Gene Regulation in Lens Regeneration

描述（由申请人提供）：透镜再生是一种仅限于某些有尾目动物的独特现象。在晶状体切除术后，新的透镜通过背侧虹膜色素上皮细胞（佩奇）的转分化形成。腹侧虹膜对该过程没有贡献。然而，有趣的是，当蝾螈腹侧虹膜或任何动物（包括老年人）的色素上皮细胞（PE）被长期培养时，它们会转分化为透镜。换句话说，许多物种的佩奇都有再生透镜的能力，但在体内，这种能力只有某些蝾螈才有。这个提议的最初假设是，蝾螈眼睛的背侧虹膜和腹侧虹膜中一定有特定的基因表达，这可以帮助我们识别可能调节和诱导透镜再生的因素。在过去的几年里，我们已经研究了几个基因的表达模式，我们已经确定了几个很好的候选人这样的作用。这些基因是pax-6、six-3、FGFR-1和prox-1。然后，我们提出，这些基因可用于抑制腹侧佩奇，这缺乏转分化为透镜的能力，试图诱导透镜再生。我们已经成功地使用了两种不同的协议。在其中一个中，腹侧佩奇用6 -3转染并用视黄酸处理，而在另一个腹侧虹膜中用BMP通路的可溶性抑制剂处理。这些是诱导的第一个案例，我们现在想利用这些知识来了解其他动物透镜再生的限制并诱导它。在第一次成功地从腹侧虹膜诱导透镜再生之后，我们现在建议检查参与治疗诱导的分子途径，并在其他通常不能诱导的动物中诱导透镜再生。透镜再生的过程，比如蝾螈和老鼠。这可能会导致使用已建立的动物模型进行实验，最终可以更有效地用于临床应用。

DESCRIPTION (provided by applicant): Lens regeneration is a unique phenomenon restricted only to some urodeles. Upon lentectomy the new lens is formed by the transdifferentiation of the dorsal iris pigment epithelial cells (PECs). The ventral iris does not contribute to the process. What is interesting, however, is that when cells, from the ventral iris of the newt or from the pigmented epithelium (PE) of any animal including old humans, are placed in culture for long periods of time, they transdifferentiate to lens. In other words, PECs from many species are capable for lens regeneration, but in vivo, this capacity is unique to some newts only. The original hypothesis of this proposal was that there must be specific genes expressed in the dorsal versus the ventral iris of the newt eye that could help us identify factors that might regulate and induce lens regeneration. In previous years, we have studied expression patterns of several genes and we have identified several good candidates for such role. These genes were pax-6, six-3, FGFR-1 and prox-1. We then proposed that these genes could be used to transfect ventral PECs, which lack the ability to transdifferentiate to lens, in an attempt to induce lens regeneration. We have been successful with two different protocols. In one of them, ventral PECs were transfected with six-3 and treated with retinoic acid and in the other ventral irises were treated with a soluble inhibitor of the BMP pathway. These are the first cases of induction and we now would like to utilize this knowledge to understand the restriction of lens regeneration in other animals and to induce it. Having succeeded for the first time in inducing lens regeneration from the ventral iris, we now propose to examine the molecular pathways that are involved in the induction due to the treatments and to induce lens regeneration in other animals that are normally incompetent of lens regeneration, such as in the axolotl and mice. This might lead to experimentation with established animal models, which eventually can be used more efficiently in clinical applications.