RESUMO
A protein specifically binding a symmetrically methylated DNA fragment of the first intron of the mts1 gene was studied. The protein was purified by gel filtration and affinity chromatography. Mass spectrometry showed that the protein is Kaiso, a new member of the BTB/POZ family. To study the association with methylated DNA sequences in vivo, the location of Kaiso in NIH 3T3 cells was analyzed. Immunofluorescent staining with polyclonal antibodies against Kaiso showed that the protein is predominantly associated with the nucleoli. The causes of its distribution awaits further investigation. The zinc-finger domains of Kaiso were for the first time demonstrated to specifically recognize symmetrically methylated DNA sequences in vitro.
Assuntos
Nucléolo Celular/metabolismo , Metilação de DNA , Fatores de Transcrição/metabolismo , Células 3T3 , Animais , Nucléolo Celular/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Genes p16 , Humanos , Íntrons/genética , Camundongos , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Ligação Proteica , Fatores de Transcrição/genética , Dedos de ZincoRESUMO
Methylation is a modification that changes the structure and functional status of DNA. Hence it is interesting to study the effect of methylation on basic processes occurring in living cells. In this review, the role of DNA methylation in recombination, replication, transcription regulation, imprinting, tumorigenesis, and tumor progression is considered.