Mammalian TEKT family proteins form a range of complexes. (A) Silver-stained gel of TEKT3 and control immunoprecipitated (IP) samples from mouse testis extracts. Individual lanes were excised and analyzed by mass spectrometry. (B) The expression of TEKT4 and TEKT5 in spermatozoa was assessed by western blotting. β-Actin was used as a control for normalization. (C) Human TEKTINs were co-expressed in HEK293T cells, with co-IP used to detect interactions between TEKT3 and other members of the protein family.