protein_function: Cytokine that promotes the proliferation, survival anddifferentiation of monocytes and macrophages. Promotes the releaseof proinflammatory chemokines, and thereby plays an important rolein innate immunity and in inflammatory processes. Plays animportant role in the regulation of osteoclast proliferation anddifferentiation, and in the regulation of bone resorption.Signaling via CSF1R and its downstream effectors stimulatesphosphorylation of MAPK1,ERK2 AND MAPK3,ERK1 (By similarity)..
Interleukin-34, or IL-34 is a protein belonging to a group of cytokines called interleukins. It is mapped to 16q22.1. The discovery of IL-34 protein in the red pulp of the spleen suggests involvement in growth and development of myeloid cells, consistent with its activity on monocytes. IL-34 is a recently discovered cytokine that acts on tissue resident macrophages and Langerhans cells upon binding the receptor for CSF-1, CSF-1R. It also can promote the differentiation and viability of monocytes and macrophages through the colony-stimulating factor-1 receptor. In addition, it promotes the development, survival, and function of microglia and Langerhans cells, therefore, this cytokine may predominately function in brain and skin biology.