Undetectable levels of N6-methyl adenine in mouse DNA: Cloning and analysis of PRED28, a gene coding for a putative mammalian DNA adenine methyltransferase.
Three methylated bases, 5-methylcytosine, N4-methylcytosine and N6-methyladenine (m6A), can be found in DNA. However, to date, only 5-methylcytosine has been detected in mammalian genomes. To reinvestigate the presence of m6A in mammalian DNA, we used a highly sensitive method capable of detecting one N6-methyldeoxyadenosine per million nucleosides. Our results suggest that the total mouse genome contains, if any, less than 10(3) m6A. Experiments were next performed on PRED28, a putative mammalian N6-DNA methyltransferase. The murine PRED28 encodes two alternatively spliced RNA. However, although recombinant PRED28 proteins are found in the nucleus, no evidence for an adenine-methyltransferase activity was detected.
Ratel
David
D
INSERM U318, UJFG, CHU Michallon, 38043 Grenoble, France.
Ravanat
Jean-Luc
JL
Charles
Marie-Pierre
MP
Platet
Nadine
N
Breuillaud
Lionel
L
Lunardi
Joël
J
Berger
François
F
Wion
Didier
D