FLRT3
Description
The FLRT3 (fibronectin leucine rich transmembrane protein 3) is a protein-coding gene located on chromosome 20.
Leucine-rich repeat transmembrane protein FLRT3 is a protein that in humans is encoded by the FLRT3 gene. FLRT1, FLRT2 and FLRT3 are members of the fibronectin leucine rich transmembrane protein (FLRT) family. They may function in cell adhesion and/or receptor signalling. Their protein structures resemble small leucine-rich proteoglycans found in the extracellular matrix. FLRT3 shares 55% amino acid sequence identity with FLRT1 and 44% identity with FLRT2. FLRT3 is expressed in kidney, brain, pancreas, skeletal muscle, lung, liver, placenta, and heart. Two alternatively spliced transcript variants encoding the same protein have been described for this gene.
FLRT3 plays a role in cell-cell adhesion, cell migration and axon guidance, exhibiting either attractive or repulsive effects depending on its interacting partners. It contributes to the spatial organization of brain neurons and vascular development in the retina. FLRT3 interacts with ADGRL3 and likely other latrophilins on adjacent cells, facilitating cell-cell adhesion. Its interaction with ROBO1's intracellular domain promotes axon attraction towards cells expressing NTN1. Conversely, FLRT3's interaction with UNC5B, and potentially other UNC-5 family members, leads to axon growth cone collapse and repulsion in neuron guidance. In vitro studies indicate that FLRT3 promotes neurite outgrowth. This protein mediates cell-cell contacts, enhancing both neurite number and length. FLRT3 contributes to the regulation of glutamaergic synapse density and participates in fibroblast growth factor-mediated signaling cascades. While essential for normal morphogenesis during embryonic development, FLRT3 is not required for normal embryonic patterning. It is crucial for proper ventral closure, headfold fusion, and definitive endoderm migration during embryonic development. Furthermore, FLRT3 is essential for the formation of a normal basement membrane and the maintenance of a normal anterior visceral endoderm during embryonic development.
FLRT3 is also known as HH21.
