Stem cell news: LSD1使ESC基因“退役” / StemCells启动干细胞治疗AMD临床试验
2012-02-03 01:30:00   来源：干细胞之家 作者：kittybruce    

Whitehead研究所最近Nature文章发现去甲基化酶LSD1在ESC分化中使多能性基因的增强子失去作用，从而关闭多能性基因的表达。

另一则是美国StemCells公司得到FDA批准开始干细胞治疗AMD临床试验，与先进细胞公司不同的是，StemCells公司用的是来自人的神经干细胞HuCNS-SC（来自胎儿？），此外他们把目标定位在保存视网膜光感细胞功能方面，而不是再生出新的光感细胞。


InvestorStemcell.com
Chaos in the cell’s command center

Posted by iCELL News, on 02nd February 2012, in Stem Cell Research.

Whitehead Institute for Biomedical Research

CAMBRIDGE, Mass. – A defective operating system is never a good thing.

Like computers, our cells depend on operating systems to drive normal functions. Gene expression programs comprise the software code our cells rely on, with each cell type controlled by its own program. Corrupted programs can trigger disease.

Cellular operating systems can be corrupted by viruses, mutations, or malfunctions that occur as cells change from one type to another. Unlike computers that can use one operating system for their entire existence, differentiating cells need to switch operating systems as they mature?—from stem cell to, for example, nerve or muscle cell. In simple terms, differentiation requires two key steps: the genes active in the initial operating system must be deactivated; and the genes of the new cellular operating system must be turned on. If the switch is not flawless, a transitioning cell may die or be driven by a disease-causing program.

New research from Whitehead Institute scientists reveals the critical role one enzyme, lysine-specific demethylase 1 (LSD1), plays as embryonic stem cells differentiate into other cell types. Their research is published online this week in the journal Nature.

LSD1 was known to be critical to development, but little was known about the key role it plays during differentiation, when operating systems are switched.

“We knew that cells express a new set of genes when the operating switch occurs,” says Steve Bilodeau, one of the Nature paper’s authors and a postdoctoral researcher in the lab of Whitehead Member Richard Young. “But this study shows it is also essential to shut off genes that were active in the prior cell state. If you don’t, the new cell is corrupted.”

By investigating gene silencing during cell state transitions, Bilodeau and Warren Whyte, a Young lab graduate student and co-author of the Nature paper, redefined LSD1′s role and described a previously unknown mechanism for silencing genes.