csp-1 mRNA was not detectable in the somatic cells of wild-type embryos, larvae or adult hermaphrodites.
csp-1 transcripts were present in the germlines of L4-stage larval and adult hermaphrodites. This expression was restricted to the late pachytene stage of meiosis I in both L4 larval gonads (in pachytene nuclei adjacent to differentiating sperm) and adult gonads (in pachytene nuclei adjacent to the bend of the gonad arm). Both
csp-1A and csp- 1B/C transcripts were expressed in the adult pachytene germ cells, as indicated by the presence of FISH foci recognized by the
csp-1A prodomain probes and foci recognized primarily by the
csp-1B probes and only weakly by the
csp-1A probes.