EFNB1

The protein encoded by this gene is a type I membrane protein and a ligand of Eph-related receptor tyrosine kinases. It may play a role in cell adhesion and function in the development or maintenance of the nervous system.

Full Name

Ephrin B1

Research Area

Cell surface transmembrane ligand for Eph receptors, a family of receptor tyrosine kinases which are crucial for migration, repulsion and adhesion during neuronal, vascular and epithelial development (PubMed:8070404, PubMed:7973638).

Binding to Eph receptors residing on adjacent cells leads to contact-dependent bidirectional signaling into neighboring cells (PubMed:8070404, PubMed:7973638).

Shows high affinity for the receptor tyrosine kinase EPHB1/ELK (PubMed:8070404, PubMed:7973638).

Can also bind EPHB2 and EPHB3 (PubMed:8070404).

Binds to, and induces collapse of, commissural axons/growth cones in vitro (By similarity).

May play a role in constraining the orientation of longitudinally projecting axons (By similarity).

Biological Process

Axon guidance Source: GO_Central
Cell adhesion Source: ProtInc
Cell-cell signaling Source: ProtInc
Embryonic pattern specification Source: Ensembl
Ephrin receptor signaling pathway Source: GO_Central
Neural crest cell migration Source: Ensembl
Positive regulation of T cell proliferation Source: Ensembl
T cell costimulation Source: Ensembl

Cellular Location

Cell membrane; Membrane raft. May recruit GRIP1 and GRIP2 to membrane raft domains.
Ephrin-B1 C-terminal fragment: Cell membrane
Ephrin-B1 intracellular domain: Nucleus. Colocalizes with ZHX2 in the nucleus.

Involvement in disease

Craniofrontonasal syndrome (CFNS):
X-linked inherited syndrome characterized by hypertelorism, coronal synostosis with brachycephaly, downslanting palpebral fissures, clefting of the nasal tip, joint anomalies, longitudinally grooved fingernails and other digital anomalies.

Topology

Extracellular: 28-237
Helical: 238-258
Cytoplasmic: 259-346

PTM

Inducible phosphorylation of tyrosine residues in the cytoplasmic domain.
Proteolytically processed. The ectodomain is cleaved, probably by a metalloprotease, to produce a membrane-tethered C-terminal fragment. This fragment is then further processed by the gamma-secretase complex to yield a soluble intracellular domain peptide which can translocate to the nucleus. The intracellular domain peptide is highly labile suggesting that it is targeted for degradation by the proteasome.