拟南芥CLE14多肽抑制叶片衰老的机制研究

As an important developmental process of plants, leaf senescence affects many agronomic traits including yield and quality. The studies on mechanisms of leaf senescence regulation have important significance to implement manipulating leaf senescence in agriculture. Plant peptides act as important signals during plant development and responding to stresses. So far, the roles of plant peptides in regulating leaf senescence have not been reported. Our preliminary study showed that expression of CLE14, a member of CLE family genes that encode CLE peptides, is specifically up-regulated during leaf senescence; Both of two independent T-DNA insertion mutants lines display early senescence phenotypes; senescence of detached leaf treated with artificial CLE14 peptide was significantly delayed. Taken together, these results imply that CLE14 peptide is involved in regulating leaf senescence. In order to elucidate the biological function of CLE14 in leaf senscense, in this proposed study we will further analyze senescence phenotypes and expression of SAGs（senescence associate genes）in transgenic plants with specific overexpression in senescence stage as well as inducible overexpression of CLE14. Transcriptomic analysis will also be performed using these lines. In addition, we’ll perform the CLE14 artificial mature peptide treating assay to investigate interactions between CLE14 and known senescence-regulating genes and hormone. Results from this study will lay a foundation for further studies on the mechanisms of leaf senescence regulation by plant peptides. New ideas of manipulating leaf senescence in agricultural production could be generated through this study.

叶片衰老影响作物产量、品质等重要农艺性状。深入研究衰老的调控机理，对生产上实现衰老的合理控制进而提高产量具有重要意义。多肽作为信号分子参与了植物生长发育的分子调控，但它是否参与调控叶片衰老尚无报道。前期研究发现拟南芥CLE14多肽参与了叶片衰老调控：人工合成的CLE14多肽可使离体叶片衰老延缓；T-DNA插入位点不同的两个CLE14突变体株系都表现为叶片早衰；CLE14具有衰老特异性表达。本项目将通过对PSAG12::CLE14衰老时期特异过表达、诱导CLE14过表达转基因材料表型鉴定；CLE14多肽处理叶片及基因表达分析等手段明确CLE14的衰老调控功能；进一步通过转录组测序及多肽处理突变体，筛选CLE14调控的叶片衰老相关基因及激素路径，初步阐明CLE14参与叶片衰老调控的作用机制。研究结果将为阐明多肽调控叶片衰老的分子机制奠定基础，为探索生产上人工调控叶片衰老的可行技术提供新的思路。

叶片衰老影响作物产量、品质等重要农艺性状。深入研究衰老的调控机理，对生产上实现.衰老的合理控制进而提高产量具有重要意义。多肽作为信号分子参与了植物生长发育的分子调.控，但它是否参与调控叶片衰老尚无报道。前期研究发现拟南芥CLE14多肽参与了叶片衰老调.控：人工合成的CLE14多肽可使离体叶片衰老延缓；T-DNA插入位点不同的两个CLE14突变体株.系都表现为叶片早衰；CLE14具有衰老特异性表达。本项目将通过对PSAG12::CLE14衰老时期特.异过表达、诱导CLE14过表达转基因材料表型鉴定；CLE14多肽处理叶片及基因表达分析等手段.明确CLE14的衰老调控功能；进一步通过转录组测序及多肽处理突变体，筛选CLE14调控的叶片.衰老相关基因及激素路径，初步阐明CLE14参与叶片衰老调控的作用机制。研究结果将为阐明.多肽调控叶片衰老的分子机制奠定基础，为探索生产上人工调控叶片衰老的可行技术提供新的.思路