PCOTH GI:62234340 prostate collagen triple helix isoform 1 1 mwilsnlmgt seegnllstv sptvkalfgk trvspifpfs prspfqplip 50 51 rtpgspwgpv gpasplgpgf pigpmgpgkp vgpkgpmlpl gpsgpvgpts 100 101 plfpfcp