SCF supports cell survival, proliferation and differentiation. It acts on many types of cells, including but not limited to stem and progenitor cells.
Stem cell factor is a paracrine factor. It activates MITF (microphthalmia- associated transcription factor), which plays a role in melanocyte and osteoclast development by binding to the receptor tyrosine kinase Kit. The absence of SCF leads to an absence of the Kit protein, which in turn can cause genetic heterogeneity- the creation of similar phenotypes from mutations in various genes (ex. anemia, albinism, sterility). SCF is produced by dermal cells. When Kit binds to SCF, it is able to prevent apoptosis and increase cell division of melanoblast precursors. Without Kit and SCF, neural crest cells would not replicate enough to sufficiently cover the skin. SCF is also needed for the survival and movement of primordial germ cells. It has yet another important function in regulating hematopoietic stem cells (HSCs) in the bone marrow. Without SCF, HSCs, which are undifferentiated and pluripotent stem cells, will die.
Vocabulary:
Melanocyte: specialized skin cell with the melanin pigment
Osteoclast: bone cell with multiple nuclei; helps with the absorption and dissolution of bone
Paracrine: denotes the secretion and binding of a hormone from one organ to another
Transcription factor: a protein that binds to a specific sequence of DNA, regulating the transcription of DNA into mRNA
Apoptosis: programmed cell death
Melanoblast: precursor of a melanocyte, originates in the neural crest
Neural crest: a group of embryonic cells that are not part of the CNS but migrate to and help form many parts of the nervous system
Sources: "Developmental Biology" Tenth edition - Scott F. Gilbert
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