Navigation Links
The key (proteins) to self-renewing skin
Date:7/5/2012

In the July 6 issue of Cell Stem Cell, researchers at the University of California, San Diego School of Medicine describe how human epidermal progenitor cells and stem cells control transcription factors to avoid premature differentiation, preserving their ability to produce new skin cells throughout life.

The findings provide new insights into the role and importance of exosomes and their targeted gene transcripts, and may help point the way to new drugs or therapies for not just skin diseases, but other disorders in which stem and progenitor cell populations are affected.

Stem cells, of course, are specialized cells capable of endlessly replicating to become any type of cell needed, a process known as differentiation. Progenitor cells are more limited, typically differentiating into a specific type of cell and able to divide only a fixed number of times.

Throughout life, human skin self-renews. Progenitor and stem cells deep in the epidermis constantly produce new skin cells called keratinocytes that gradually rise to the surface where they will be sloughed off. One of the ways that stem and progenitor cells maintain internal health during their lives is through the exosome a collection of approximately 11 proteins responsible for degrading and recycling different RNA elements, such as messenger RNA that wear out or that contain errors resulting in the translation of dysfunctional proteins which could potentially be deleterious to the cell.

"In short," said George L. Sen, PhD, assistant professor of medicine and cellular and molecular medicine, "the exosome functions as a surveillance system in cells to regulate the normal turnover of RNAs as well as to destroy RNAs with errors in them."

Sen and colleagues Devendra S. Mistry, PhD, a postdoctoral research fellow, and staff scientist Yifang Chen, MD, PhD, discovered that in the epidermis the exosome functions to target and destroy mRNAs that encode for transcription factors that induce differentiation. Specifically, they found that the exosome degrades a transcription factor called GRHL3 in epidermal progenitor cells, keeping the latter undifferentiated. Upon receiving differentiation inducing signals, the progenitor cells lose expression of certain subunits of the exosome which leads to higher levels of GRHL3 protein. This increase in GRHL3 levels promotes the differentiation of the progenitor cells.

"Without a functioning exosome in progenitor cells," said Sen, "the progenitor cells prematurely differentiate due to increased levels of GRHL3 resulting in loss of epidermal tissue over time."

Sen said the findings could have particular relevance if future research determines that mutations in exosome genes are linked to skin disorders or other diseases. "Recently there was a study showing that recessive mutations in a subunit of the exosome complex can lead to pontocerebellar hypoplasia, a rare neurological disorder characterized by impaired development or atrophy of parts of the brain," said Sen. "This may potentially be due to loss of progenitor cells. Once mutations in exosome complex genes are identified in either skin diseases or other diseases like pontocerebellar hypoplasia, it may be possible to design drugs targeting these defects."


'/>"/>

Contact: Scott LaFee
slafee@ucsd.edu
619-543-6163
University of California - San Diego
Source:Eurekalert  

Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
The key (proteins) to self-renewing skin
(Date:3/24/2017)... , ... March 24, 2017 , ... According to a ... is invalid because it does not obey the rules Congress has directed the CBO ... jobs, which the GOP reform would restore. Yet, it estimates a reduction in employer-based ...
(Date:3/24/2017)... ... March 24, 2017 , ... The iaedp Foundation, the premier provider ... caring for those suffering from the full spectrum of disordered eating, announced today that ... professionals from nearly all 50 states and several countries converged on the Green Valley ...
(Date:3/24/2017)... ... 2017 , ... Shamanic healer and teacher Anahata Ananda of ... Awakening, proudly presents her Sacred Peru retreat with world famous shaman and ... during the Summer Solstice will also be her final international retreat, Anahata announced ...
(Date:3/24/2017)... ... March 24, 2017 , ... As the ... create a communications platform that positions them as the go-to thought leader in ... their online publication as an always-on, always-fresh news, views and advocacy engine, called ...
(Date:3/24/2017)... (PRWEB) , ... March 24, 2017 , ... ... two panels at the Advanced ERISA Benefit Claims Litigation seminar in Chicago, Illinois. ... the Administrative Record, The majority of cases litigated under ERISA involve claims for ...
Breaking Medicine News(10 mins):
(Date:3/24/2017)... 2017  HealthMine surveys with 9,250 insured consumers fielded ... plan members want help from their plans in five ... their health, 2) help closing gaps in care, 3) ... and 5) relevant, real-time guidance. Meeting these needs is ... A Reason to Stay Engaged ...
(Date:3/23/2017)... 2017 Research and Markets has announced the ... Industry Forecast to 2025" report to their offering. ... The Global Cryostat Market ... the next decade to reach approximately $3.5 billion by 2025. ... all the given segments on global as well as regional levels ...
(Date:3/23/2017)... -- Executive Summary ... research (inputs from industry experts, companies, stakeholders) and ... analysis of global heart valve devices market on ... Procedure By Technique (Mechanical, Bioprosthetic, Transcatheter Aortic Valve ... Valvuloplasty, Transcatheter Mitral Valve Repair (TMVR)), By Region ...
Breaking Medicine Technology: