Disease relevance of AT4G25730

• Overexpressing MMT from Arabidopsis in Escherichia coli, which is not known to have MMT activity, produced up to 10 times more volatile Se than the untransformed strain when both were supplied with Se-Met [1].
• Novel protein kinase interacts with the Cucumber mosaic virus 1a methyltransferase domain [2].
• An upstream region from an algal virus methyltransferase gene was tested for promoter function in transgenic plants, electroporated monocot protoplasts and bacteria [3].

High impact information on AT4G25730

• A transgenic Arabidopsis line carrying an antisense methyltransferase gene, which shows an overall decrease in genomic cytosine methylation, also contains a hypermethylated sup allele [4].
• The function of DNA methylation in higher plants was investigated by expression of a complementary DNA encoding a cytosine methyltransferase (MET1) from Arabidopsis thaliana as an antisense RNA in transgenic plants [5].
• Knock-out of the Magnesium Protoporphyrin IX Methyltransferase Gene in Arabidopsis: EFFECTS ON CHLOROPLAST DEVELOPMENT AND ON CHLOROPLAST-TO-NUCLEUS SIGNALING [6].
• Are there two DNA methyltransferase gene families in plant cells? A new potential methyltransferase gene isolated from an Arabidopsis thaliana genomic library [7].
• Using the 1kb 3' terminal DNA fragment of the mouse methyltransferase cDNA as a probe and low stringent hybridisation conditions, a new potential methyltransferase (MTase) gene family was isolated from an Arabidopsis thaliana genomic DNA library [7].

Biological context of AT4G25730

• Locus-Specific Control of DNA Methylation by the Arabidopsis SUVH5 Histone Methyltransferase [8].
• Thus, our results provide in vivo evidence that MMT is the key enzyme catalyzing the methylation of Se-Met to SeMM [1].
• This appears to be a general feature of angiosperms, as digital gene expression profiles show that MMT and HMT are co-expressed in leaves, roots and reproductive tissues of maize and other species [9].
• Both mutant alleles are disrupted structurally in the MET1 catalytic domain, suggesting that they are complete loss of function alleles [10].
• We discuss MET1 as a site-specific DNA methyltransferase that is able to maintain CG methylation during DNA replication and contribute to CG de novo methylation in response to RNA signals [10].

Anatomical context of AT4G25730

• A transgenic tobacco cell line that expressed the methyltransferase enzyme and carried an Arabidopsis cab3 gene containing a single target site for the adenine methyltransferase enzyme showed that the adenine residue was not methylated [11].

Associations of AT4G25730 with chemical compounds

• MMT and HMT together have been proposed to constitute a futile SMM cycle that stops the free Met pool from being depleted by an overshoot in AdoMet synthesis [9].
• SMM can be reconverted to Met by donating a methyl group to homocysteine (homo-Cys), and concurrent operation of this reaction and that mediated by MMT sets up the SMM cycle [12].
• The role of MET1 in RNA-directed de novo and maintenance methylation of CG dinucleotides [10].
• We have identified a putative abscisic acid-response element (ABRE) in the 5'-untranslated region of the A. thaliana L-isoaspartyl methyltransferase gene and have shown that the expression of the mRNA is responsive to exogenous abscisic acid (ABA), but not to the environmental stresses of salt or drought [13].

Analytical, diagnostic and therapeutic context of AT4G25730

• A plant cytosine methyltransferase cDNA was isolated using degenerate oligonucleotides, based on homology between prokaryote and mouse methyltransferases, and PCR to amplify a short fragment of a methyltransferase gene [14].

References