alexa Proliferation and differentiation of spermatogonial stem cells.
Biomedical Sciences

Biomedical Sciences

Journal of Bioengineering & Biomedical Science

Author(s): de Rooij DG

Abstract Share this page

Abstract Spermatogonial stem cells (A(s) spermatogonia) are single cells that either renew themselves or produce A(pr) (paired) spermatogonia predestined to differentiate. In turn, the A(pr) divide into chains of A(al) (aligned) spermatogonia that also divide. The ratio between self-renewal and differentiation of the stem cells is regulated by glial cell line-derived neurotrophic factor produced by Sertoli cells, while the receptors are expressed in stem cells. A(s), A(pr) and A(al) spermatogonia proliferate during part of the epithelial cycle forming many A(al) spermatogonia. During epithelial stage VIII, almost all A(al) spermatogonia, few A(pr) and very few A(s) spermatogonia differentiate into A1 spermatogonia. A number of molecules are involved in this differentiation step including the stem cell factor-c-kit system, the Dazl RNA binding protein, cyclin D(2) and retinoic acid. There is no fine regulation of the density of spermatogonial stem cells and consequently, in some areas, many A1 and, in other areas, few A1 spermatogonia are formed. An equal density of spermatocytes is then obtained by the apoptosis of A2, A3 or A4 spermatogonia to remove the surplus cells. The Bcl-2 family members Bax and Bcl-x(L) are involved in this density regulation. Several mechanisms are available to cope with major or minor shortages in germ cell production. After severe cell loss, stem cell renewal is preferred above differentiation and the period of proliferation of A(s), A(pr) and A(al) spermatogonia is extended. Minor shortages are dealt with, at least in part, by less apoptosis among A2-A4 spermatogonia.
This article was published in Reproduction and referenced in Journal of Bioengineering & Biomedical Science

Relevant Expert PPTs

Relevant Speaker PPTs

Recommended Conferences

Relevant Topics

Peer Reviewed Journals
 
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2017-18
 
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

Agri, Food, Aqua and Veterinary Science Journals

Dr. Krish

[email protected]

1-702-714-7001 Extn: 9040

Clinical and Biochemistry Journals

Datta A

[email protected]

1-702-714-7001Extn: 9037

Business & Management Journals

Ronald

[email protected]

1-702-714-7001Extn: 9042

Chemical Engineering and Chemistry Journals

Gabriel Shaw

[email protected]

1-702-714-7001 Extn: 9040

Earth & Environmental Sciences

Katie Wilson

[email protected]

1-702-714-7001Extn: 9042

Engineering Journals

James Franklin

[email protected]

1-702-714-7001Extn: 9042

General Science and Health care Journals

Andrea Jason

[email protected]

1-702-714-7001Extn: 9043

Genetics and Molecular Biology Journals

Anna Melissa

[email protected]

1-702-714-7001 Extn: 9006

Immunology & Microbiology Journals

David Gorantl

[email protected]

1-702-714-7001Extn: 9014

Informatics Journals

Stephanie Skinner

[email protected]

1-702-714-7001Extn: 9039

Material Sciences Journals

Rachle Green

[email protected]

1-702-714-7001Extn: 9039

Mathematics and Physics Journals

Jim Willison

[email protected]

1-702-714-7001 Extn: 9042

Medical Journals

Nimmi Anna

[email protected]

1-702-714-7001 Extn: 9038

Neuroscience & Psychology Journals

Nathan T

[email protected]

1-702-714-7001Extn: 9041

Pharmaceutical Sciences Journals

John Behannon

[email protected]

1-702-714-7001Extn: 9007

Social & Political Science Journals

Steve Harry

[email protected]

1-702-714-7001 Extn: 9042

 
© 2008-2017 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version
adwords