Recombinant Human KIRREL3 / NEPH2 protein

KIRREL3 (kin of IRRE-like 3), also known as NEPH2 or FILTRIN, is a transmembrane protein belonging to the immunoglobulin superfamily. It is part of the nephrin-like protein family, which includes structurally similar molecules involved in cell adhesion and signaling. KIRREL3 is characterized by extracellular immunoglobulin-like domains, a single transmembrane region, and a cytoplasmic tail with signaling motifs. It plays critical roles in cell-cell recognition and adhesion processes, particularly in the nervous system and kidneys. In the brain, KIRREL3 is implicated in synapse formation and maintenance, interacting with presynaptic partners like presynaptic cell adhesion molecules to regulate neuronal connectivity. It also contributes to the Slit-Robo signaling pathway, influencing axon guidance and neural circuit development.

In renal physiology, KIRREL3 localizes to podocyte foot processes in the glomerulus, where it interacts with nephrin and SDCCAG1 to maintain the kidney’s filtration barrier. Mutations or dysregulation of KIRREL3 have been associated with neurodevelopmental disorders, including autism spectrum disorders, intellectual disability, and speech delays, as well as renal pathologies like nephrotic syndrome. Recombinant KIRREL3/NEPH2 proteins are engineered to study these biological functions, typically produced in mammalian or bacterial expression systems. These purified proteins enable in vitro investigations into binding partners, structural interactions, and signaling mechanisms. Researchers utilize them in assays to decipher KIRREL3’s role in synaptic plasticity, cell adhesion dynamics, and disease pathways, offering insights into potential therapeutic targets for neurological and renal conditions. The protein’s dual involvement in neural and renal systems underscores its biological significance across multiple organ systems.