Featured Research

from universities, journals, and other organizations

Key Protein Can Help Cells Or Cause Cancer

Date:
July 11, 2009
Source:
Purdue University
Summary:
Scientist have discovered a key process in cell growth that can lead to the formation of tumors. They found that an overabundance of the polo-like kinase 1, or Plk1, molecule during cell growth, as well as a shortage of the p53 molecule, will lead to tumor formation.

A Purdue University scientist has discovered a key process in cell growth that can lead to the formation of tumors.

Related Articles


Xiaoqi Liu, an assistant professor of biochemistry, found that an overabundance of the polo-like kinase 1, or Plk1, molecule during cell growth, as well as a shortage of the p53 molecule, will lead to tumor formation. Studies in Liu's laboratory showed that the Plk1 molecule indirectly attacks p53 in a process called ubiquitination.

"This provides the mechanism for how p53 loses its function in cancer cells," said Liu. "If we understand how the cancer forms, then we can create a more useful therapeutic approach to treating that cancer."

During cell growth, Plk1 uses its protein kinase activity called phosphorylation, which consists of adding a phosphate group to a protein called Topors. Topors binds itself to p53 molecules during the ubiquitination process. Phosphorylation is basically an instruction from Plk1 to increase its ubiquitination activity, which kills p53 molecules.

Liu said p53 could be thought of as a protective force. When Topors kills off that force, Plk1 becomes stronger, allowing the cells to become cancerous.

"We're trying to understand how p53 is regulated. We want to keep p53 as normal as possible," Liu said. "In about 50 percent of cancers, p53 had lost its function, and there was too much Plk1. Since Plk1 is overexpressed in cancers, it is a cancer therapy target."

Topors can also carry out a function called sumoylation, in which Topors binds to p53 molecules and creates more p53. Liu was able to force cells in his lab to go through the ubiquitination or sumoylation process to show how p53 molecules were affected.

Liu said it is unknown why the Plk1 molecule chooses to initiate ubiquitination over sumoylation.

Researchers from Sichuan University in China and faculty in the Department of Basic Medical Sciences at Purdue collaborated with Liu on the research. The work was funded through a Howard Temin Award from the National Institutes of Health.

Liu said the next step in the research is to test different Plk1 inhibitors to see how they affect the phosphorylation process.


Story Source:

The above story is based on materials provided by Purdue University. Note: Materials may be edited for content and length.


Journal Reference:

  1. Yang et al. Plk1-mediated Phosphorylation of Topors Regulates p53 Stability. Journal of Biological Chemistry, 2009; 284 (28): 18588 DOI: 10.1074/jbc.C109.001560

Cite This Page:

Purdue University. "Key Protein Can Help Cells Or Cause Cancer." ScienceDaily. ScienceDaily, 11 July 2009. <www.sciencedaily.com/releases/2009/07/090707131822.htm>.
Purdue University. (2009, July 11). Key Protein Can Help Cells Or Cause Cancer. ScienceDaily. Retrieved October 25, 2014 from www.sciencedaily.com/releases/2009/07/090707131822.htm
Purdue University. "Key Protein Can Help Cells Or Cause Cancer." ScienceDaily. www.sciencedaily.com/releases/2009/07/090707131822.htm (accessed October 25, 2014).

Share This



More Health & Medicine News

Saturday, October 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Texas Nurse Nina Pham Cured of Ebola

Texas Nurse Nina Pham Cured of Ebola

AFP (Oct. 25, 2014) — An American nurse who contracted Ebola while caring for a Liberian patient in Texas has been declared free of the virus and will leave the hospital. Duration: 01:01 Video provided by AFP
Powered by NewsLook.com
IKEA Desk Converts From Standing to Sitting With One Button

IKEA Desk Converts From Standing to Sitting With One Button

Buzz60 (Oct. 24, 2014) — IKEA is out with a new convertible desk that can convert from a sitting desk to a standing one with just the push of a button. Jen Markham explains. Video provided by Buzz60
Powered by NewsLook.com
Ebola Protective Suits Being Made in China

Ebola Protective Suits Being Made in China

AFP (Oct. 24, 2014) — A factory in China is busy making Ebola protective suits for healthcare workers and others fighting the spread of the virus. Duration: 00:38 Video provided by AFP
Powered by NewsLook.com
WHO: Millions of Ebola Vaccine Doses by 2015

WHO: Millions of Ebola Vaccine Doses by 2015

AP (Oct. 24, 2014) — The World Health Organization said on Friday that millions of doses of two experimental Ebola vaccines could be ready for use in 2015 and five more experimental vaccines would start being tested in March. (Oct. 24) Video provided by AP
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:

Strange & Offbeat Stories

 

Health & Medicine

Mind & Brain

Living & Well

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