Lipocalin 9 (LCN9)

Lipocalin 9 (LCN9) is a member of the lipocalin protein family characterized by a conserved eight-stranded antiparallel beta-barrel structure (calyx) that binds and transports small hydrophobic molecules[1][2][4]. LCN9 is specifically expressed in the epididymis and, by analogy with related family members, likely plays a role in the transport of hydrophobic ligands relevant to sperm maturation and epididymal function[1][2]. The broader lipocalin family is involved in diverse biological functions, including reproduction, chemical communication, immunity, and metabolic regulation, but the precise physiological or pathological functions of LCN9 remain largely uncharacterized[1][3]. Diseases such as ophthalmia nodosa and tick infestation are associated with LCN9 at the gene annotation level, but direct mechanistic disease roles are not established[2]. Key points: - LCN9 is not currently a recognized therapeutic target and has no documented drugs or mechanisms of action directly related to it. - Roles established for other lipocalins, such as involvement in male fertility and hydrophobic ligand transport, are plausible for LCN9, but experimental confirmation is limited[1][2][3]. - There is no evidence of LCN9 serving as a clinical biomarker or possessing known therapeutic or safety concerns[1][2][3][4].

Other names

Epididymal-specific lipocalin-9MUP-like lipocalinEpididymis luminal protein 129 (HEL129)9230102I19Rik