or less Regulating stem cell self-renewal and differentiation with bone morphogenetic protein signalling

In the skin stem cell niche, bone morphogenetic protein (BMP) signalling is an integral regulator of stem cell self-renewal and differentiation. This niche is a population of epidermal stem cells which lies at the base of the interfollicular epidermis and is responsible for maintaining skin homeostasis and repair. This niche is highly heterogeneous in its cellular composition, consisting of stem cells and skin-resident macrophages, keratinocytes, and melanocytes. Recent studies have demonstrated that BMP signalling plays an important role in maintaining the stem cell niche. BMPs are members of the transforming growth factor (TGF) beta superfamily of cytokines and act through the receptors BMPR-IA and BMPR-IB to regulate various cellular processes, including the differentiation and self-renewal of stem cells. BMP signalling has been shown to promote the self-renewal and activation of adult epidermal stem cells. for example, a study by Prendergast et al. (2013) demonstrated that the expression of BMPR-IA was upregulated in wounded areas of the skin, suggesting it may contribute to stem cell activation and wound healing. Moreover, BMP signalling appears to be essential for stem cell maintenance, as well as promoting their differentiation into wound-healing keratinocytes. In addition, BMP signalling has been shown to contribute to the maintenance of stem cell quiescence. In a study by Burg and Fuchs (2009), BMP4 was found to regulate the transcription of p63 and its downstream target, p21, which suppresses the cell-cycle progression of keratinocytes and allows them to remain quiescent. Moreover, BMP4 signalling has also been shown to prevent the differentiation of epidermal stem cells, supporting its role in maintaining the epidermal stem cell niche. Furthermore, BMP signalling can also regulate the niche microenvironment and suppress damaging inflammation. For example, a study by Garoni et al. (2012) demonstrated that BMP signalling suppresses the production of inflammatory cytokines such as IL-1beta, IL-6 and TNF-alpha, suggesting it may play a role in mediating the inflammatory response. In summary, BMP signalling has been shown to regulate stem cell self-renewal and differentiation in the skin stem cell niche. It is critical for the maintenance of the niche, by regulating