Catalysis of the reaction: S-adenosyl-L-methionine + adenine(645) in 25S rRNA = S-adenosyl-L-homocysteine + N(1)-methyladenine(645) in 25S rRNA.
Source:EC:2.1.1.287,
PMID:23180764
Comment
The m(1)A modification at position 645 in the large rRNA is highly conserved in eukaryotes.