What is kit ligand?

Question

What is kit ligand?

Answer 1

KIT ligand is a cytokine (a type of signalling protein that is made by a variety of cell types and allows for certain kinds of cellular communication).  It is also sometimes called stem cell factor (SCF), because one of its actions is as a growth factor for hematopoietic stem cells (the ones that develop into blood cells).  It can be found either on cell surfaces or in soluble form in the blood.

"Ligand" means it binds something in order to work, and in this case what it binds is called (logically enough) KIT or also sometimes called CD117 or c-KIT receptor.  CD means "cluster of differentiation" and anything that is called CD-anything is a cell surface marker that may be used for recognition, for signalling, or to identify the cell's activity.

The system is notable because KIT is what is called a proto-oncogene, meaning that disruptions in its pathway, like overexpression or mutations, can lead to certain kinds of cancers.

Answer 2

Kit ligand  is a pleiotropic growth factor that exerts an influence on target cells through binding the tyrosine kinase receptor, KIT. KITL and KIT are expressed by a variety of developmentally distinct cell lineages during both embryogenesis and adult life, and roles for KITL and KIT in gametogenesis, melanogenesis, and hematopoiesis have been described [1–3].