Featured Research

from universities, journals, and other organizations

Uncapping the mystery behind the mechanism of cap removal from actin filaments

Date:
July 6, 2010
Source:
Public Library of Science
Summary:
In a new study, researchers present the X-ray crystal structures of the actin capping protein complexed with its inhibitors, V-1 and CARMIL, and demonstrate that the two regulators modulate the filament capping activity in very different manners.

In a new study, Shuichi Takeda at Nagoya University and colleagues present the X-ray crystal structures of the actin capping protein (CP) complexed with its inhibitors, V-1 and CARMIL, and demonstrate that the two regulators modulate the filament capping activity in very different manners.

These findings will be published in the online, open access journal PLoS Biology.

Dynamic rearrangement of actin cytoskeleton structure is fundamental to many cellular processes, such as neuronal development, immune response, and cancer metastasis. CP is a key regulator of actin, capping tightly to the dynamic end of the filament (the barbed end) to limit elongation. V-1 completely inhibits free CP from interacting with actin, whereas CARMIL acts on the barbed end-bound CP and uncaps the filament. However, the molecular mechanisms by which the two inhibitors modulate the capping activity remain poorly understood.

The new structures clearly indicate that while V-1 directly blocks the actin-binding site of CP preventing filament capping, CARMIL does not. So how does CARMIL uncap the filament? A clue was provided by a structural comparison analysis: CP has two stable domains that are continuously twisting relative to each other. Since CARMIL binds CP across the two domains like a chain, the authors concluded that CARMIL inhibits CP by suppressing the twisting movement required for tight-barbed end capping.

According to the authors, "CP is not a constitutively active inhibitor of barbed-end elongation; rather, the capping activity of CP is fine-tuned for the highly orchestrated assembly of the cellular actin machinery, and the conformational flexibility of CP provides the structural basis for the regulation." The new findings will pave the way for understanding the regulating mechanisms of actin dynamics that drives cell movement.


Story Source:

The above story is based on materials provided by Public Library of Science. Note: Materials may be edited for content and length.


Journal Reference:

  1. Takeda S, Minakata S, Koike R, Kawahata I, Narita A, et al. Two Distinct Mechanisms for Actin Capping Protein Regulation-Steric and Allosteric Inhibition. PLoS Biol, 2010; 8 (7): e1000416 DOI: 10.1371/journal.pbio.1000416

Cite This Page:

Public Library of Science. "Uncapping the mystery behind the mechanism of cap removal from actin filaments." ScienceDaily. ScienceDaily, 6 July 2010. <www.sciencedaily.com/releases/2010/07/100706171119.htm>.
Public Library of Science. (2010, July 6). Uncapping the mystery behind the mechanism of cap removal from actin filaments. ScienceDaily. Retrieved August 27, 2014 from www.sciencedaily.com/releases/2010/07/100706171119.htm
Public Library of Science. "Uncapping the mystery behind the mechanism of cap removal from actin filaments." ScienceDaily. www.sciencedaily.com/releases/2010/07/100706171119.htm (accessed August 27, 2014).

Share This




More Health & Medicine News

Wednesday, August 27, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Predicting Heart Transplant Rejection With a Blood Test

Predicting Heart Transplant Rejection With a Blood Test

Ivanhoe (Aug. 27, 2014) Now a new approach to rejection of donor organs could change the way doctors predict transplant rejection…without expensive, invasive procedures. Video provided by Ivanhoe
Powered by NewsLook.com
Better Braces That Vibrate

Better Braces That Vibrate

Ivanhoe (Aug. 27, 2014) The length of time you have to keep your braces on could be cut in half thanks to a new device that speeds up the process. Video provided by Ivanhoe
Powered by NewsLook.com
Smartphone App Tracks Your Heart Rate

Smartphone App Tracks Your Heart Rate

Ivanhoe (Aug. 27, 2014) A new app that can track your heart rate 24/7 is available for download in your app store and its convenience could save your life. Video provided by Ivanhoe
Powered by NewsLook.com
Stroke in Young Adults

Stroke in Young Adults

Ivanhoe (Aug. 27, 2014) A stroke can happen at any time and affect anyone regardless of age. This mother chose to give her son independence and continue to live a normal life after he had a stroke at 18 years old. Video provided by Ivanhoe
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins