A simple and efficient <i>in situ</i> RT-PCR method for detecting gene expression in specific cells of tea plant (<i>Camellia sinensis</i>) root

Currently, the field of tea plant biology is rapidly advancing, with numerous significant scientific inquiries being raised and investigated. Meanwhile, a substantial number of functional genes have been reported. However, due to the lack of certain <i>in vivo</i> validation techniques, much of the expression information for these functional genes is at the tissue level in tea plants and remains unclear at the cell-type level. In this study, an <i>in situ</i> PCR method for detecting gene expression heterogeneity in tea plant root cells is presented. A detailed description of the procedure and precautions involved in this method is provided and suggestions offered for addressing potential experimental challenges. Finally, the expression patterns of <i>CsGL3</i>, <i>CsCAT2,</i> and <i>CsAAP4</i> in tea plant root cells were taken as examples. The present results showed that <i>CsGL3</i> was predominantly expressed in root epidermal cells, while <i>CsCAT2</i> shows strong expression in pericycle and cortex. The expression of <i>CsAAP4</i> was not detected in root cells. These findings are consistent with previous reports, indicating that this method is feasible for the detection of gene expression patterns in tea plant root cells.