石细胞是梨特有的，导致其果实品质低劣的特异性状，影响了我国梨产业的经济效益，果实内细胞的木质化是石细胞发生的根本原因。植物细胞的程序性死亡（PCD）及其木质化是由类Caspase蛋白Metacaspases（MCs）启动并执行的。前期工作中我们通过对梨基因组MCs家族的同源鉴定和系统发育分析，结合定量PCR及瞬时和稳定表达体系，初步明确PbMC1a/1b参与了梨果实细胞的木质化，石细胞发育可能是PCD过程。基于以上研究进展，本项目拟从PCD角度，鉴定梨石细胞发育过程中细胞形态和生化特征；研究PbMC1a/1b调控石细胞发育的分子机制，鉴定PbMC1a/1b的互作蛋白及其编码基因；探讨蛋白互作及转录共表达在PbMC1a/1b调控细胞启动木质化形成石细胞过程中的生物学功能。研究结果可望阐明梨石细胞发生的原因，拓展石细胞形成及调控机制研究，为提高梨果实品质，保障梨产业可持续健康发展提供理论保障。

Deposition of abundant stone cell clusters impacts poor quality in pear fruit, resulting in low benefits of this industry. The reason for this is the high lignification of the cells. Programmed cell death (PCD) and subsequent lignification of plant cells are always regulated by caspase-like proteases Metacaspases (MCs). In our previous study, with the aid of transient expression and stable expression system and qRT-PCR, we screened and identified PbMC1a/1b from pear genome, and found it also participated in cell lignification in pear. Basing on these results, cellular morphology and biochemical indicator will be surveyed during lignifying progress, and interaction proteins with PbMC1a/1b will also be further screened and identified in this research proposal, in order to investigate the co-expression networks of PbMC1a/1b, and its function in formation of stone cells. The potential finding will help us to expand our research on stone cells in pear, and also may give us some ideas on how to improve pear fruit quality.