Navigation Links
Researchers develop assay that could be applied to drug screening

Using state of the art imaging technology a team from Yale School of Medicine has glimpsed one of the cell's most important 'nano-machines' in action. The work, performed in collaboration with English and French scientists, provides new insight into the machinery cells use to internalize cell surface receptors.

All cells traffic protein cargos across their outer membrane, and one of the most important routes for cargo internalization is clathrin mediated endocytosis (CME). CME is of fundamental importance for many cellular activities including receptor down-regulation, nutrient uptake and maintenance of signal transmission across nerve cell junctions. Mis-regulation of CME has been implicated in some types of cancer and neuro-degenerative disease and the protein machinery of CME has been co-opted by several viruses, including rabies, as a means of entry into healthy cells.

The researchers led by David Zenisek, assistant professor in the Department of Cellular and Molecular Physiology at Yale School of Medicine, used live cell imaging and a novel fluorescence assay to visualize the formation of clathrin-coated vesicles (CCVs) at single clathrin-coated pits (CCPs) with a time resolution of seconds.

"Although the basic model of clathrin-mediated endocytosis was proposed 41years ago, there are many basic questions outstanding," Zenisek said. "For instance, it wasn't known whether single clathrin coated pits give rise to single clathrin coated vesicles. We have now shown directly that coated pits can produce multiple vesicles in succession."

Using a specially adapted microscope, Zenisek and his colleagues Christien Merrifield and David Perrais, simultaneously measured the minute movements made by coated pits as they invaginated and detected membrane scission, the process by which a coated pit is converted into a clathrin coated vesicle. In further experiments, the researchers showed how proteins linked to the actin framework of the cell are brought to sites of coated pit. Actin is a protein polymer used by cells both as a structural element, and to generate force through polymerization.

"The role played by actin in clathrin mediated endocytosis has been controversial for a long time," Zenisek said. "We've now shown in live cells that proteins involved in actin polymerization are recruited to sites of membrane scission, and that disturbing actin polymerization with the toxin latrunculin B, a toxin found in Red Sea sponge, drastically reduces the efficiency of membrane scission and affects many aspects of CCP dynamics."


Source:Yale University

Related biology news :

1. Researchers discover way to make cells in the eye sensitive to light
2. Researchers find how protein allows insects to detect and respond to pheromones
3. Researchers Uncover Key Step In Manufacture of Memory Protein
4. Researchers reveal the infectious impact of salmon farms on wild salmon
5. Researchers identify target for cancer drugs
6. Researchers discover molecule that causes secondary stroke
7. Researchers find missing genes of ancient organism
8. Researchers trace evolution to relatively simple genetic changes
9. Researchers add new tool to tumor-treatment arsenal
10. UF Researchers Map Bacterial Proteins That Cause Tooth Loss
11. VCU Researchers Identify Networks Of Genes Responding To Alcohol In The Brain
Post Your Comments:

(Date:11/9/2015)... 2015 ... "Global Law Enforcement Biometrics Market 2015-2019" ... ) has announced the addition ... Market 2015-2019" report to their offering. ... ) has announced the addition of ...
(Date:11/2/2015)... Calif. , Nov. 2, 2015  SRI International ... million to provide preclinical development services to the National ... contract, SRI will provide scientific expertise, modern testing and ... variety of preclinical pharmacology and toxicology studies to evaluate ... --> The PREVENT Cancer Drug Development Program ...
(Date:10/29/2015)... 2015 Daon, a global leader in mobile ... a new version of its IdentityX Platform , ... America have already installed IdentityX v4.0 and ... FIDO UAF certified server component as an ... FIDO features. These customers include some of the largest ...
Breaking Biology News(10 mins):
(Date:11/25/2015)... , November 25, 2015 ... Report is a professional and in-depth study on ...      (Logo: ) , ... the industry including definitions, classifications, applications and industry ... for the international markets including development trends, competitive ...
(Date:11/24/2015)... , Nov. 24, 2015 Halozyme Therapeutics, Inc. (NASDAQ: ... in New York on Wednesday, December 2 ... Torley , president and CEO, will provide a corporate overview. ... York at 1:00 p.m. ET/10:00 a.m. PT . ... relations, will provide a corporate overview. --> th ...
(Date:11/24/2015)... -- Clintrax Global, Inc., a worldwide provider of clinical research services headquartered ... the company has set a new quarterly earnings record in Q3 ... posted for Q3 of 2014 to Q3 of 2015.   ... , with the establishment of an Asia-Pacific ... United Kingdom and Mexico , with ...
(Date:11/24/2015)... 2015 --> ... released by Transparency Market Research, the global non-invasive prenatal ... of 17.5% during the period between 2014 and 2022. ... Industry Analysis, Size, Volume, Share, Growth, Trends and Forecast ... market to reach a valuation of US$2.38 bn by ...
Breaking Biology Technology: