Phylogenetic analysis of FACT and SPT6 families of histone chaperones from diverse eukaryotic taxa. Phylogenetic trees were constructed to determine evolutionary distances among the members of each of the two sub-families of FACT family viz. SSRP (A), and SPT16 (B); and SPT6 family (C) from Arabidopsis thaliana (named by prefixing ‘At’), Oryza sativa (named by prefixing ‘Os’), Chlamydomonas reinhardtii (represented by the prefix ‘Cre’ with the locus id), Physcomitrella patens (represented by the prefix ‘Phpat’ with the locus id), Selaginella moellendorffii (named by prefixing ‘Sm’), Picea abies (named by prefixing ‘Pa’), Saccharomyces cerevisiae (named by prefixing ‘Sc’), and Homo sapiens (named by prefixing ‘Hs’). Protein sequences were aligned using ClustalX2 and the tree was constructed using MEGA 6.06 using Maximum Likelihood method and viewed using iTOL. Reliability of the branches was estimated using bootstrap analyses of 1000 replicates. Bootstrap values above 50% have been shown as numbers. Roman numerals show arbitrary numbers given to the phylogenetic groups with lower case letters showing sub-groups. Sequence ids of the proteins used for generation of the trees have been given in Table 1 (for Arabidopsis), Table 2 (for rice), and Additional file 2: Table S2 (for S. cerevisiae, and H. sapiens) and Additional file 3: Table S3 (for rest of the studied species).