Relaxin 3, Prorelaxin H3, RXN3, Insl7, ZINS4, H3, Relaxin 3 (H3), Relaxin-3, RLN3.
Relaxin-3 (RLN3), a member of the relaxin hormone family, exhibits both endocrine and autocrine/paracrine functions. Primarily recognized for its role in the reproductive system, relaxin, produced by the ovary, facilitates cervical ripening, pubic symphysis elongation, and uterine contraction inhibition in mammals. Deviating from Relaxins 1 and 2 in humans, RLN3 appears to have limited reproductive involvement but plays a crucial role in stress response within the brain stem. It specifically binds to the G-protein-coupled receptor GPCR135 (RXFP3) as its only known ligand. Although RLN3 exhibits binding affinity to the LGR7 (RXFP1) receptor, it is weaker compared to Relaxin-2. While RLN3 binding to LGR7 triggers intracellular cAMP increase, its interaction with GPCR135 suppresses cAMP accumulation, suggesting coupling to Gi, Go, or Gz by the receptor.
Relaxin 3, Prorelaxin H3, RXN3, Insl7, ZINS4, H3, Relaxin 3 (H3), Relaxin-3, RLN3.
Relaxin-3, also known as H3 relaxin or INSL7, is a member of the relaxin family of peptides, which are part of the insulin superfamily . Unlike human relaxins 1 and 2, which are primarily involved in reproductive processes, Relaxin-3 functions as a neuropeptide and plays a significant role in the central nervous system .
Relaxin-3 was discovered through homology searching of the human genome approximately 20 years ago . It is a disulfide-linked heterodimer composed of two chains: the A chain (Asp119-Cys142) and the B chain (Ala27-Arg53) . The predicted molecular masses of the A and B chains are 2.46 kDa and 3.04 kDa, respectively .
Relaxin-3 is primarily expressed in the brainstem and has been shown to modulate neuronal activity in multiple brain circuits . It interacts with its cognate G-protein-coupled receptor, relaxin-family peptide receptor 3 (RXFP3), to influence various neuroendocrine functions . This peptide is involved in stress response, feeding behavior, and arousal .
Recombinant human Relaxin-3 is produced using Escherichia coli (E. coli) expression systems . The protein is typically purified to a high degree of purity (>95%) and is free from endotoxins (<0.10 EU per 1 μg of protein) . The recombinant protein is often lyophilized and can be reconstituted in sterile phosphate-buffered saline (PBS) for use in various research applications .