根端干细胞是根各种组织的细胞来源，生长素信号调控根端分生组织和干细胞池的维持。基因表达的转录调控在这一过程中起重要作用，但是基因表达转录后调控如何调控生长素信号以及根端分生组织和干细胞池的维持还极少了解。Pre-mRNA的剪接包括组成型剪接和可变剪接，是基因表达转录后调控的重要步骤，参与植物发育的调控。Defective Root Development (DER) 是酵母剪接因子PRP17的同源基因。我们发现拟南芥的der突变体根端分生组织和干细胞池的维持异常，但苗端分生组织无明显异常，表明DER特异的调控根端分生组织和干细胞池的维持。初步研究显示DER参与生长素信号。本项目在前期工作的基础上，鉴定DER调控哪些基因pre-mRNA的可变剪接，研究这些基因在调控生长素信号以及根端分生组织和干细胞池稳态维持中的作用机理。研究结果将揭示可变剪接在根端分生组织和干细胞池稳态调控中的分子机理。

Auxin signaling is critical for the maintenance of root apical meristem and stem cells which are the sources for the tissues of root. Auxin plays its roles at multiple levels by its biosynthesis, polar transport, perception, and signaling transduction in plants. Pre-mRNA splicing is an essential step for post-transcriptional regulation of gene expression, which has been involved in the regulation of growth and development and the acclimation to stresses. However, it is unknown how pre-mRNA splicing regulating the maintenance of apical meristem and stem cell in root. In our previous study, we identified an Arabidopsis mutant, defective root development (der), showing defect root development with abnormal maintenance of apical meristem and stem cells. DER is a homolog of yeast PRP17 regulating cell cycle by implicating in the second step of splicing. Our primary study showed that DER plays its roles by implicated in auxin signaling in root. In this project, we will dissect the molecular mechanism of DER regulating the maintenance of apical meristem and stem cells in root via pre-mRNA splicing.