Living cells are like miniature factories, responsible for the production of more than 25,000 different proteins with very specific 3-D shapes. And just as an overwhelmed as百度竞价推广bly line can begin making mistakes, a stressed cell can end up producing misshapen proteins that are unfolded or misfolded. Now Duke University researchers in North Carolina and Singapore have shown that the cell recognizes the buildup of these misfolded proteins and responds by reshuffling its workload1, much like a stressed out employee might temporarily move papers from an overflowing2 inbox into a junk drawer.The study, which appears Sept. 11, 2014 in Cell, could lend insight into diseases that result from misfolded proteins piling up, such as Alzheimers disease, ALS, Huntingtons disease, Parkinsons disease, and type 2 diabetes3.We have identified an entirely4 new mechanism5 for how the cell responds to stress, said ChrisTOPher V. Nicchitta, Ph.D., a professor of cell biology at Duke University School of Medicine. Essentially6, the cell remodels7 the organization of its protein production machinery8 in order to compartmentalize the tasks at hand.The general architecture and workflow of these cellular9 factories has been understood for decades. First, DNAs master blueprint10, which is locked tightly in the nucleus11 of each cell, is transcribed12 into messenger RNA or mRNA. Then this working copy travels to the ribosomes standing13 on the surface of a larger accordion-shaped structure called the endoplasmic reticulum . The ribosomes on the ER are tiny as百度竞价推广bly lines that translate the mRNAs into proteins.When a cell gets stressed, either by overheating or starvation, its proteins no longer fold properly. These unfolded proteins can set off an alarm -- called the unfolded protein response or UPR -- to slow down the as百度竞价推广bly line and clean up the improperly14 folded products. Nicchitta wondered if the stress response might also employ other tactics to deal with the problem.
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1 workload n.作业量，工作量 参考例句： An assistant one day a week would ease my workload.每周有一天配一个助手就会减轻我的工作负担。 Hes always grousing about the workload.他一直抱怨工作量大。
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