Immunogen sequence: PWDPGLTARD LLFRGGCRYR KRPRVVLDVT EQISRFLLDH GDVAFAPLGK LMLENFKLEG AGSRTKKKTV VSVKKLLQDL GGHQPWGCPW AYLSNRQRRF SILGGPILGT SVASHLAELL HEELVLRWEQ LLLDEACTGG ALAWVPG. Initiation of transcription by RNA polymerase I requires the formation