茶树金属耐受蛋白基因的克隆与表达分析

Through the high Mn treatment of C. sinensis cultivar 'Yingshuang' and 'Longjing-changye', it was found that the 'Longjing-changye' had higher Mn tolerance than 'Yingshuang'. Mn tolerance of 'Longjing-changye' were analyzed using two-dimensional electrophoresis (2-DE) combined with matrix-assisted laser desorption ionization (MALDI)-time of flight (TOF)/TOF mass spectrometry (MS) analysis. A total of more than 700 protein spots were detected, and 20 protein spots were differentially expressed, in which 9 protein spots were down-regulated and 11 up-regulated. Further analysis of protein spots E20 indicated that the protein is related to metal tolerance. The CsMTP8 was obtained by rapid-amplification of cDNA ends (RACE) and reverse transcription PCR (RT-PCR). The ORF of CsMTP8 is 1218 bp, encoding 405 amino acids with a molecular mass of 44.5 kDa. Evolutionary relationship analysis showed that CsMTP8 had high homology with metal tolerance protein from other plant species, such as Arabidopsis thaliana, rice and Stylosanthes hamate. Subcellular localization results showed that CsMTP8 localized to the plasma membrane. Quantitative real-time PCR (qRT-PCR) results showed that the expression of CsMTP8 in leaves was higher than that in roots, stems and flowers under basal Mn concentration, while excess Mn significantly up-regulated the expression of CsMTP8 in C. sinensis leaves (P < 0.05).