Extended Data Fig. 2: Mass spectrometric analysis of the purified CatSpermasome.

a, MS samples were the same as used for the cryo-EM study. MS detected proteins are shown in order of decreasing confidence. All previously characterized CatSper components are listed (yellow). The top six entries with highest peptide spectrum match (PSM) values are all CATSPER proteins. Most of the contaminating proteins are cytoskeletal proteins. The newly identified components SLCO6C1 and CATSPERη are highlighted in red. TMEM249, which is probably another new component, is shaded in light blue. b, Representative MS spectra for specific peptides of CATSPER1, SLCO6C1, CATSPERη, and TMEM249.