中文摘要：

高丹草是代表性的利用杂种优势的饲用牧草,本研究以杂种高丹草及其亲本三叶期叶片为试材,采用双向电泳、质谱技术及生物信息学分析方法,进行了蛋白质组学研究。凝胶上检测到的可重复蛋白点400多个,其中杂种与亲本间达到了显著水平的差异蛋白点34个,包括显性（单亲沉默3个,偏高亲表达17个,偏低亲表达5个）和超显性表达（特异表达1个,超高亲表达6个,超低亲表达2个）模式,因此推测显性和超显性效应共同促进高丹草杂种优势的形成,且显性效应作用更大。同时,成功鉴定出其中的27个蛋白点涉及到8个功能类别,即光合作用、碳水化合物代谢、胁迫响应、ATP合成、蛋白质合成、电子转移、信号转导及未知蛋白。高丹草所占比例最大的光合蛋白多数呈上调表达,表明杂种叶片光合作用增强进而同化更多的有机物是杂种优势形成的主要原因。网络互作的关键节点蛋白为杂种优势特异蛋白的基因操作提供了靶蛋白。本研究在蛋白质水平为高丹草杂种优势分析提供了理论依据,也为其他饲草作物的相关研究提供了理论参考。

英文摘要：

Sorghum-sudangrass hybrids are typically used for studying heterosis in forage crops. In this study, we carried out proteomic research on sorghum-sudangrass hybrids and their parents at the three-leaf stage by two dimensional electrophoresis-based proteomics and bioinformatic methods. More than 400 protein spots were detected, in which 34 proteins showed significant differences between hybrid and parents in expression, including dominant expression（showing three single-parent silent, seventeen high-parent and five low-parent expression） and overdominant expression（showing one hybrid-specific, six above-high-parent, two below-low-parent expression）. Thus, we speculated that dominant and overdominant effects play key roles, and dominant effect is a major factor in the formation of heterosis in sorghum-sudangrass hybrid. Moreover, 27 out of 34 proteins were related to eight functional categories, i.e., photosynthesis, carbohydrate metabolism, stress response, ATP synthesis, protein synthesis, electron transfer, signal transduction and unknown. The up-regulated photosynthetic proteins were the biggest category, which indicates that photosynthesis in the leaves of sorghum-sudangrass hybrid is enhanced resultig in producing more organic matter, so that showing heterosis. The identified key node proteins in the interaction networks were the potential target proteins for future genetic manipulation of the specific proteins of heterosis. Our findings provide a theoretical basis on heterosis analysis of sorghum-sudangrass hybrids, which is potentially useful for other forage plants.