Abstract

DNA methylation plays a vital role during development in gene expression and chromatin organization. DNA methyl transferases catalyze the transfer of a methyl group to bases within the DNA helix. Plants differ from animals in having methylation at the sites of CHG and CHH. In plant, there are at least four classes of cytosine methyltransferase: MET1, CMT3, DRM and DNMT2. They show distinct expression patterns and levels in tissues and developmental stages and differential activity on cytosines in different sequence contexts. Mutations that cause severe loss of DNA methylation often leads to abnormal development. In the present review, we summarized recent findings of the three major DNA methyltransferases mutants playing vital role in development of Arabidopsis thaliana.

Key words: DNA methylation, epigenetics, methyltransferase, mutant.

Abbreviation

Abbreviations: CMT3, Chromomethyltransferases 3; DDM1, decrease in DNA methylation 1; DNMT1, DNA methyltransferase 1; DNMT2, DNA methyltransferase 2; DNMT3a, DNA methyltransferase 3a; DNMT3b, DNA methyltransferase 3b;DNMT3L, DNA methyltransferase 3L; DME, demeter; DML, demeter-like proteins;DRM, domains rearranged methyltransferases; H3K9, Histone H3 lysine 9; H3K27,histone H3 lysine 27; H3K9me2, histone H3 dimethylation at lysine 9; H3K27me3,trimethylated lys 27 of histone 3; HMTase, histone methyltransferase; ibm1,increase in bonsai methylation 1; LTR, Long terminal repeat; m5C, C5-methylcytosine; MET1, methyltransferases1; MEA, medea; MTase,methyltransferase; PAI, phorphosibosyl-anthranilate-isomerase; RdDM, RNA-directed DNA methylation; RRD2, RNA-dependent tRNA polymerase; ROS1,repressor of silencing 1; SET, histone methyltransferase; SDC, suppressor of drm1/2 cmt3; siRNA, small interfering RNA; SUP, superman; SUVH4, su(var)3-9 homolog 4; TRDMT1, tRNA aspartic acid methyltransferase 1; TGS, transcriptional gene silencing; UBA, ubiquitin associated.