日中性植物番茄CONSTANS类似蛋白的分子功能研究

光周期是影响植物开花的重要环境信号，是决定植物分布范围的限制性因子之一；光周期钝化可以扩大作物种植区域，是作物驯化和改良的重要方面。了解日中性植物开花的分子调控机制可以为新型作物培育提供理论基础。CO/COL是长、短日照植物保守的光周期感受器，但日中性植物COL的功能仍知之甚少。本项目选取日中性植物番茄SlCOL1/3为研究对象，我们运用CRISPR技术和雌激素诱导表达体系分布构建了SlCOL1/3基因敲除突变体和SlCOL1/3条件诱导型过表达植物，初步结果显示SlCOL1/3不仅调控番茄的开花，还是果实/种子发育过程中重要的调控因子，而且还可能参与番茄对低温胁迫的响应。以上结果表明番茄SlCOL1/3不仅行使保守的调控开花基因的功能，还具有COL蛋白未有报道的全新分子功能；下一步我们将综合运用ChIP-Seq.、RNA-Seq.、IP-MS等分子遗传学手段对其作用机理进行深入研究。

Photoperiod is a significant environmental signal affecting flowering time, which is also one of limited factors that constrain the distribution of plants. Reducing sensitivity to day-length is a major selection trait during domestication and for the genetic improvement of crops. A thorough knowledge on the molecular mechanism of day-neutral plant flowering control would guide the cultivation of novel cultivar. CONSTANS/CONSTANS LIKE (CO/COL) proteins are conserved photoperiod sensors in both long-day plants and short-day plants, but the function of COLs in day-neutral plants remains unclear. For the purpose of further exploration of the regulatory network controlling flowering time and the molecular function of COL proteins in day-neutral plants, we select tomato SlCOL1 and SlCOL3 as target genes in the current study. We have generated SlCOL1/3 knockout mutants by CRISPR-Cas9 technology and SlCOL1/3 inducible overexpression plants with an estradiol-inducible expression system. The preliminary results indicated that the SlCOL1/3 function in flowering time regulation, controlling the fruit development and seed maturation, and may also involving in chilling stress responses. These results, as well as previous investigations, reveal not only a conserved function of SlCOL1/2 in regulating the expression of flowering time genes, but also other unreported potentials of COL proteins. We are going to investigate the detail molecular mechanism of SlCOL1/3 in plant development and stress responses with a combination of molecular genetic technologies such as IP-MS, ChIP-Seq., and RNA-Seq. in the current study.