橡胶树橡胶生物合成调控相关基因的表达相关性分析

Correlation analysis on expression of genes related to rubber biosynthesis regulation of rubber tree

关键词:  巴西橡胶树, 割胶, 茉莉酸信号途径, 橡胶生物合成, 基因表达, Pearson相关

Key words:  Hevea brasiliensis, tapping, jasmonate signaling, rubber biosynthesis, gene expression, Pearson correlation

摘要:

该文通过qPCR获得了正常割胶条件下,9个茉莉酸信号途径关键环节基因HbCOI1、HbJAZ1、HbJAZ2、HbJAZ3、HbMYC1、HbMYC2、HbMYC3、HbMYC4、HbMYC5和6个橡胶生物合成相关基因HbHRT2、HbSRPP、HbREF、HbHMGR1、HbHRT1、HbGAPDH在5个橡胶树魏克汉种质和5个1981'IRRDB种质胶乳中的表达数据; 通过皮尔逊相关系数分析了这15个基因彼此间的表达相关性,分别获得105对基因的双变量相关系数(r12)和偏相关系数(r12.3),所有105对基因的双变量相关系数(︱r12︱)和偏相关系数(︱r12.3︱)的平均值分别为0.486 ± 0.220和0.304 ± 0.211,达到0.05的差异显著水平。其中,r12与r12.3方向相同的63对(60%),方向相反的42对(40%); ︱r12︱<︱r12.3︱的23对(21.905%),︱r12︱>︱r12.3︱的82对(78.095%); 双变量相关显著性P<0.05的76对(72.38%),P<0.01的59对(56.19%); 偏相关显著性P<0.05的21对(20%),P<0.01的16对(15.24%)。结果显示,这两条途径中的基因表达彼此相关,这为基因表达谱分析中普遍采用的前提假设“功能相关基因的表达相关”提供了进一步的实验证据,可用于挖掘、筛选和预测与橡胶生物合成相关的未知基因,为研究橡胶树产量形成的分子调控机理提供理论基础。

Abstract:

Tapping-enhanced rubber biosynthesis is closely related to the activation of jasmonic acid signaling in laticifer cells of rubber tree. The expression level of genes related to jasmonic acid signaling pathway and rubber biosynthesis were both positively correlated with the dry rubber yield. However, the exact relationship between the expression of genes involved in jasmonic acid signaling and rubber biosynthesis is not to be elucidated yet. In the present study, qPCR was used to analyze the expression of nine jasmonic acid signaling genes, HbCOI1, HbJAZ1, HbJAZ2, HbJAZ3, HbMYC1, HbMYC2, HbMYC3, HbMYC4, HbMYC5 and six rubber biosynthesis genes, HbHRT2, HbSRPP, HbREF, HbHMGR1, HbHRT1, HbGAPDH, in laticifer cells of five Wichham germplasms and five 1981'IRRDB germplasms following tapping them with S/2D d3 tapping system, Hb18S was used as internal reference gene. The correlation between these 15 genes was analyzed through Pearson correlation coefficient. The bivariate correlation coefficient(r12)and partial correlation coefficient(r12.3)of 105 gene pairs were obtained with the mean ± standard deviation of 0.486 ± 0.220 and 0.304 ± 0.211, respectively. Among them, 63 gene pairs(60%)with r12 in the same direction as r12.3 and 42 genes pairs(40%)in the opposite direction; In the degree of correlation, 23 gene pairs(21.905%)with | r12 | less than | r12.3 |, and 82 gene pairs(78.095%)with | r12 | greater than | r12.3 |. There 76 gene pairs(72.38%)bivariate correlation coefficient(r12)were significant correlation at P<0.05 level and 59 gene pairs(56.19%)at P<0.01 level. In contrast, there less partial correlation coefficient(r12.3)were significant correlation at P<0.05 level(21pairs, 20%)and P<0.01 level(16 pairs, 15.24%). These results suggested that the expression of genes involved in these two pathways were related to each other, which provides a further evidence for the assumption that “expression correlation of functional related genes”, which is widely adopted in gene expression profile analysis. It can be used for excavating, screening and predicting unknown genes related to rubber biosynthesis, as well as provides a theoretical basis for studying the molecular regulation mechanism of rubber yield formation in Hevea brasiliensis.