HOME >> BIOLOGY >> NEWS
Protein essential for making steroids turns out to be a "molten globule"

he body," Miller said. "Hormone replacement therapy can save their lives, but the children also must receive mineralcorticoid and glucocorticoid replacements throughout their lives to help maintain salt and sugar balance."

Miller's lab has been working in cooperation with Michael Baldwin, PhD, and Thomas James, PhD, in the department of pharmaceutical chemistry at UCSF to determine the structure of StAR and learn how it works.

Miller credits Bose, a postdoctoral fellow with a background in physical chemistry, for enlisting help from Baldwin, James and other UCSF experts in protein spectroscopy to study how the StAR protein is folded into its final shape. Most proteins are not active in this incompletely folded state, but Bose concluded that StAR does its work of ushering cholesterol into the mitochondria when it is partially unfolded.

That may be because the ports that allow entry into mitochondria are very small, Bose said. "Think of a protein as a ball of spaghetti. It can only get into the mitochondria one strand at a time." A section of the protein called the "mitochondrial leader" enters a port. Inside the mitochondria, import machinery begins to pull the protein in - as if it were slurping in a strand of spaghetti. StAR unfolds to enter the port, but a compactly folded section of the protein unfolds more slowly and creates a pause in the process.

In their article for The Proceedings of the National Academy of Sciences, Bose, Miller and their colleagues propose that this flexible, "molten globule" conformation lowers the energy required for a channel to open in the mitochondrial membrane. In this form, StAR appears to function as an on/off switch for cholesterol flowing from the cell into the mitochondria. If so, it may be the first protein found that does its work in a molten globule state. More studies are necessary to determine StAR's exact structure and to work out the details of how it shepherds cholesterol into the mitochondria to be
'"/>

Contact: Janet Basu
jbasu@pubaff.ucsf.edu
415-476-2557
University of California - San Francisco
22-Jun-1999


Page: 1 2 3

Related biology news :

1. Protein is key to fatal disorder and normal cell function
2. Protein is key for digestive function of the pancreas
3. Proteins show promise for mosquito control
4. Protein involved in childhood disorder linked to cancer
5. Protein fishing in America: The movie
6. Protein vaccine fully protects mice from lethal aerosol challenge with ricin toxin
7. Protein key to trafficking in nerve terminals
8. Protein controls acid in cells by direct detection of volume changes, study finds
9. Protein believed to control formation of memory identified by Scripps & UCSD scientists
10. Protein stops blood-vessel growth, holds promise as cancer therapy
11. Proteins transform DNA into molecular velcro

Post Your Comments:
*Name:
*Comment:
*Email:
TAG: Protein essential for making steroids turns out molten globule

(Date:11/6/2014)... is an asset for a predator. Except when that predator ... tiger beetle, relative to its size, is the fastest creature ... body lengths per second (at about five miles per hour). ... take the sprinting gold from the tiger beetle, a person ... The tiger beetle has a problem. At peak speeds, everything ...
(Date:11/5/2014)... Janeiro, Brazil -Individuals show great diversity in their ability ... and females greatly differ in their perceptual evaluation of ... smell tests. , Sex differences in olfactory ... and may be connected to one,s perception of smell, ... Thus, women,s olfactory superiority has been suggested to be ...
(Date:11/4/2014)... CORAL GABLES, Fla. (November 4, 2014) — Think about ... and ask: How do neighboring cells know that they ... cell and how do these tissues find the correct ... (UM) are answering these crucial questions. , In a ... tissues use to communicate with their surrounding neighbors, at ...
Breaking Biology News(10 mins):The tiger beetle: Too fast to see 2The female nose always knows: Do women have more olfactory neurons? 2The inside story: How the brain and skull stay together 2
(Date:11/21/2014)... Why did Stephen Hawking become so famous? ... recognizable? Why have they become icons to rival film ... Ratcliffe seeks out the answers to those questions, and ... with science. In " Stephen Hawking Smoked My Socks ... Ratcliffe puts it plainly: , “It is profoundly ...
(Date:11/21/2014)... Nov. 20, 2014 /CNW/ - Aequus Pharmaceuticals Inc. ... that it has closed a brokered private placement ... approximately C$3.7 million.  Cormark Securities Inc. and Clarus ... Brokered Offering for a syndicate of agents that ... Corp. (collectively the "Agents"). Concurrently with the Brokered ...
(Date:11/18/2014)... 17, 2014 RPS Diagnostics (RPS®) ... – today announces its third annual partnership of ... Get Smart About Antibiotics Week from November 17-23. ... national campaign designed to highlight the coordinated efforts ... non-profit and for-profit partners to provide education about ...
(Date:11/18/2014)... (PRWEB) November 18, 2014 Alanda ... and Transparency Reporting solutions, announced today that a ... using its Consummate Provider™ solution in both the ... a Global, SaaS based, Data Quality remediation portal, ... their third party Providers improve their ability to ...
Breaking Biology Technology:“Stephen Hawking Smoked My Socks” Sparks Controversy in Science World 2“Stephen Hawking Smoked My Socks” Sparks Controversy in Science World 3“Stephen Hawking Smoked My Socks” Sparks Controversy in Science World 4Aequus Pharmaceuticals closes $4.2 million private placement financing 2Aequus Pharmaceuticals closes $4.2 million private placement financing 3RPS Again Partners with the CDC in Support of the 2014 Get Smart About Antibiotics Week 2RPS Again Partners with the CDC in Support of the 2014 Get Smart About Antibiotics Week 3Alanda Software Completes Successful Implementation of Global Data Quality & Vendor Management Solution for Top Tier Global Biopharmaceutical Company 2
Cached News: