Mapping the Cell's Nucleus

摘要

Biologists are learning that the nuclear matrix--a mostly unexplored mix of insoluble molecules--may hold keys to how genes turn off and on and how they code for working proteins. When James Davie started investigating the inner workings of the chromosomes, which carry the cell's genetic information, in the mid-1970s, he tossed some important clues down the drain. Davie, a biochemist at the University of Manitoba in Winnipeg, was studying chromatin--the DN A and protein mixture that forms the chromosomes. In the course of that work, he would extract most of the DN A and soluble proteins from the nucleus, where the chromosomes reside, and keep that material. Then, following traditional practice, he poured the insoluble fraction that remained down the sink. "We ignored that fraction for the longest time because we figured it's just nuclear debris," he recalls. "That was the feeling of the day."