Figure 7

Variation in the numbers of zinc finger motifs in mammals and in the presence of conserved N-terminal domains in orthologs. A) The average number of zinc finger motifs was calculated for all the C2H2-ZNF genes from the 81 human clusters identified and their corresponding syntenically homologous clusters in the other mammals. For each species, the average number of zinc finger motifs for the total C2H2-ZNF genes (All) and for members of the various C2H2-ZNF sub-families is presented. For each category, the number of genes in each species is listed above the bars in the following order (human, chimpanzee, mouse, rat and dog). B) For the human C2H2-ZNF cluster 6.2 (chromosome 6p22.1) and its syntenically homologous counterparts in chimpanzee, mouse, rat and dog, each C2H2-ZNF genes is represented by an open arrow which indicates its orientation on the chromosome strands; this excludes the pseudogenes whose names appear in parenthesis. For these clusters which contain C2H2-ZNF genes that are from the KRAB or SCAN subfamily or that do not encode any conserved N-terminal domain, the presence of a conserved N-terminal is indicated by as square for a KRAB domain or an open circle for a SCAN domain both being positioned in front of the open arrow representing the gene. Genes identified as orthologs, based on the phylogenetic tree and physical maps, are aligned vertically on their respective chromosomes. Cases where orthologs from the different mammals do not consistently share the same effector domain (s) are marked by a grey box. C) Exon-Intron organization of most human C2H2-ZNF genes from the SCAN-KRAB and SCAN subfamilies. 80% of SCAN-KRAB (11/14) and 55% of the SCAN (16/29) C2H2-ZNF genes found in clusters in human have the presented exon-intron structures shown. The exons encoding the SCAN, KRAB (A box) and ZNF are indicated.