Figure 1.
A schematic diagram of the imprinted snoRNA gene cluster in the PWS-related imprinted locus.
The top panel depicts the gene distribution across the entire PWS locus. Pink represents maternally expressed genes, blue represents paternally expressed genes, red represents imprinted snoRNA clusters, and the dashed wavy line represents non-coding transcripts. In the lower panels, each snoRNA gene is represented by a vertical bar. The distribution of snoRNA genes was scaled to their genomic location, and the colors indicate their respective gene families. Clusters are scaled relative to their size within the chromosome.
Table 1.
Statistics of imprinted snoRNA genes in the PWS locus of mammalians.
Figure 2.
Phylogenetic analysis of HBII-52 and HBII-85 gene family.
Abbreviations: HS, human; PT, chimpanzee; RM, rhesus; MM, mouse; RN, rat; CF, dog; FC, cat; EC, horse; BT, cow; DN, armadillo; LA, elephant.
Figure 3.
Gene numbers and changes in PWS-related imprinted snoRNA genes with respect to eutherian divergence.
Numbers in black indicate the current gene number in each species, whereas red numbers indicate the ancestral gene number, blue numbers denote gained genes, and green numbers indicate lost genes. The major diversification events of eutherians are indicated on the timescale. MYA, a million years ago.
Table 2.
Birth rates of new genes among PWS-related imprinted and non-imprinted snoRNAs.
Figure 4.
Evolutionary divergence of PWS-related imprinted vs. non-imprinted snoRNA gene families between the human and other mammals.
(A) The evolutionary divergence of HBII-52, HBII-85, non-imprinted guide and orphan snoRNA genes between human and other species. K denotes the number of substitutions per site. (B) Relative sequence substitution rate between imprinted and non-imprinted snoRNA genes of eutherian mammals.
Table 3.
Genetic divergence of snoRNA genes and their flanking sequences in primates for both imprinted and non-imprinted snoRNAs.
Figure 5.
Evolutionary divergence rates for each part of the imprinted snoRNA genes between the human and other mammals.
A diagram of box C/D snoRNA structure with different partitions was illustrated in the left [modified from 25]. K denotes the number of substitutions per site. Each color represents a comparison between human and another species.
Table 4.
Tajima’s D test of Euarchontoglires imprinted snoRNA gene family.
Table 5.
Ka/Ks tests of protein-coding genes in the PWS locus.
Figure 6.
The binding pattern between HBII-52 and 5-HT2CR mRNA in mammals.
(A) Left panels indicate the length distribution of perfect base-pairing between HBII-52 and 5-HT2CR mRNA. Right panels indicate the distance of base-pairing from the D box motif. Analyses of primates, rodents and other mammals are indicated with different colors. In primates and rodents, the length of the base-pairing was centered approximately 18 nt and started just upstream of the D box. In other species, the length of the base-pairing ranged from 9–14 nt and started several nucleotides away from the D box. (B) The best base complementarity between the antisense element of the human, elephant or horse HBII-52 snoRNA and the corresponding 5-HT2CR receptor. Nucleotides in red indicate the A to I editing sites (A to E); nucleotides in orange indicate proximal splice site. Box, D box. Red crosses indicate mismatch within the RNA duplex.
Figure 7.
Evolutionary divergence of imprinted 14q(I) and 14q(II) snoRNA family vs. non-imprinted snoRNA gene families between the human and other mammals.
K denotes the number of substitutions per site.
Figure 8.
Evolutionary divergence rates for each part of the imprinted snoRNA genes in 14q32 region between the human and other mammals.