Comparative depiction of the KRAB domain sequences of ZNF10, XFIN, PRDM7 and PRDM9.

Alignment of KRAB-A (A) or KRAB-B (B) subdomains and comparison to the respective human and frog HMM models. The sequences were derived from NCBI Refseq database entries for human ZNF10/Kox1 (ZNF10; NP_056209), Xenopus laevis XFIN (XFIN-ref; NP_001095247), human PRDM7 (NP_001091643) and human PRDM9 (NP_064612). The corrected XFIN-A sequences were derived by in-silico translation from GenBank EU277665 (labeled XFIN-A corr; see text for details). Brackets with an asterisk denote amino acid groups whose mutation have been shown to disrupt transcriptional repression, whereas those with open circle denote positions where mutation had not much effect [11]. Arrowheads point to amino acids that might be responsible for observed functional differences (see text). The right arrow marks the methionine that has been considered the start of the XFIN protein in the database reference sequence. The consensus reflects amino acids in at least 60% of the molecules at each position. HMMER scores against respective human or Xenopus HMM matrices are given to the right of each sequence. The HMM matrices are visualized as HMM-Logos [57] at the bottom of each sub-figure. Note, that the amino acid positions in the logo are aligned with the ones in the sequence alignments.