S-adenosyl-L-methionine-dependent methyltransferase that has the ability to methylate both RNAs and proteins (Probable). Involved in pre-rRNA processing. Utilizes the methyl donor S-adenosyl-L-methionine to catalyze the site-specific 2'-hydroxyl methylation of ribose moieties in pre-ribosomal RNA (Probable). Site specificity is provided by a guide RNA that base pairs with the substrate (Probable). Methylation occurs at a characteristic distance from the sequence involved in base pairing with the guide RNA (Probable). Also acts as a protein methyltransferase by mediating methylation of 'Gln-105' of histone H2A (H2AQ105me), a modification that impairs binding of the FACT complex and is specifically present at 35S ribosomal DNA locus (By similarity). Binds monophosphate phosphoinositides in vitro (PubMed:29163603). a ribonucleotide in rRNA + S-adenosyl-L-methionine = a 2'-O-methylribonucleotide in rRNA + H(+) + S-adenosyl-L-homocysteine L-glutaminyl-[histone H2A] + S-adenosyl-L-methionine = H(+) + N(5)-methyl-L-glutaminyl-[histone H2A] + S-adenosyl-L-homocysteine Component of box C/D small nucleolar ribonucleoprotein (snoRNP) particles (By similarity). Interacts with SKP1A (PubMed:11387208). Localizes to the fibrillar region of the nucleolus. Expressed in roots, leaves and flowers (PubMed:10829025, PubMed:10806224). Expressed in stems (PubMed:10829025). Repressed by abscisic acid (ABA). The N-terminal DMA/Gly-rich region (also called GAR domain) is rich in Gly and Arg and functions in nucleolar targeting. Belongs to the methyltransferase superfamily. Fibrillarin family. Truncated N-terminus.