Methylcytosine-binding proteins containing SRA (SET- and RING-Associated) domain are required for the establishment and/or maintenance of DNA methylation in both plants and animals. We previously proposed that Arabidopsis VIM/ORTH proteins with an SRA domain maintain DNA methylation and epigenetic gene silencing in heterochromatic regions. However, their endogenous targets of epigenetic gene silencing have not been analyzed globally and the mechanisms by which VIM proteins coordinate DNA methylation and epigenetic silencing are largely unknown. In this study, a genome-wide transcript profiling analysis revealed 544 derepressed genes in a vim1/2/3 triple mutant, including 133 known genes. VIM1 bound to promoter and transcribed regions of the up-regulated genes in vim1/2/3 and VIM deficiency caused severe DNA hypomethylation in all sequence contexts at direct VIM1 targets. We found a drastic loss of H3K9me2 at heterochromatic chromocenters in vim1/2/3 nuclei. Furthermore, aberrant changes in transcriptionally active and repressive histone modifications were observed at VIM1 targets in vim1/2/3. VIM1-binding capacity to target genes was significantly reduced in the met1 background, indicating that VIM1 primarily recognizes CG methylation deposited by MET1. Overall, our data indicate that VIM proteins regulate genome-wide epigenetic gene silencing through coordinated modulation of DNA methylation and histone modification status in collaboration with MET1.

Background: Most women with systemic lupus erythematosus (SLE) are diagnosed with the disease in their reproductive years, but the incidence and prevalence of SLE among women of childbearing age have not been studied. The objective of this study was to estimate the incidence and prevalence of SLE among the Korean women of childbearing age. Methods: Women aged 20 to 44 years with SLE were identified from National Health Insurance Service – National Health Information Database (2009-2016), which contain health information of approximately 97% of the Korean population. SLE was defined by International Classification of Diseases, 10th revision code, M32. Incidence and prevalence were calculated per 100,000 person-years and stratified by year and age. Results: A total of 12,756 women with SLE were identified. The incidence of SLE from 2011 to 2016 among women in childbearing years was 8.18/100,000 person-years (95% CI 7.94–8.43), with the highest incidence in 2016 (8.56/100,000 person-years, 95% CI 7.95–9.17) and the lowest incidence in 2012 (7.85/100,000 person-years, 95% CI 7.28–8.42). The prevalence of SLE from 2009 to 2016 among women in childbearing years was 77.07/100,000 person-years (95% CI 75.76–78.39), with the highest prevalence in 2014 (79.47/100,000 person-years, 95% CI 77.64–81.30) and the lowest in 2010 (74.19/100,000 person-years, 95% CI 72.45–75.93). The peak age for SLE incidence was between 25–39 years, and lower incidence was seen in the early (20–24 years) and late (40–44 years) childbearing age periods. There was an increasing trend in prevalence according to age in women of childbearing age, with the highest prevalence occurring in the 40–44 age group. Conclusions: The risk and burden of SLE are high among women during their childbearing years. This calls for special attention to this particular population group when allocating health resources.

Periodontitis and rheumatoid arthritis (RA) are inflammatory diseases that share many similarities. We aimed to investigate the associations of periodontitis and oral hygiene status and behaviors with RA in a nationwide general population cohort. Participants from the National Health Screening cohort database of Korea who underwent oral health screening by dentists between 2003 and 2004 were included. The occurrence of RA was analyzed according to the presence of periodontitis, oral health examination findings, and behaviors. Overall, 2,239,586 participants were included. During a median of 16.7 years, RA occurred in 27,029 (1.2%) participants. The risk for incident RA was higher when participants had periodontitis (hazard ratio (HR) 1.2, 95% confidence interval (CI), 1.08−1.24) and an increased number of missing teeth (HR 1.5, 95% CI, 1.38−1.69). In contrast, better oral hygiene behaviors, such as a higher frequency of daily tooth brushing (HR 0.76, 95% CI 0.73–0.79, p for trend <0.001) and a recent history of dental scaling (HR 0.96, 95% CI 0.94–0.99), were associated with a lower occurrence of RA. Periodontitis and increased missing teeth were associated with an increased risk of RA. Maintaining good oral hygiene through frequent tooth brushing and regular dental scaling may reduce the risk of RA occurrence.