Immunogen sequence: SLEHVLHFIT IFTGSIERMK NPHLRAKLAE VLEAVMPHLD QTPNPLVSSV FHRKRVFCNF QYAPQLAEAL IKVFVDIEFT GDPHQFEQKF. Ubiquitination requires a ubiquitin-activating enzyme, a ubiquitin-conjugating enzyme, and usually a substrate-specific ubiquitin-prot