Navigation Links
Constant overlap
Date:8/5/2010

During cell division, microtubules emanating from each of the spindle poles meet and overlap in the spindle's mid zone. Scientists at the European Molecular Biology Laboratory (EMBL) in Heidelberg, Germany, have uncovered the molecular mechanism that determines the extent of this overlap. In a study published today in Cell, they were able to reconstruct such anti-parallel microtubule overlaps in vitro, and identify two proteins which are sufficient to control the formation and size of this important spindle feature.

Thomas Surrey and his group at EMBL found that one protein, PRC1, bundles together microtubules coming from opposite ends of the cell, attaching them to each other. It then recruits a second protein, a molecular motor from the kinesin-4 subfamily, increasing its concentration in the spindle mid zone. This motor walks along the overlapping microtubules like an officer on patrol, until it reaches one of the ends. When enough kinesin-4 molecules reach the end of the overlap, they inhibit the growth of microtubules there, thus keeping the overlap size constant without affecting microtubules elsewhere in the cell.

The spindle mid zone plays an important role not only in helping to align the chromosomes in metaphase, but also in the final stages of cell division, when it drives the physical separation of the two daughter-cells. But between these two stages, the two ends of the spindle must move away from each other, to drag half the genetic material to each side of the dividing cell. At this point, if PRC1 and kinesin-4 had stopped microtubule growth permanently in the central part of the spindle, the overlap would become smaller and smaller, until eventually the spindle itself would collapse, jeopardising cell division. But Surrey and colleagues found that PRC1 and kinesin-4 control the overlap size in an adaptive manner. As the spindle stretches and the overlap between microtubules becomes smaller, the scientists posit, the inhibitory effect of kinesin-4 diminishes, allowing the microtubule ends to grow.

"Our findings show how molecules millionths of millimetres small can control the size of a structure about a thousand times larger than themselves," Surrey concludes: "they help us to understand the fundamentals of cell division."


'/>"/>

Contact: Lena Raditsch
lena.raditsch@embl.de
European Molecular Biology Laboratory
Source:Eurekalert

Related biology news :

1. Finding the constant in bacterial communication
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:11/24/2016)... , Nov. 23, 2016 Cercacor today ... athletes and their trainers non-invasively measure hemoglobin, ... Pulse Rate, and Respiration Rate in approximately 30 seconds. ... users easy and immediate access to key data about ... of a training regimen. Hemoglobin carries ...
(Date:11/17/2016)... LONDON , Nov. 17, 2016 Global Market ... and Public Biobanks (Disease-Based Banks, Population-Based Banks and Academics) market ... Geographical analysis for Private Biobanks shows the highest Compounded Annual ... Asia-Pacific region during the analysis period 2014-2020. ... a CAGR of 9.95% followed by Europe ...
(Date:11/14/2016)... Technology, Inc. ("xG" or the "Company") (Nasdaq: XGTI, XGTIW), ... in challenging operating environments, announced its results for the ... a conference call to discuss these results on November ... Key Recent Accomplishments ... acquire Vislink Communication Systems. The purchase is expected to ...
Breaking Biology News(10 mins):
(Date:12/2/2016)... DC (PRWEB) , ... December ... ... Consortiumâ„¢ (ETC), a consortium of pharmaceutical and biotechnology companies dedicated to collaboratively ... seeking companies interested in supplying a vendor-supported, portable online UHPLC, with robust, ...
(Date:12/2/2016)... The immunohistochemistry (IHC) market is projected ... of 7.3% during the forecast period of 2016 to 2021 dominated ... accounted for the largest share of immunohistochemistry (IHC) market, by end ... , , ... market spread across 225 pages, profiling 10 companies and supported with ...
(Date:11/30/2016)... announced the appointment of Joshua F. Coleman , M.D., ... Coleman will oversee clinical content development and curation of scientific ... suite empowers molecular pathologists with a seamless workflow for the ... quality control through reporting. ... , , Prior ...
(Date:11/30/2016)... , Nov. 30, 2016 Biotest Pharmaceuticals Corporation ... pleased to announce the addition of its newest plasma ... Kearney, Nebraska . The 15,200 square foot state-of-the-art ... 29th, 2016 and brings the total number of BPC,s ... Ileana Carlisle , BPC,s Chief Executive Officer said "We ...
Breaking Biology Technology: