DNA adenine methylation changes dramatically during establishment of symbiosis.
The DNA adenine methylation status on specific 5'-GANTC-3' sites and its change during the establishment of plant-microbe interactions was demonstrated in several species of alpha-proteobacteria. Restriction landmark genome scanning (RLGS), which is a high-resolution two dimensional DNA electrophoresis method, was used to monitor the genomewide change in methylation. In the case of Mesorhizobium loti MAFF303099, real RLGS images obtained with the restriction enzyme MboI, which digests at GATC sites, almost perfectly matched the virtual RLGS images generated based on genome sequences. However, only a few spots were observed when the restriction enzyme HinfI was used, suggesting that most GANTC (HinfI) sites were tightly methylated and specific sites were unmethylated. DNA gel blot analysis with the cloned specifically unmethylated regions (SUMs) showed that some SUMs were methylated differentially in bacteroids compared to free-living bacteria. SUMs have also been identified in other symbiotic and parasitic bacteria. These results suggest that DNA adenine methylation may contribute to the establishment and/or maintenance of symbiotic and parasitic relationships.
Ichida
Hiroyuki
H
Graduate School of Science and Technology, Chiba University, Matsudo, Japan. ichida@riken.jp
Matsuyama
Tomoki
T
Abe
Tomoko
T
Koba
Takato
T
D000225:Adenine / Q000378:metabolism*; D020561:Alphaproteobacteria / Q000145:classification / Q000378:metabolism; D019175:DNA Methylation; D004269:DNA, Bacterial / Q000378:metabolism*; D018744:DNA, Plant / Q000378:metabolism; D015252:Deoxyribonucleases, Type II Site-Specific / Q000378:metabolism; D015180:Electrophoresis, Gel, Two-Dimensional; D016680:Genome, Bacterial / Q000502:physiology; D000070116:Lotus / Q000378:metabolism; D013559:Symbiosis / Q000235:genetics* / Q000502:physiology
D004269:DNA, Bacterial; D018744:DNA, Plant; D015252:Deoxyribonucleases, Type II Site-Specific; C032229:GANTC-specific type II deoxyribonucleases; C024405:GATC-specific type II deoxyribonucleases; D000225:Adenine