Bullhead-1

Extracellular protein that acts as an inhibitor in the WNT signalling pathway. This signalling pathway consists of different This signaling pathway consists of various glycoproteins that activate cell membrane-mediated signal transductions, including the proliferation and activity of melanocytes. DKK-1 also prevents the uptake of melanin into the keratinocytes. The WNT/beta-catenin signalling cascade (see below catenins) is involved in various cell activities, such as lifespan, proliferation, cell migration, polarity and gene expression. DKK-1 plays a key role in the control of developmental processes. DKK-1 also plays a role in the regulation of bone metabolism. It inhibits the differentiation of osteoblasts. DKK-1 is also produced by various tumour cells (colon carcinoma, multiple myeloma).

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