注册 登录  
 加关注
   显示下一条  |  关闭
温馨提示!由于新浪微博认证机制调整,您的新浪微博帐号绑定已过期,请重新绑定!立即重新绑定新浪微博》  |  关闭

wangyufeng的博客

祝愿BB 健康开心快乐每一天

 
 
 

日志

 
 

植物冻害机理研究最新进展:Novel Mechanism Protects Plants Against Freezing  

2011-04-30 13:16:04|  分类: 抗性基因 |  标签: |举报 |字号 订阅

  下载LOFTER 我的照片书  |
        植物冻害Plant frost)属于非侵染性病害,是由于气候因素引起的病害。冻害形成的机理目前认为是植物细胞膜的位相变化所引起的,即在低温胁迫下细胞膜的内在蛋白质变性,使主动运输系统钝化而造成的。来自Michigan大学的最新研究结果对于了解植物冻害以及干旱胁迫提供了新的思路。

Novel Mechanism Protects Plants Against Freezing; Insights Could Add to Understanding of Drought Tolerance Also

ScienceDaily (Aug. 27, 2010) — New ground broken by Michigan State University biochemists helps explain how plants protect themselves from freezing temperatures and could lead to discoveries related to plant tolerance for drought and other extreme conditions.
植物冻害机理研究最新进展:Novel Mechanism Protects Plants Against Freezing - 喜欢吃桃子 - wangyufeng的博客
This shows the effects of five days of freezing and then thawing on wild-type, freezing-resistant Arabidopsis thaliana, left, and mutant, freeze-sensitive Arabidopsis at right. (Credit: Eric Moellering, MSU)

"This brings together two classic problems in plant biology," said Christoph Benning, MSU professor of biochemistry and molecular biology. "One is that plants protect themselves against freezing and that scientists long thought it had something to do with cell membranes, but didn't know exactly how.

"The other is the search for the gene for an enigmatic enzyme of plant lipid metabolism in the chloroplasts," in other words, how lipids, which are membrane building blocks, are made for the plant cell organelles responsible for converting solar energy into chemical energy by photosynthesis.

In an article published online in the journal Science, Benning and his then-doctoral degree candidate Eric Moellering and technical assistant Bagyalakshmi Muthan describe how a particular gene leads to the formation of a lipid that protects chloroplast and plant cell membranes from freeze damage by a novel mechanism in Arabidopsis thaliana, common mustard weed. Working on his dissertation project under Benning, Moellering identified a mutant strain of Arabidopsis that can't manufacture the lipid and linked this biochemical defect to work done by others who originally described the role of the gene in freeze tolerance, but did not find the mechanism.

"One of the big problems in freezing tolerance or general stress in plants is that some species are better at surviving stress than others," Moellering said. "We are only beginning to understand the mechanisms that allow some plants to survive while others are sensitive."

There is no single mechanism involved in plant freezing tolerance, Moellering added, so he can't say that his findings will lead any time soon to genetic breakthroughs making citrus or other freezing-intolerant plants able to thrive in northern climates. But it does add to our understanding of how plants survive temperature extremes.

Much plant damage in freezing temperatures is due to cell dehydration, in which water is drawn out as it crystallizes and the organelle or cell membrane shrivels as liquid volume drops. Lipids in the membranes of tolerant plants are removed and converted to oil that accumulates in droplets, the researchers said, retaining membrane integrity, keeping membranes from fusing with one another and conserving the energy by storing oil droplets. With rising concern globally about water supplies and climate change, scientists see additional reasons to understand the ways hardy plants survive.

The research, funded by the U.S. Department of Energy Office of Science Basic Energy Sciences and the Michigan Agricultural Experiment Station, also leads to speculation that freezing itself can prompt cell proteins directly to change the composition of the membrane, without activation by gradual acclimation. That has been a major focus in the plant freezing tolerance field, the researchers said.

"This opens a huge door now for people to do this kind of research, and to redirect researchers," Benning said. "There are lots of them out there trying to understand cold, salt and drought tolerance in plants, and we've given them a new idea about how they can approach this problem mechanistically."

 Journal Reference:Eric R. Moellering, Bagyalakshmi Muthan, and Christoph Benning. Freezing Tolerance in Plants Requires Lipid Remodeling at the Outer Chloroplast Membrane. Science, 2010; DOI: 10.1126/science.1191803

More information pls links to: Michigan State University (2010, August 27). Novel mechanism protects plants against freezing; Insights could add to understanding of drought tolerance also. ScienceDaily. Retrieved April 30, 2011, from http://www.sciencedaily.com? /releases/2010/08/100826141213.htm

  评论这张
 
阅读(991)| 评论(0)
推荐 转载

历史上的今天

在LOFTER的更多文章

评论

<#--最新日志,群博日志--> <#--推荐日志--> <#--引用记录--> <#--博主推荐--> <#--随机阅读--> <#--首页推荐--> <#--历史上的今天--> <#--被推荐日志--> <#--上一篇,下一篇--> <#-- 热度 --> <#-- 网易新闻广告 --> <#--右边模块结构--> <#--评论模块结构--> <#--引用模块结构--> <#--博主发起的投票-->
 
 
 
 
 
 
 
 
 
 
 
 
 
 

页脚

网易公司版权所有 ©1997-2017