Lipocalin 6 (LCN6)

Using database analysis and cDNA sequencing from a human caput library, Hamil et al. (2003) identified LCN6. The 163-amino acid LCN6 protein contains a predicted 20-amino acid signal peptide.human LCN6 is 93% identical to rhesus monkey Lcn6 and lacks a second, C-terminal cysteine found in many lipocalins. The LCN6 protein contains multiple phosphorylation sites, and structural prediction programs showed that LCN6 displays the characteristic lipocalin 3-dimensional structure. Northern blot analysis revealed robust expression of a 1-kb LCN6 transcript in epididymis. Using immunohistochemistry, strong expression of LCN6 protein in the caput epithelium and lumen; immunofluorescence of human spermatozoa showed strong LCN6 expression in large patches in the postacrosomal region of the head.