植物对热胁迫的响应机制是胁迫生理研究的热点科学问题。有关草坪草耐热的分子机理尚少见报导。MicroRNAs因其在基因转录后水平调节基因表达的重要作用而成为生命科学以及农业领域的研究热点，其中microRNA319 (miR319)基因被发现参与植物对不同逆境胁迫的反应。以冷季型草坪草-多年生黑麦草为材料，将来源于水稻的miR319基因转入，成功获得转基因植株，经测试转基因植株的耐热性显著提高。计划设置短期和长期的热胁迫试验，采用转录组测序技术筛选转基因植株与非选转基因植株差异表达的基因。通过数据关联分析、代谢通路基因的富集分析，转基因验证，结合从生理水平分析抗逆指标与生物信息数据的关联性，旨在揭示草坪草耐热的分子机理。所获得的转基因材料为进一步通过遗传育种提高草坪草/牧草的耐热性提供了很好的种质材料。试验具有理论探讨的意义也有较高的应用价值。

The mechanism of plant heat stress responses is a hot research topic in stress physiology. So far the researches on the molecular mechanism of turfgrass heat tolerance are few. Due to their vital roles in post-transcriptional regulation of gene expression, microRNAs have gained great attention in life science and agricultural research. One microRNA gene, microRNA319 (miR319) was found to be involved in plant responses to various abiotic stresses. Here we used a cool-season turfgrass, perennial ryegrass as the plant material, and introduced a rice miR319 gene into the genome of the grass. Transgenic perennial ryegrass showed markedly enhanced heat stress tolerance compared to the wild type. The project will design an experiment with both short and long period high temperature treatments, and will use RNA-Seq technique to screen the genes that show significantly different expression between the transcriptome of the miR319 transgenic perennial ryegrass and non-transgenic plants under heat stress. By combining data association analysis, KEGG metabolic pathway gene enrichment analyses, and gene function confirmation via transgenic analysis with the physiological parameters measured, the project will be able to expound the molecular mechanism of how the heat tolerance is improved in perennial ryegrass by miR319 overexpression. The transgenic plants produced during the project can be useful germplasm materials for breeding heat-tolerant turfgrass/forage. And the project has both theoretical significance and good practical value.