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:


(Date:3/28/2017)... 2017 The report "Video Surveillance ... Servers, Storage Devices), Software (Video Analytics, VMS), and Service ... Forecast to 2022", published by MarketsandMarkets, the market was ... projected to reach USD 75.64 Billion by 2022, at ... base year considered for the study is 2016 and ...
(Date:3/24/2017)... , March 24, 2017 The Controller General ... Controller Mr. Abdulla Algeen have received the prestigious international IAIR ... Continue Reading ... ... picture) and Deputy Controller Abdulla Algeen (small picture on the right) have ...
(Date:3/23/2017)... 23, 2017 The report "Gesture Recognition and Touchless Sensing ... Geography - Global Forecast to 2022", published by MarketsandMarkets, the market is expected ... 29.63% between 2017 and 2022. Continue Reading ... ... ...
Breaking Biology News(10 mins):
(Date:4/27/2017)... WASHINGTON , April 27, 2017  Kinexum, a ... science products, today announces the appointment of Thomas ... G. Alexander ("Zan") Fleming, M.D., Kinexum founder, who becomes ... strategic advisor to Kinexum clients. Thomas ... take on the Kinexum mission and lead the firm,s ...
(Date:4/26/2017)... (PRWEB) , ... April 26, 2017 , ... ... has teamed up with NASA to showcase the future of deep space exploration ... System (SLS) rocket and Orion spacecraft and includes a guest appearance by former ...
(Date:4/26/2017)... Centennial, CO (PRWEB) , ... April 25, 2017 , ... ... test offerings were added to its extensive test menu: Nucleic Acid Testing (NAT) ... that time, LABS was only able to offer NAT screening for blood donors under ...
(Date:4/26/2017)... ... April 26, 2017 , ... ... EMEA and North America this May on the following dates: ... Donald H. Taylor, Chairman of the Learning and Performance Institute will be the ...
Breaking Biology Technology:
Cached News: