Unusual histone H2A variants of the bdelloid species Adineta vaga (Av) and Philodina roseola (Pr).

(A) All three bdelloid H2A variants (H2Abd, H2Abd1 and H2Abd2), with their respective name code for each copy, are given. Each copy of the histone gene cluster is also represented, being organized as co-linear pairs A and B. Presented in light grey boxes are genes likely present in the nucleosomes; dark grey boxes represent expressed variants found in the bdelloid proteome (see below); white boxes represent unknown expression status. (B) Multiple alignment using MAFFT v6 of the histone H2A genes of the bdelloid species Av and Pr and the monogonont rotifer Brachionus plicatilis (Bp) with canonical H2A, H2AX and H2AZ variants of few other model eukaryotes. Red, blue and yellow boxes indicate the bdelloid H2Abd, H2Abd1 and H2Abd2 genes, respectively. The red arrow indicates the start of the C-terminal tail beyond the conserved LLPKK motif. Protein interaction domains (“loop1” and “docking”) are indicated and taken from [37]. The regions of primer design are in a dashed box and the light grey boxes represent the regions where H2AZ differs substantially from canonical H2A.