Integrin-dependent anchoring of a stem-cell niche (Nat Cell Biol, 2007, 9:1413-1418)

報告日期: 2008/05/27
報告時間: 15:10/16:00
報告學生: 許家豪
講評老師: 莫凡毅
附件下載:

http://basicmed.med.ncku.edu.tw/admin/up_img/970527-1.pdf

Integrin-dependent anchoring of

a stem-cell niche

Nature Cell Biology 9, 1413 - 1418 (2007)

 

Speaker: Jia-Hau Shiu (許家豪)

Commentator: Prof. Fan-E Mo (莫凡毅)

Date: 05/27/08

Time: 15:10~16:00

Place: Room 602

 

Abstract:

 

Stem cells are characterized by their ability to self-renew and produce numerous differentiated cell types. They are directly responsible for generating and maintaining tissues and organs. The diverse behaviors of stem cells are usually regulated by their local microenvironment, which are often referred to as the ‘stem-cell niche’. Stem cells in the Drosophila systems provide excellent models to understand the fundamental relationships between stem cells and their niches. In this study, the authors showed the stem-cell niche in the Drosophila testis that was composed of a tightly clustered group of somatic cells known as the hub. The hub cells were located at the anterior tip of testis and contacted with the germline stem cells (GSCs), which retained their cell morphology in an undifferentiated state. The authors also showed that embryonic hub cells maintain the proper position during gonad morphogenesis, which was mainly mediated by integrin adhesion. The misplaced hub in integrin-deficient embryos could not possess the regular anterior–posterior orientation of dividing GSCs, resulting in an abnormal cell division pattern compared with that in wild-type. Disruption of integrin-mediated adhesion pathway by double-stranded RNA interference in adult testes leaded to a loss of the hub and the stem-cell population, indicating that the hub anchored the surrounding extracellular matrix (ECM) that was essential for gonad development. These results of this study demonstrated that integrin was the key molecule for the attachment of the hub to the ECM and for maintaining the stem-cell niche function.

 

Reference:

1.     Moore, K. A. et al. Stem cells and their niches. Science 311, 1880–1885 (2006).

2.     Xie, T et al. Intimate relationships with their neighbors: tales of stem cells in Drosophila reproductive systems. Dev. Dyn. 232, 775–790(2005).