Navigation Links
Primitive yeast yields secrets of human cholesterol and drug metabolism

By first probing the way primitive yeast make cholesterol, a team of scientists has discovered a long-sought protein whose human counterpart controls cholesterol production and potentially drug metabolism.

The collaborative study by investigators at Johns Hopkins University School of Medicine, Vanderbilt University, Indiana University and Eli Lilly Co., was published in the February issue of Cell Metabolism.

“Dap1 controls the activity of a clinically important class of enzymes required for cholesterol synthesis and drug metabolism,?says Peter Espenshade, Ph.D., assistant professor of cell biology at Johns Hopkins. “We’re excited because although we originally identified this protein in yeast, humans not only have the same protein, but it works the same way.?

The search for Dap1 began with the hunt for factors that influence the actions of a large family of enzymes called cytochrome P450. These enzymes control many life-sustaining chemical reactions in humans and other animals.

Happily, Espenshade says, yeast have only two P450 enzymes, and both play roles in making cholesterol, narrowing down the territory for their search and giving them a telltale marker (the cholesterol) to track.

Reasoning that whatever controls the P450s likely would be turned on and off at roughly the same time as the P450 enzymes themselves, the researchers found that Dap1 does just that in the yeast cell.

To figure out what Dap1 does, Espenshade and colleagues genetically altered yeast cells to lack Dap1. Those cells predictably were unable to make cholesterol and instead contained a build-up of cholesterol precursors.

The research team then tracked Dap1’s counterpart in humans by looking for similar proteins in a computer database and repeated their experiments in human kidney cells engineered to lack the human version of Dap1. As in yeast, the altered human cells accumulated cholesterol precursors and died because cholest erol is essential for cell survival.

To show that Dap1 directly works with P450s and not through some other biochemical steps, Espenshade’s team tested the ability of human Dap1 protein to bind to four of the 57 known human P450 enzymes, essentially challenging Dap1 to bind to P450s that perform totally different functions in different cells as a way to see how far-reaching its control might be.

Dap1 locked on to all four P450s, including one required for clearing half of all known drugs from the body, another involved in making bile and one required for making natural steroid hormones in the adrenal glands.

“Collectively, our experiments suggest that Dap1 acts as a common regulator of cytochrome P450s in mammals,?says Espenshade.

Because Dap1 affects one particular P450 responsible for drug metabolism, Espenshade suspects that genetic variations in the genetic blueprint coding for Dap1 may provide clues to how and why different people react differently to certain drugs.

“Understanding the molecular underpinnings of so-called pharmacogenetic variation will have a big impact on the future of medicine,?he says.
'"/>

Source:Johns Hopkins Medical Institutions


Related biology news :

1. Examination of internal wiring of yeast, worm, and fly reveals conserved circuits
2. Navigating an integrated yeast network
3. After the yeast is gone bacteria continue to develop flavor of sparkling wine
4. GlycoFi announces the first production of antibodies with human glycosylation in yeast
5. From a lowly yeast, researchers divine a clue to human disease
6. GlycoFi and Dartmouth report full humanization of yeast glycosylation pathway in Science
7. Engineered yeast speeds ethanol production
8. Hives ferment a yeasty brew, attract beetle pest
9. Genome-wide mouse study yields link to human leukemia
10. Marine sponge yields nanoscale secrets
11. Small worm yields big clue on muscle receptor action

Post Your Comments:
*Name:
*Comment:
*Email:


(Date:6/22/2016)... -- The American College of Medical Genetics and Genomics was once ... one of the fastest-growing trade shows during the Fastest 50 ... Las Vegas . Winners ... each of the following categories: net square feet of paid ... The 2015 ACMG Annual Meeting was ranked 23 out of ...
(Date:6/16/2016)... June 16, 2016 The ... expected to reach USD 1.83 billion by 2024, ... Research, Inc. Technological proliferation and increasing demand in ... expected to drive the market growth. ... The development of advanced multimodal techniques for ...
(Date:6/3/2016)... , June 3, 2016 ... Management) von Nepal ... und Lieferung hochsicherer geprägter Kennzeichen, einschließlich Personalisierung, ... führend in der Produktion und Implementierung von ... der Ausschreibung im Januar teilgenommen, aber Decatur ...
Breaking Biology News(10 mins):
(Date:11/30/2016)... 2016 Part of 5m$ Investment in ... ... Aptuit, LLC today announced that it had successfully completed the ... compounds have increased the Screening Collection to over 400,000. The ... capabilities of the company. This expansion, complemented by new robotics ...
(Date:11/30/2016)... ... November 30, 2016 , ... ... advanced technology applications, introduces the 5th generation, ultra-bright, Laser-Driven Light Source, the EQ-77, ... Light Source (LDLS™) technology, the EQ-77 offers higher radiance and irradiance from a ...
(Date:11/30/2016)... ... November 30, 2016 , ... With growth rates averaging more than 30% ... and look forward to continuing their expansion in their new office space. The new ... been traditionally favoured by the creative industries, so Random42 Scientific Communication will fit right ...
(Date:11/30/2016)... GREENWICH, Connecticut , November 30, 2016 ... für die integrierte Medikamententdeckung    ... , , ... führende Prüfbibliothek erfolgreich erweitert zu haben. Zusätzliche 150.000 neuartige ... neuen Substanzen wurden sorgfältig ausgewählt, um die starken Entdeckungsfähigkeiten ...
Breaking Biology Technology: