Detailed mapping of the sites of interaction of polypyrimidine tract binding protein with its RNA targets: viral and cellular IRESs and pre-mRNAs.

聚嘧啶束结合蛋白与其 RNA 靶标（病毒和细胞 IRES 和前 mRNA）相互作用位点的详细图谱。

• 批准号: BB/E004857/1
• 负责人: Richard Jackson
• 金额: $ 36.48万
• 依托单位: University of Cambridge
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2007
• 资助国家: 英国
• 起止时间: 2007 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FE004857%2F1
• 关键词: Detailed; mapping; sites; interaction; polypyrimidine

The strong physical, behavioural, and mental similarity of identical twins shows that it is our genetic material that largely specifies what we are. This genetic material is our DNA, which can be regarded as an exceedingly long 'tape' (e.g. an enormous video tape) with some 3 billion bits of information, coding for the numerous different types of protein which carry out most of our bodily functions. The DNA can be thought of as the 'master tape', an archive of thousands of normal length videos joined together. The process of decoding this information in the DNA involves first making a working copy of one of these videotapes in the archive. In fact the information in this initial copy is segmented, with the meaningful segments interspersed with meaningless sections. Consequently, the meaningful segments in this initial copy need to be cut out and spliced together, much as cine films were created by splicing in the pre-electronic era. In many cases, this splicing can occur in slightly different ways, with some meaningful segments excluded in some cells or some circumstances, but included in other cells/circumstances. Thus the initial copy of the archived 'video' can give rise to more than one variant of the final playable video. A protein known as polypyrimidine tract binding protein (PTB) exerts a strong influence on the alternative splicing, causing the inclusion of some meaningful segments and the exclusion of others. After the video has been spliced together it is decoded by a small particle known as a ribosome, which essentially carries out an analogous function to that of a video recorder (VCR) as it decodes the information as pictures. The 'biological videos' are similar to real videos in so far as the part of the tape with the pictorial information is preceded by a short leader length that has no information. In most cases our biological VCR (the ribosome) finds the point where the true information starts by searching or scanning in fast-forward mode through the whole meaningless leader. However, with some such videos the biological VCR is able to go straight to the starting point where the meaningful pictorial information begins without searching through the meaningless leader section, and in many such cases PTB is necessary for the direct location of the start position by the biological VCR. The aim of this project is to find out how PTB (a) causes the biological VCR to locate these starting sites without a need for searching through the tape from the very start, and (b) can influence the exact pattern in which the different meaningful segments are spliced together to give the finished video tape.

同卵双胞胎在身体、行为和精神上的强烈相似性表明，我们的遗传物质在很大程度上决定了我们是什么样的人。这种遗传物质就是我们的DNA，它可以被看作是一条极长的“磁带”（例如，一条巨大的录像带），里面有大约30亿比特的信息，编码着许多不同类型的蛋白质，这些蛋白质执行着我们大部分的身体功能。DNA可以被认为是“母带”，一个由数千个正常长度的视频连接在一起的档案。解码DNA信息的过程包括首先制作一份档案中这些录像带的工作副本。事实上，这个初始副本中的信息是分段的，有意义的部分穿插着无意义的部分。因此，在这个初始拷贝中，有意义的片段需要被剪切并拼接在一起，就像在前电子时代通过拼接创造电影一样。在许多情况下，这种剪接可以以略微不同的方式发生，一些有意义的片段在某些细胞或某些情况下被排除在外，但在其他细胞/情况下被包括在内。因此，存档“视频”的初始副本可以产生最终可播放视频的多个变体。一种被称为聚嘧啶束结合蛋白（PTB）的蛋白质对选择性剪接有很强的影响，导致一些有意义的片段被包含而另一些片段被排除。在视频被拼接在一起后，它被一种被称为核糖体的小粒子解码，核糖体本质上执行与录像机（VCR）类似的功能，将信息解码为图像。“生物视频”与真正的视频相似，因为在带有图像信息的磁带部分之前有一段没有信息的短长度。在大多数情况下，我们的生物VCR（核糖体）通过搜索或扫描整个无意义的前导，以快进模式找到真正信息开始的点。然而，在一些这样的视频中，生物录像机能够直接到达有意义的图像信息开始的起点，而不需要搜索无意义的领导部分，在许多这样的情况下，PTB对于生物录像机直接定位起始位置是必要的。本项目的目的是找出PTB (a)如何使生物录像机在不需要从头开始搜索磁带的情况下定位这些起始位置，以及(b)如何影响不同有意义的片段拼接在一起以形成最终录像带的确切模式。