Fandom

VroniPlag Wiki

Analyse:Rsi/Fragment 015 01

31.358Seiten in
diesem Wiki
Seite hinzufügen
Diskussion0

Störung durch Adblocker erkannt!


Wikia ist eine gebührenfreie Seite, die sich durch Werbung finanziert. Benutzer, die Adblocker einsetzen, haben eine modifizierte Ansicht der Seite.

Wikia ist nicht verfügbar, wenn du weitere Modifikationen in dem Adblocker-Programm gemacht hast. Wenn du sie entfernst, dann wird die Seite ohne Probleme geladen.


Typus
Verschleierung
Bearbeiter
Klgn
Gesichtet
No.png
Untersuchte Arbeit:
Seite: 15, Zeilen: 1 ff.
Quelle: Martinez-Agosto et al. 2007
Seite(n): 3048, 3050, Zeilen: -
1.4 The importance of the HSC niche:

Key properties of stem cells such as their self-renewal and developmental capacity can be controlled in a non autonomous manner by their cellular microenvironment. Such a microenvironment is usually referred to as a stem cell niche. A niche is a group of cells that allows a stem cell to maintain its identity [21]. The cells of a niche will prevent a previously specified cell from losing its stemness through loss of quiescence and potency or precocious differentiation. In the best demonstrations of a niche, a specific signaling pathway or a cell adhesion molecule is identified that allows the niche cells to maintain contact with stem cells and typically in the absence of such a mechanism, the stem cells leave their niche and either divide, differentiate, or apoptose [21].

The niche and the stem cells may arise from the same progenitor population, as is the case of the origin of HSC and endothelial cells of the dorsal aorta, which share a common progenitor in their ancestry [47], and the placenta in mice [48].

A niche could be derived completely separately from the stem cell, as is the case for the bone marrow hematopoietic niche, which utilizes signals derived from osteoblasts and mesenchymal stromal cells, both of which, although mesodermal, have different developmental origins from the HSC [49].In the mouse adult bone marrow, N-cadherin is expressed in the HSC and the spindle-shaped osteoblastic cells of the niche [50]. Mammalian hematopoiesis gives rise to long-term reconstituting HSC that, in turn, generate short-term repopulating HSC [51]. From these stem cells a number of more restricted progenitors emerge that give rise to all differentiated blood cells in adult circulation, such as lymphoid, myeloid, and erythroid cells [52]. Each of these progenitors can be distinguished by a subset of cell surface markers. Development of the initial definitive HSC requires Runx-1 [53], and its expression later continues in differentiating myeloid and lymphoid cells [54]. Later inactivation of Runx1 within the bone marrow is not essential for adult hematopoiesis, but it does affect maturation of lymphocytes and platelets [55].

[S. 3048]

Key properties of stem cells such as their self-renewal and developmental capacity can be controlled in a nonautonomous manner by their cellular microenvironment. Such a microenvironment is usually referred to as a stem cell niche (Fig. 3). [...] A niche is a group of cells that allows a stem cell to maintain its identity (Scadden 2006). The cells of a niche will prevent a previously specified cell from losing its stemness through loss of quiescence and potency or precocious differentiation. In the best demonstrations of a niche, a specific signaling pathway or a cell adhesion molecule is identified that allows the niche cells to maintain contact with stem cells and typically in the absence of such a mechanism, the stem cells leave their niche and either divide, differentiate, or apoptose (Scadden 2006).

[...]

The niche and the stem cells may arise from the same progenitor population, as is the case of the origin of HSC and endothelial cells of the dorsal aorta, which share a common progenitor in their ancestry (Jaffredo et al. 1998), and the placenta in mice (Gekas et al. 2005). [...] Finally, a niche could be derived completely separately from the stem cell, as is the case for the bone marrow hematopoietic niche, which utilizes signals derived from osteoblasts and mesencymal stromal cells, both of which, although mesodermal, have different developmental origins from the HSC (Wilson and Trumpp 2006).

[S. 3050]

In the mouse adult bone marrow, N-cadherin is expressed in the HSC and the spindle-shaped osteoblastic cells of the niche (Zhang et al. 2003).

[...]

Mammalian hematopoiesis gives rise to long-term reconstituting HSCs that, in turn, generate short-term repopulating HSCs (Eaves et al. 2001). From these stem cells a number of more restricted progenitors emerge that give rise to all differentiated blood cells in adult circulation, such as lymphoid, myeloid, and erythroid cells (Akashi 2005). Each of these progenitors can be distinguished by a subset of cell surface markers. Development of the initial definitive HSC requires Runx-1 (North et al. 2002), and its expression later continues in differentiating myeloid and lymphoid cells (North et al. 2004). Later inactivation of Runx1 within the bone marrow is not essential for adult hematopoiesis, but it does affect maturation of lymphocytes and platelets (Growney et al. 2005).

Anmerkungen
Sichter

Auch bei Fandom

Zufälliges Wiki