| Camellia sinensis,as a perennial arbor plant,prefers light and warm condition,but fears of exposure and cold.The etiolated symptom often occur in tender shoots under natural condition.The yellowing tender shoots of light-sensitive ’Huangkui’ tea plant will turn green with low light intensity.Through gene expression screening techniques and function verification experiment,we found that chloroplast-localized small heat shock protein CsHSP24.6 interacted with plastid transcriptionally active protein CspTAC5,which play important roles on the green restoration of ’Huangkui’ tea plant yellowing tender shoots.The results were as follows:1.The transcriptome sequencing and qRT-PCR technique were used to analyze the expression specificity of CsHSP24.6 and CspTAC5.The results showed that the expression of CsHSP24.6 and CspTAC5 may related with the phenomenon of the green restoration of’Huangkui’ tea plant yellowing tender shoots.The genes of CsHSP24.6 and CspTA C5 were upregulated in ’ Anjibai’ and ’Huangkui’ tea plant,the color of their tender leaves were chlorotic compared to ’ Shuxhazao’ tea plant.After shading treatment,the shoots color of’Huangkui’ tea plant turned green.The contents of chlorophyll and carotenoid were increased.The expression level of CsHSP24.6,CspTAC5 and the genes related to chlorophyll and carotenoid synthesis were upregulated.2.In the functional verification experiment,the CsHSP24.6 and CspTAC5 genes were overexpressed in Arabidopsis thaliana plants.Results showed that the chloroplasts of transgenic plants were less damaged than the wild type plants under high temperature and height light stress,although their phenotypes were similar.This indicated that the expression of the genes CsHSP24.6 and CspTAC5 were related to the photosynthetic apparatus.3.The results of transient expression in N.benthamiana assay showed that CsHSP24.6 protein and CspTAC5 protein were located at chloroplast.The results of the Bimolecular Fluorescence Complementarity and GST-pull down experiments showed that the two proteins had interactions. |
