Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Splitting hairs: GATA-3 function in hair follicle development

22.08.2003


A group of scientists led by Dr. Elaine Fuchs at the Howard Hughes Medical Institute at the Rockefeller University have uncovered an unexpected new role for the well-known transcription factor, GATA-3, in hair follicle development. GATA-3 was previously identified for its role in coaxing hematopoietic stem cells towards a T-cell fate. Now, Dr. Fuchs and colleagues reveal that GATA-3 is also involved in epidermal stem cell specification. This finding lends valuable insight into hair follicle generation, and highlights intriguing parallels between the molecular cues that direct cell fate specification in the skin and the immune system.





Each of the roughly 5 million hair follicles that cover the adult human body has a similar structure. The hair follicle consists of a multi-layered hair shaft, the outermost layer of which is referred to as the cuticle. Below the skin surface, the cuticle is surrounded by an inner root sheath (IRS).

"The IRS acts as a channel, functioning to guide the developing hair shaft up to the skin surface. Without the channel, the hair does not develop properly," explains professor Fuchs.


In an effort to understand how cells are directed towards an IRS fate, Dr. Fuchs and two MD/PhD students, Charles Kaufman and Diana Bolotin, used microarray analysis to monitor gene expression levels in the dorsal (back) skin of embryonic mice. GATA-3 emerged as one gene that was turned on during hair morphogenesis. Further work by Dr. Fuchs and colleagues revealed that the GATA-3 protein is specifically expressed in IRS cells of the hair follicle.

These findings, coupled with existing knowledge of GATA-3’s function as a master gene regulator of cell lineage specification in the immune system, posited GATA-3 as an attractive candidate for directing epidermal stem cells to become IRS cells.

To investigate the precise role of GATA-3 in hair follicle morphogenesis, Dr. Fuchs and colleagues turned to a strain of GATA-3-deficient mice to observe what defects, if any, appeared in these mice. However, since GATA-3-deficient mice die in utero well before hair follicles develop, Dr. Fuchs and colleagues used a drug rescue regime to help these embryos to survive until embryonic day 18.5, when at least the whiskers have matured. As suspected, these pharmacologically rescued GATA-3-null mice did, in fact, show a number of abnormalities in hair development.

Dr. Fuchs and colleagues discovered that GATA-3-deficient follicles fail to develop cells of the IRS, and as a result, generate hair with severe structural anomalies.

The whisker follicles of pharmacologically rescued GATA-3-null mice were oddly bent, and displayed irregular thickenings and delayed emergence through the skin. However, for as unusual as their whiskers appeared, the remainder of the epidermis of these pharmacologically rescued GATA-3-null mice appeared to function properly.

When Dr. Fuchs and colleagues grafted dorsal skin from pharmacologically rescued GATA-3-null mice onto GATA-3-normal mice, and thereby allowed the hair follicles more time to develop, they noticed further distortions. The GATA-3-null skin grafts failed to grow normal fur. Even after almost a month, the GATA-3-null grafts generated nothing more than short stubble. Furthermore, the hairs that did finally emerge were short, thick, and had an irregular cuticle pattern (see photo from electron microscopist, Dr. Amalia Pasolli).

"These studies bring us one step closer to understanding the key components that go into making a hair follicle. Over the past few years, we and others in the field have identified critical signals for making the hair itself. Now, we’ve uncovered an important missing factor in creating the channel, which must develop coordinately with the hair. In addition, the finding sheds new light on the striking parallels between how stem cells in the bone marrow and those in the skin undergo differentiation in the body."

Heather Cosel | EurekAlert!
Further information:
http://www.cshl.org/

More articles from Life Sciences:

nachricht A novel socio-ecological approach helps identifying suitable wolf habitats
17.02.2017 | Universität Zürich

nachricht New, ultra-flexible probes form reliable, scar-free integration with the brain
16.02.2017 | University of Texas at Austin

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Biocompatible 3-D tracking system has potential to improve robot-assisted surgery

17.02.2017 | Medical Engineering

Real-time MRI analysis powered by supercomputers

17.02.2017 | Medical Engineering

Antibiotic effective against drug-resistant bacteria in pediatric skin infections

17.02.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>