在水分的跨膜运输过程中，植物水通道蛋白起到非常重要的作用。有充足的可利用的有效水是嫁接成活的关键。本课题组利用cDNA-AFLP技术在山核桃嫁接成活过程中克隆到一个质膜水通道蛋白CcPIP，在前期研究中，我们发现该基因在山核桃嫁接成活的水分运输过程中起到表达调控的作用，并在预实验中观察到ABA和盐胁迫处理抑制水通道蛋白表达。本项目拟采用分子生物学、免疫胶体金定位技术等方法，从整体－组织－细胞三个层次，观察山核桃质膜水通道蛋白CcPIP表达特性对山核桃嫁接成活过程的影响，来阐明这一基因在砧穗联合效应中的作用及其与维管束桥形成的相互关系，不仅丰富了水通道蛋白基因家族的基因信息，为水通道蛋白的研究提供了良好的物质基础，而且有助于揭示CcPIP影响山核桃嫁接成活的作用机制和山核桃嫁接过程水分跨膜运输机制，为山核桃等木本植物园艺化栽培提供一定的理论基础。

Plant aquaporins play a very important role in the water movement across the membrane. Plenty of available water is the key to grafting. A plasma membrane intrinsic protein CcPIP in hickory (Carya cathayensis) during graft process was cloned using cDNA-AFLP. We found that CcPIP play a role of gene expression and regulation in water movement during graft process, and also observed that ABA and salt stress can inhibit gene expression. In this project, we will use the molecular biology and immuno-gold technique to observe the effect of CcPIP on grafting, illustrate the role of this gene on the combined effect of rootstock-scion and clarify its relationship with the formation of vascular bridge from three levels of whole - tissue - cells. It will not noly enlarge the information of the aquaporin gene family and provide a basis for aquaporin research, but also benefit to uncover the mechanism of water movement across the membrane and the function of CcPIP in hickory during graft process, and provide a theoretical basis for horticulture cultivation of hickory and other woody plants.