INTRON ORIGINS EXAMINED USING ORGANELLE DERIVED GENES

这项研究的长期目标是了解内含子何时以及如何出现以及它们的进化历史。 一种假说认为，许多现存的内含子是古代内含子的遗迹，在古代生物中用于重组小的外显子模块，从而产生更大的基因。 这种内含子早期假说预测相邻的内含子相对于阅读框架将处于相同的相位。 我将分析一个包含内含子的基因数据库，这些内含子被认为是最近出现的（从细胞器转移到细胞核的基因）。 如果这些基因具有对称的相位相关性，则表明内含子可能由于外显子改组以外的原因而显示出这些相关性，并且这种预测不能用于支持古老的外显子改组假说。 古老的内含子改组假说也预测内含子将位于紧凑的3D蛋白质模块之间。 我将在上述数据库中查找这些位置的内含子。 如果内含子偏好非改组基因中的这些模块边界区域，则不能使用模块边界预测来支持内含子早期假说。 最后，我将比较非改组数据库中的内含子密度与其他核基因。 如果这两个数据集中的内含子密度以谱系特异性的方式彼此镜像，则这表明原始核基因具有很少的内含子。 由于大多数人类基因包含许多内含子，了解内含子如何产生以及它们的进化历史和用途对健康的潜在好处是巨大的。 许多人类疾病都有内含子相关的原因。了解内含子如何传播可能会导致新的基因治疗技术。 鉴于内含子的基本性质，了解它们将大大增加对我们自己的了解。

The long term objective of this research is to understand when and how introns arose and what their evolutionary history has been. One hypothesis proposes that many extant introns are the vestiges of ancient introns used in ancient organisms to shuffle small exonic modules and thereby create larger genes. This introns-early hypothesis predicts that adjacent introns will be in the same phases relative to the reading frame. I will analyze a database of genes containing introns accepted to have arisen recently (genes transferred from organelles to the nucleus). If these genes have symmetric phase correlations it would suggest that introns could show these correlations for reasons other than exon shuffling and that this prediction can not be used to support the ancient exon shuffling hypothesis. The ancient intron shuffling hypothesis also predicts that introns will lie between compact 3D protein modules. I will look in the above database for introns at these positions. If introns prefer these module boundary regions in the non-shuffled genes the module boundary prediction can not be used to support the introns-early hypothesis. Lastly, I will compare intron densities in the non- shuffled database with other nuclear genes. If the intron densities in these two datasets mirror each other in a lineage specific manner this suggests that the original nuclear genes had few introns. Since most human genes contain many introns the potential health benefits of understanding how introns arose and what their evolutionary history and utility have been are enormous. Numerous human diseases have intron-related causes. Understanding how introns propagate could lead to novel gene therapy techniques. Given the elementary nature of introns, understanding them will greatly increase understanding of ourselves.