexpression of the inducible gene .CaBiP1 enhanced the ability of transgenic Arabidopsis thaliana to resist abiotic stress. The relative higher germination rate, root length, survival rate, soluble protein content and water loss rate of transgenic plants under abiotic stress, and the activation of unfolded protein pathway proved the enhancement of resistance to stress. Virus-induced gene silencing significantly reduced the expression of CaBiP1 at the transcriptional level, and reduced the ability of capsicum to resist stress induced by heat, salt and osmotic stress, as well as endoplasmic reticulum stress induced by dithiothreitol (DTT). These results were demonstrated by the increased H _ 2O _ 2 accumulation in leaves of silencing plants, the content of malondialdehyde (MDA) MDAs, the relative electrical conductivity (REC), the water loss rate and the reduced soluble protein content. Our results laid a foundation for the further study of the function of CaBiP family genes in different regulatory mechanisms and demonstrated that CaBiP1 gene plays an important role in the response of pepper plants to abiotic stress.
【学位授予单位】：西北农林科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S641.3

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