一个新的黄瓜表皮毛发育基因NWD的克隆及功能分析

Cucumber is an important vegetable crop, no trichome cucumber is less polluted and convenient for cleaning, which has become an important factor in cucumber quality breeding and marketing. no wart development (nwd) was a stable genetic mutant with smooth fruit, which was controlled by a single recessive nuclear gene. Using map-based cloning strategy, the NWD gene was mapped to a new unreported region-128kb interval in Chromosome 1. Base on these findings, a fine mapping will be simultaneously carried out to clone this target gene; the mutation phenotype will be further investigated using cell biology analysis methods; subcellular localization, transgenic cucumber and regulator network will be performed to ascertain NWD function and molecular mechanism. Through this research, we expected to reveal the relationship of NWD with cucumber trichome development in the theory, to provide theoretical support for cucumber genetic improvement in the application.

黄瓜是重要的蔬菜作物，无毛黄瓜污染少，清洗方便，已成为黄瓜品质育种和市场销售的重要因素。no wart development（nwd）是前期获得的一个稳定遗传的无毛突变体，果实光滑无毛，受单隐性核基因控制。通过图位克隆策略已将其定位在1号染色体128kb的区间内，该区间之前未见表皮毛发育相关基因的报道。本项目拟在已有的工作基础上通过精细定位克隆NWD基因，细胞生物学方法分析突变表型，亚细胞定位、转基因黄瓜及调控网络的研究阐明其在黄瓜表皮毛发育中的功能及分子机制。通过本研究，可望在理论上揭示该基因与黄瓜表皮毛发育之间的关系，在应用上为黄瓜的遗传改良提供理论支持。

no wart development（nwd）是前期获得的一个稳定遗传的无毛突变体，受单隐性核基因控制。nwd突变体果实光滑无毛，且其叶片、茎、卷须、和花萼表面均没有表皮毛的覆盖。进一步研究发现，突变体株高、净光合速率、叶绿素a、抗氧化酶CAT和SOD和可溶性蛋白的含量显著性低于野生型，而丙二醛显著性高于野生型。NWD基因定位及分型分析显示，外显子区域2处非同义突变SNP27927016和SNP28111797与突变体表型共分离，编码磷酸核糖转移酶基因CsaV3_3G032350为目的候选基因，过表达野生型和突变体差异表达基因WRKY50促进拟南芥矮化、早花、多分枝、多果荚和叶片表皮毛数量降低，VIGS沉默WRKY50基因黄瓜叶片的表皮毛数量显著性上升，以上结果为黄瓜的遗传改良提供理论支持。