核仁小分子RNA是一类广泛存在于真核生物中的非编码RNA。因其在介导核酸修饰加工方面的重要性及其不断被发现的新功能使该类分子成为近年来RNA研究中的重要对象之一。虽然在动物中人们发现它们可以不同机制参与调节多种重要生命过程，但单个核仁小分子RNA对高等植物生长发育的调控作用尚未见报道。本项目基于实验室前期对拟南芥全基因组核仁小分子RNA的注释与分析，以一个很可能参与拟南芥顶端分生组织发育调控的核仁小分子RNA（HIT2）为对象来研究其生物学功能与作用机理。我们拟结合RNA研究中的新技术与方法，通过HIT2在分生组织发育中的功能分析、HIT2自身转录调控分析、HIT2特征序列元件与功能分析以及HIT2功能效应与关键下游作用因子鉴定四个方面揭示其植物体内的作用机制。我们的目标是揭示关键核仁小分子RNA在植物生长发育中介导的新遗传信息传递网络，为主要农作物与经济作物的培育提供重要的理论基础。

Small nucleolar RNAs (snoRNA) represent a class of noncoding RNAs that are widely distributed in eukaryotes. Due to their important functions in the modification and processing of other RNAs, as well as their gradually exploited new functions, they became one of the research hotspots in RNA research. snoRNAs in animals have been found to regulate multiple vital biological processes, however, the functional link of individual snoRNA to plant growth and development remains to be obscure. Based on our previous study on the identification and characterization of Arabidopsis snoRNAs on a genome-wide scale, we screened and identified a key snoRNA, designated HIT2, that is most likely essential for the development of apical meristem in Arabidopsis. Combined with the advanced technologies and methods in RNA research, we will investigate the molecular mechanism of HIT2 regulating meristem development in Arabidopsis through the following four aspects: functional study of HIT2 in apical meristem development, the transcriptional regulation of HIT2 in vivo, structure to function dissection of HIT2, and the identification of HIT2 interacting proteins and its downstream targets. We aim to uncover snoRNA mediated new regulatory network in control of plant growth and development in the model plant Arabidopsis, which will provide the theoretical basis for crop genetic improvement.