目的 长链非编码RNA(Long non-coding RNA，lncRNA)长度大于200 nt，一般不具有编码蛋白质功能。探究低温下lncRNA对邻近SAUR基因表达的影响，以期为研究水稻种子低温萌发的能力提供理论依据。方法 lncRNA SVR由华南农业大学国家植物航天育种工程技术研究中心前期研究筛选，可以响应低温胁迫，通过生物信息学方法分析lncRNA SVR的二级结构并寻找lncRNA SVR内部的冷胁迫基序，通过qRT-PCR分析lncRNA SVR和SAUR基因的表达特性。结果 lncRNA SVR序列中存在高度相似的冷胁迫响应基序，且在茎环连接处。表达特性分析表明，在种子萌发过程中低温胁迫会持续降低lncRNA SVR的表达，邻近的多个SAUR基因在低温胁迫下的表达量明显高于在常温下的表达量，表明lncRNA SVR的邻近SAUR基因一定程度上能够和lncRNA SVR一样响应低温胁迫。表达相关性分析表明，在低温萌发中lncRNA SVR与这些SAUR基因的表达均呈负相关关系，lncRNA SVR与OsSAUR55的表达呈显著负相关关系。进一步分析种子低温萌发中SAUR基因在lncRNA SVR敲除系中的表达情况，结果表明，在敲除系中，lncRNA SVR的下降幅度低于其在野生型中的下降幅度，OsSAUR41、OsSAUR53、OsSAUR54、OsSAUR55表达量的上升幅度均显著低于其在野生型中的上升幅度。结论 lncRNA SVR可能负调控OsSAUR55的表达，进而响应低温胁迫。
Objective Long non-coding RNA (lncRNA) is longer than 200 nt and generally does not code proteins. To explore the effect of lncRNA on the expression of neighbouring SAUR genes under low temperature, and provide a theoretical basis for studying the ability of rice seeds to germinate at low temperature. Method lncRNA SVR was investigated in response to cold stress in previous research of National Engineering Research Center of Plant Space Breeding, South China Agricultural University. The secondary structure of lncRNA SVR was analysed by bioinformatics, and the cold stress motifs within lncRNA SVR was searched. The expression characteristics of lncRNA SVR and SAUR genes were analysed by qRT-PCR.Result In this study, highly similar cold stress response motifs were found in the sequence of lncRNA SVR and at the stem-loop junction. Expression characterization showed that cold stress during seed germination continuously decreased the expression of lncRNA SVR, and the expression of some neighbouring SAUR genes was significantly higher under cold stress than that at room temperature, indicating that the neighbouring SAUR genes could respond to cold stress to some extent as well as lncRNA SVR. Expression correlation analysis showed that the expression relationship between lncRNA SVR and these SAUR genes in low temperature germination were all negatively correlated, and the expression of lncRNA SVR and OsSAUR55 showed a significant negative correlation. Further analysis of SAUR gene expression in low temperature seed germination in the lncRNA SVR knockout lines showed that the decrease of lncRNA SVR in the knockout lines was lower than that in the wild type, and the increase in expression of OsSAUR41, OsSAUR53, OsSAUR54 and OsSAUR55 was significantly lower than that in the wild type.Conclusion lncRNA SVR is able to negatively regulate the expression of OsSAUR55, further respond to low temperature stress.