SEMA4D
Description
The SEMA4D (semaphorin 4D) is a protein-coding gene located on chromosome 9.
Semaphorin-4D (SEMA4D), also known as Cluster of Differentiation 100 (CD100), is a protein belonging to the semaphorin family, encoded by the SEMA4D gene in humans. SEMA4D functions as an axon guidance molecule, secreted by oligodendrocytes, that induces growth cone collapse in the central nervous system. It binds to the plexin B1 receptor, acting as an R-Ras GTPase-activating protein (GAP), and repels axon growth cones in both the mature central nervous system. In the immune system, CD100 interacts with CD72 to activate B cells and dendritic cells, although the details of this interaction are still under investigation. During skin damage repair, SEMA4D interacts with Plexin B2 on Gamma delta T cells, playing a role in the healing process.
SEMA4D acts as a cell surface receptor for PLXNB1 and PLXNB2, playing a crucial role in cell-cell signaling. It regulates the development of GABAergic synapses, promoting the formation of inhibitory synapses in a PLXNB1-dependent manner. SEMA4D also influences the complexity and branching patterns of developing neurites in hippocampal neurons by activating PLXNB1, and its interaction with PLXNB1 triggers the activation of RHOA. Furthermore, SEMA4D promotes the migration of cerebellar granule cells and plays a significant role in the immune system by inducing B-cell aggregation and enhancing their viability in vitro. It also stimulates endothelial cell migration by activating PTK2B/PYK2, SRC, and the phosphatidylinositol 3-kinase-AKT pathway.
SEMA4D is also known as A8, BB18, C9orf164, CD100, COLL4, GR3, M-sema-G, SEMAJ, coll-4.
