节瓜全雌基因克隆与初步功能分析

节瓜是华南地区特色葫芦科作物，商品瓜采收期较长。全雌性材料因花期早、第一雌花节位低、早熟性和单株坐果数多，是节瓜早熟、高产、稳产的基础。但与黄瓜、甜瓜相比，节瓜遗传基础狭窄，全雌性分子研究尚未报道。本项目组前期发现节瓜全雌性是由单隐性基因控制，初步定位在Chr.8上1.5Mb内（SSR8C056-SSR8C018），含有41个候选基因，与节瓜CqWIP1基因分属不同染色体。拟在此基础上，精细定位全雌基因，结合进化树、生物信息学和同源基因功能分析，克隆候选基因；利用qRT-PCR、原位杂交和亚细胞定位分析候选基因的表达模式；通过过表达和基因编辑技术验证目的基因功能；利用RNA-Seq获得对照和转基因植株的差异基因，了解目的基因参与的信号通路，检测性别决定相关基因的表达量变化，初步分析目的基因的功能。本项目为阐明节瓜全雌性遗传调控机制提供理论参考，对于推动葫芦科性别决定机制研究具有重要意义。

Chieh-qua (Benincasa hispida Cogn. var. Chieh-Qua How) is a special cucurbit plant with long flowering time. Gynoecy shows early flowering time, low location, and more fruits per plant, which were basis for early maturity, high and stable yield in chieh-qua. Gynoecy, is important for increasing seed producing efficiency and production in chieh-qua. Compared with melon and cucumber, the genetic basis in chieh-qua is pretty poor and nearly no genetic studies on gynoecy were reported. We previously found that the chieh-qua was controlled by a single gene and primary mapped in 1.5Mb (including 41 candidate genes) betwween SSR8C056-SSR8C018 on Chr.8, which different with the homologous gene of CqWIP1. On the basis, we would fine map the gynoecious gene. The candidate gene is explored combing the phylogenetic analysis, bioinformatics and homologous gene function. Candidate gene function was identified by over-expressing and Crispr-Cas9. The qRT-PCR, RNA in-situ hybridization, and subcellular localization were carried out to analyze the expression pattern. The RNA-Seq was performed to screen several differentially expressed genes between control and transgenic plants and understand the gene expression model of candidate gene. Finally, the primary function is analyzed. These results will provide foundation for the molecular regulation and gynoecy breeding, and is helpful for enriching sex determination in cucurbitaceae.