Navigation Links
Dominant cholesterol-metabolism ideas challenged by new research
Date:8/15/2007

says Schlegel, "that the ABCA1 enzyme was not involved in the transport of phospholipids across the cell membrane under normal conditions."

The team then made use of the fact that the scramblase can be activated in some cells in the laboratory by increasing the concentration of calcium ions. This activation mechanism works best in red blood cells, platelets, lymphocytes, and macrophages and does not work at measurable levels in fibroblasts or epithelial cells. In cells activated by calcium ions, neither the presence nor the absence of ABCA1 changes phospholipids transport. In cells that cannot be activated by adding calcium ions, adding ABCA1 as well does not induce activation. The experiments have the same outcome whether the team used cells from Tangier individuals or knock-out mice. These results suggest strongly that ABCA1 does not code for scramblase and is not required for its activation.

The team then turned to the function of ABC1 in apoptosis. Did ABCA1 cause or activate phospholipid transport across the cell membrane only during apoptosis? "We could not demonstrate that the addition or deletion of ABCA1 had any effect on the movement of PS to the cell surface in apoptotic cells," says Schlegel. "We conclude that the ABCA1 enzyme doesn't influence the transport of PS either under normal conditions or in apoptotic cells."

A third possibility was that ABCA1 functioned only in macrophages to cause the expression of PS on the cell surface. Additional experiments refuted this suggestion too. The absence of ABCA1 did not prevent macrophages from expressing PS on their surfaces. Further, the rate at which macrophages recognized and engulfed their target apoptotic cells remained constant whether ABCA1 was present in the macrophages or not.

"This work really changes our understanding of the mechanics of cholesterol metabolism," remarks Schlegel. "We can't find any evidence whatsoe
'/>"/>

Contact: Barbara K. Kennedy
science@psu.edu
814-863-4682
Penn State
Source:Eurekalert

Page: 1 2 3 4

Related biology news :

1. Past experience of pheromones induces dominant courtship behavior in fruit flies
2. Dominant meerkats render rivals infertile
3. Agriculture and tropical conservation: rethinking old ideas
4. Researchers discover way to make cells in the eye sensitive to light
5. Quantum Dots Research Leads to New Knowledge about Protein Binding in Plants
6. Columbia research lifts major hurdle to gene therapy for cancer
7. Researchers find how protein allows insects to detect and respond to pheromones
8. Researchers Uncover Key Step In Manufacture of Memory Protein
9. Research advances quest for HIV-1 vaccine
10. Research on Worms Yields Clues on Aging
11. U of M researcher examines newly emerging deadly disease
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/23/2015)... 23, 2015 NXT-ID, Inc. (NASDAQ: NXTD ) ("NXT-ID" ... growing mobile commerce market, announces its biometric payment technology, the ... CNBC television starting March 30 th . ... New York markets. ... excited about our new ad campaign following the recent initial ...
(Date:3/20/2015)... , March 20, 2015 NXT-ID, Inc. (NASDAQ: ... authentication company focused on the growing mobile commerce market, ... is one of the products featured in 2015 "I ... at 11:00 PM EST on the DIY Network.   ... Las Vegas , site of the 2015 ...
(Date:3/18/2015)... As mobile payments become more prevalent ... and apps continue to be introduced into the market place ... payment industry in focus today are:  NXT-ID, Inc. (NASDAQ: ... BABA ), Apple Inc. (NASDAQ: AAPL ), Google ... FB ) NXT-ID, Inc. (NASDAQ: ...
Breaking Biology News(10 mins):NXT-ID's Wocket Smart Wallet to Launch New CNBC Regional TV Ad Campaign 2NXT-ID's Wocket Smart Wallet to Launch New CNBC Regional TV Ad Campaign 3NXT-ID's Wocket Biometric Smart Wallet to Air on "I Want That" International CES Special 2NXT-ID's Wocket Biometric Smart Wallet to Air on "I Want That" International CES Special 3Revolutionary Smart Wallet & Mobile Payment Choices Change the Game for Consumers - Company Begins Shipping Newest Digital Wallet to Customers 2Revolutionary Smart Wallet & Mobile Payment Choices Change the Game for Consumers - Company Begins Shipping Newest Digital Wallet to Customers 3Revolutionary Smart Wallet & Mobile Payment Choices Change the Game for Consumers - Company Begins Shipping Newest Digital Wallet to Customers 4Revolutionary Smart Wallet & Mobile Payment Choices Change the Game for Consumers - Company Begins Shipping Newest Digital Wallet to Customers 5Revolutionary Smart Wallet & Mobile Payment Choices Change the Game for Consumers - Company Begins Shipping Newest Digital Wallet to Customers 6
... Oregon,s Willamette Basin to protect at-risk animals won,t necessarily ... absorb more carbon from the atmosphere and vice versa, ... to be published this month in the Proceedings ... payments that were given to landowners to voluntarily take ...
... ocean off the coasts of northern New Jersey and Long ... the four-square-mile patches could not be more different as they ... figure out what lives there and how climate change is ... are much more dynamic than terrestrial landscapes and not what ...
... years of IVF, the rewards of treatment are still ... afford it. Now, a Special Task Force of ESHRE ... treatment more accessible to developing countries through a programme ... and non-governmental agencies. The Task Force faces a ...
Cached Biology News:Incentives for carbon sequestration may not protect species 2Scientists integrate data in three dimensions to study climate effects on young fish 2Scientists integrate data in three dimensions to study climate effects on young fish 3Fertility treatment in developing countries; a cycle of IVF for less than $200 2Fertility treatment in developing countries; a cycle of IVF for less than $200 3
(Date:3/26/2015)... March 26, 2015  Roka Bioscience, Inc. (NASDAQ: ... on providing advanced testing solutions for the detection ... for the three months and full year ended ... Financial Results:Revenue for the quarter ended December 31, ... the fourth quarter of 2013 and $1.5 million ...
(Date:3/26/2015)... 2015 The Market Element LLC, a ... alliance with Designing Gig LLC to provide website design, ... , “Forging this alliance with Designing Gig represents a ... extend a comprehensive, end-to-end, digital solution for our clients, ... said Chuck Miller, president of The Market Element. “For ...
(Date:3/26/2015)... Neogen Corporation (NASDAQ: NEOG ) announced today that ... 2015, which ended Feb. 28, increased 13% to $7,454,000, ... share in the current quarter were $0.20, compared to ... 17% over prior year to $24,142,000, or $0.65 per ... the same period a year ago. Revenues ...
(Date:3/26/2015)... "In America," the popular news television program ... is hosted by legendary film actor James Earl Jones, has ... an upcoming segment. , Botany is commonly described as ... actually quite a bit more complicated than that. Scientists and ... living organisms, from the smallest bacteria known to man to ...
Breaking Biology Technology:Roka Bioscience Reports Fourth Quarter and Full Year 2014 Financial Results 2Roka Bioscience Reports Fourth Quarter and Full Year 2014 Financial Results 3Roka Bioscience Reports Fourth Quarter and Full Year 2014 Financial Results 4Roka Bioscience Reports Fourth Quarter and Full Year 2014 Financial Results 5Roka Bioscience Reports Fourth Quarter and Full Year 2014 Financial Results 6Roka Bioscience Reports Fourth Quarter and Full Year 2014 Financial Results 7The Market Element LLC and Designing Gig LLC Form Strategic Alliance 2Neogen reports 13% increase in net income 2Neogen reports 13% increase in net income 3Neogen reports 13% increase in net income 4Neogen reports 13% increase in net income 5Neogen reports 13% increase in net income 6Neogen reports 13% increase in net income 7Neogen reports 13% increase in net income 8
... Pharmaceuticals,Inc. (NASDAQ: ANPI , TSX: ANP), a ... to participate in the Merrill Lynch,Global Pharmaceutical, Biotechnology ... 5-7 in New York, NY., Dr. William ... to present on Tuesday, February 5, at the ...
... LAKES, N.J., Jan. 29 BD (Becton,Dickinson and Company) ... the,Company,s Annual Meeting of Shareholders today, elected Basil L. ... and Alfred Sommer,to the Board of Directors. The BD ... independent with the exception of Edward J. Ludwig,Chairman, President ...
... BMR ) today announced it will report results for ... market closes on Thursday,February 28, 2008., Alan D. Gold, ... will host an investor conference call at 10:00,a.m. Pacific Time ... and operations for the year., The call will be ...
Cached Biology Technology:BD Announces Results of Shareholder Votes at Annual Meeting 2BioMed Realty Trust To Report 2007 Fourth Quarter and Year-End Results 2
... ATP-Gamma-S binds to ATP-binding proteins. To ... FL fluorophore was linked through the ... its potential use for binding studies ... an important new substrate for Fhit ...
... data, the patent-pending Formula Predictor software ... fragmentation, isotope pattern verification, and unique ... the correct formula for unknown components. ... empirical formulae from mass spec data ...
... a wide variety of purity levels, scales and ... Purity: IG(>50%), >70%, >80% and >95% ... Length: Up to 120 residues ... acids, MAPs, KLH/BSA conjugation, and much more. ...
... With 36 mg/L sodium pyruvate, 50 ... 1000 mg/L glucose, calcium chloride, and magnesium ... solution (BSS) in tissue culture is generally ... In 1885, Sydney Ringer developed a solution ...
Biology Products: