EFNA5
EFNA5 (ephrin A5, also known as AF1, LERK7 or EPLG7) is a GPI-anchored cell surface ligand for Eph receptors. By binding receptors on neighbouring cells, it drives contact-dependent signalling that shapes neuronal, vascular and epithelial development. Browse Assay Genie's current range of EFNA5 research reagents below, or read on for the biology behind the target.
EFNA5 is a cell surface ligand for Eph receptors, a family of receptor tyrosine kinases that are crucial for migration, repulsion and adhesion during neuronal, vascular and epithelial development. It binds Eph receptors promiscuously on adjacent cells and triggers contact-dependent bidirectional signalling. Signalling downstream of the receptor is called forward signalling, while signalling downstream of the ephrin ligand is called reverse signalling. When bound to the extracellular domain of its cognate receptor, EFNA5 induces compartmentalised signalling within a caveolae-like membrane microdomain, a step that requires the Fyn tyrosine kinase.
Functionally, EFNA5 activates the EPHA3 receptor to regulate cell-cell adhesion and cytoskeletal organisation. Together with EPHA2 it may regulate the shape and interactions of lens fibre cells and help maintain lens transparency. It is the cognate ligand for EPHA7, and this interaction regulates brain development by modulating cell-cell adhesion and repulsion. Its interaction with EPHA5 also mediates communication between pancreatic islet cells to regulate glucose-stimulated insulin secretion. It may actively stimulate axon fasciculation, although NCBI notes that ephrin-A5 prevents axon bundling in cocultures of cortical neurons with astrocytes, a model of late-stage nervous system development and differentiation.
The EFNA5 gene belongs to the ephrin family, which is divided into the GPI-anchored ephrin-A (EFNA) class and the transmembrane ephrin-B (EFNB) class. Eph receptors are likewise split into two groups according to extracellular domain similarity and their affinity for ephrin-A or ephrin-B ligands. Ephrins and their receptors were named by the Eph Nomenclature Committee in 1997. The mouse and rat orthologues are both called Efna5.
EFNA5 influences axon fasciculation and bundling and regulates brain development through EPHA7, making it a common subject in studies of neural wiring.
Forward and reverse signalling, including Fyn-dependent caveolae-like microdomain signalling, make EFNA5 a model ligand for studying contact-dependent communication.
EFNA5 activates EPHA3 to regulate cell-cell adhesion and cytoskeletal organisation, relevant to repulsion and adhesion during tissue development.
With EPHA2 it may support lens transparency, and via EPHA5 it mediates islet cell communication governing glucose-stimulated insulin secretion.
EFNA5 is a GPI-anchored ligand that binds Eph receptors on adjacent cells and triggers bidirectional signalling. It regulates cell adhesion and repulsion, cytoskeletal organisation, brain development via EPHA7, and islet cell communication affecting glucose-stimulated insulin secretion via EPHA5.
EFNA5 is the HGNC symbol for ephrin A5, also written ephrin-A5. Aliases and previous symbols include AF1, LERK7 and EPLG7. It sits in the HGNC ephrins gene group and belongs to the ephrin-A class of GPI-linked ligands.
Yes. Both mouse and rat have an orthologue named Efna5, which allows the ligand to be studied in rodent models of development. Always check the datasheet of any product for its validated reactivity.
Other ephrin-A ligands that, like EFNA5, bind Eph receptors on neighbouring cells.
Gene and protein annotations from HGNC, NCBI Gene and UniProt P52803; product specifications from Assay Genie datasheets.