Fig. 4. Characterization of FER-1 protein isoforms. (A) Affinity purified polyclonal anti-DysfNC antibody recognizes three proteins in whole males (wt), which are absent in the stop codon mutant fer-1(hc47). Protein from 250 virginized male worms/lane. (B) Anti-DysfNC western blot of him-5 whole male (), fem-1 (spermless) hermaphrodites (), and fem-3(q20) purified spermatid (sp) protein extracts. Numbers on right indicate calculated molecular masses, in kDa. (C) Distribution of peptides identified by mass spectrometry from 195 and 180 kDa bands depicted along full-length FER-1 protein (images generated by Tandem at http://www.thegpm.org). Peptides are listed in supplementary material Table S2.