Immunogen sequence: PNGDSSCNQG DYLVLRNGPD IYSPPLGPPG GNGHFCGSHA SSTLFTSDNQ MFVQFISDHS NEGQGFKIKY EAKSLACGGN VYIHDADSAG YVTSPNHPHN YPPHADCIWI LAAPPETRIQ LQFEDRFDIE VTPNCTSNYL. Cubilin (CUBN) acts as a receptor for intrinsic factor-vitamin B12 complexes. T