urum wheat (DW), Triticum turgidum L. ssp. durum (Desf.) Husn., genome BBAA, is a cereal grain mainly used for pasta production and evolved from domesticated emmer wheat (DEW), T. turgidum ssp. dicoccum (Schrank ex Schübl.) Thell. DEW itself derived from wild emmer wheat (WEW), T. turgidum ssp. dicoccoides (Körn. ex Asch. & Graebn.

The present work investigates the occurrence and significance of aberrant DNA methylation patterns during early stages of atherosclerosis. To this end, we asked whether the genetically atherosclerosis-prone APOEnull mice show any changes in DNA methylation patterns before the appearance of histologically detectable vascular lesion. We exploited a combination of various techniques: DNA fingerprinting, in vitro methyl-accepting assay, 5-methylcytosine quantitation, histone posttranslational modification analysis, Southern blotting, and PCR. Our results show that alterations in DNA methylation profiles, including both hyper-and hypomethylation, were present in aortas and PBMC of 4-week-old mutant mice with no detectable atherosclerotic lesion. Sequencing and expression analysis of 60 leukocytic polymorphisms revealed that epigenetic changes involve transcribed genic sequences, as well as repeated interspersed elements. Furthermore, we showed for the first time that atherogenic lipoproteins promote global DNA hypermethylation in a human monocyte cell line. Taken together, our results unequivocally show that alterations in DNA methylation profiles are early markers of atherosclerosis in a mouse model and may play a causative role in atherogenesis.Atherosclerosis and its complications are a major cause of death and disability in the developed world. The disease is characterized by infiltration of lipid particles in the arterial wall, accompanied by the recruitment of inflammatory and immune cells, migration and proliferation of smooth muscle cells (SMC), 1 and synthesis of extracellular matrix. These processes eventually result in the gradual development of an elevated lipid-rich, fibrocellular lesion (1).In mammals, DNA methyltransferases use S-adenosyl methionine (SAM) as a methyl group donor to methylate the carbon in position 5 of cytosine residues in a CpG dinucleotide (CG) context (2). DNA methylation regulates fundamental biological phenomena such as gene expression, genome stability, mutation rate, genomic imprinting, and X chromosome inactivation (3-6). Both global and gene-specific alterations in DNA methylation are associated with abnormal phenotypes in disease (7,8). For example, cancer cells show global genomic hypomethylation and dense hypermethylation of CpG islands, which are normally unmethylated (9). The identification of cancer type-and stage-specific changes in DNA methylation has justified hopes for novel diagnostic and therapeutic avenues (10).Two general observations suggest that alterations in DNA methylation patterns are involved in atherogenesis (11-13). First, global hypomethylation and dense hypermethylation of certain CpG islands are associated with aging, a major risk factor for atherosclerosis (14). Second, hyperhomocysteinemia and the subsequent decreased production or bioavailability of SAM is associated with an increased risk of cardiovascular disease (15). Accordingly, mice with genetically reduced levels of methylenetetrahydrofolate reductase, a key enzyme in the pathway generating ...

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A PCR-based genomic scan has been undertaken to estimate the extent and ratio of maternally versus paternally methylated DNA regions in endosperm, embryo, and leaf of Zea mays (maize). Analysis of several inbred lines and their reciprocal crosses identified a large number of conserved, differentially methylated DNA regions (DMRs) that were specific to the endosperm. DMRs were hypomethylated at specific methylation-sensitive restriction sites upon maternal transmission, whereas upon paternal transmission, the methylation levels were similar to those observed in embryo and leaf. Maternal hypomethylation was extensive and offers a likely explanation for the 13% reduction in methyl-cytosine content of the endosperm compared with leaf tissue. DMRs showed identity to expressed genic regions, were observed early after fertilization, and maintained at a later stage of endosperm development. The implications of extensive maternal hypomethylation with respect to endosperm development and epigenetic reprogramming will be discussed.