miRT

MicroRNAs (miRNAs) are small endogeneous non-coding RNAs of about 22nt length. These short RNAs regulate the expression of mRNAs by hybridizing with their 3'-UTRs or by translational repression. They have been shown to take crucial roles in many biological processes. Many of the current studies are focused over how mature miRNAs regulate mRNAs, even though very limited knowledge is there about their transcriptional loci. Primary miRNAs (pri-miRs) are first transcribed from the DNA, followed by the formation of precursor miRNA (pre-miR) by endonucleases activity, which finally produces mature miRNAs. Unfortunately, the identification of the loci of pri-miRs, and the associated information about transcription start sites (TSSs) and promoters is still in progress. There are reported results concerning the TSSs of about 40% of the total mature miRNAs hitherto explored in human. This limited information, presented as the miRT database, is useful for further study on the regulation of miRNAs.

微小RNA（MicroRNAs, miRNAs）是一类长度约为22个核苷酸的小型内源非编码RNA。这类短链RNA可通过与靶信使RNA（mRNA）的3'非翻译区（3'-UTRs）结合或介导翻译抑制，调控信使RNA的表达。现有研究证实，它们在诸多生物学过程中发挥关键作用。当前多数研究聚焦于成熟miRNA对信使RNA的调控机制，而人们对其转录位点的认知仍极为有限。初级微小RNA（pri-miRs）首先由DNA转录生成，随后经核酸内切酶催化加工为前体微小RNA（pre-miR），最终裂解产生成熟miRNA。遗憾的是，初级微小RNA的转录位点、转录起始位点（TSSs）及启动子等相关信息的鉴定工作仍在进行中。截至目前，在已被研究的人类成熟miRNA中，仅约40%的转录起始位点有相关报道。上述有限信息以miRT数据库的形式整理呈现，可为后续miRNA调控机制的深入研究提供参考依据。

搜集汇总

背景与挑战

背景概述

miRT是一个专注于人类microRNAs转录起始位点（TSSs）的数据库，收录了已验证的TSSs信息，目前覆盖约40%的人类成熟miRNA。该数据库旨在解决对microRNAs转录位点（如pri-miRs的TSSs和启动子）知识有限的问题，为研究microRNAs的调控机制提供关键数据支持。