Project description:In the past few decades, the prevalence of overweight and obesity has sharply increased in children and adolescents. Childhood obesity life are associated with increased risk of cardiovascular disease (CVD), diabetes mellitus, metabolic syndrome, sleep disturbances and certain cancers in adulthood. Childhood obesity has become a serious global public health challenge. Long noncoding RNAs (lncRNAs) have an important role in adipose tissue function and energy metabolism homeostasis, and abnormalities may lead to obesity. We used microarrays to detail the differential expression profile of lncRNAs and mRNAs in obese children compared with non-obese children.
Project description:DNA methylation predominantly occurs at CG dinucleotides in vertebrate genomes, however, non-CG methylation (mCH) is also detectable in vertebrate tissues, most notably in the nervous system. In mammalian brains, it is well established that: i) mCH is targeted to CAC trinucleotides by DNMT3A, ii) enriched in gene bodies and repetitive elements, and iii) associated with transcriptional repression. However, the possible conservation of these mCH features in zebrafish is largely unexplored and has yet to be functionally demonstrated. In this study, we analyse the transcriptomes (RNA-seq) and methylome (RRBS) of developing zebrafish larvae (1-6 weeks) and adult brain (6 month). We additionally elucidate a role for dnmt3aa/dnmt3ab in mCH deposition via CRISP/CAS9 KO and WGBS of 4 week old brains
Project description:The postnatal neurodevelopmental disorder Rett syndrome (RTT) is caused by mutations in the gene encoding Methyl-CpG-binding Protein 2 (MeCP2). Despite decades of research, it remains unclear how MeCP2 actually regulates transcription or why RTT features appear only 6-18 months after birth. We examined MeCP2 binding to methylated cytosine in the CH context (mCH, where H = A, C, or T) in the adult mouse brain and found that MeCP2 binds these mCH sites, influencing nucleosome positioning and transcription. Strikingly, this pattern is unique to the mature nervous system, as it requires the increase in mCH after birth to reveal differences in MeCP2 binding to mCG, mCH, and non-methylated DNA elements. This study provides insight into the molecular mechanism governing MeCP2 targeting and how this targeting might contribute to the delayed onset of RTT symptoms. MeCP2 ChIP-Seq were conducted from ~ 7-week-old hypothalamus tissues from Mecp2-/y; MECP2-EGFP mice.
Project description:The postnatal neurodevelopmental disorder Rett syndrome (RTT) is caused by mutations in the gene encoding Methyl-CpG-binding Protein 2 (MeCP2). Despite decades of research, it remains unclear how MeCP2 actually regulates transcription or why RTT features appear only 6-18 months after birth. We examined MeCP2 binding to methylated cytosine in the CH context (mCH, where H = A, C, or T) in the adult mouse brain and found that MeCP2 binds these mCH sites, influencing nucleosome positioning and transcription. Strikingly, this pattern is unique to the mature nervous system, as it requires the increase in mCH after birth to reveal differences in MeCP2 binding to mCG, mCH, and non-methylated DNA elements. This study provides insight into the molecular mechanism governing MeCP2 targeting and how this targeting might contribute to the delayed onset of RTT symptoms. Mnase-Seq were conducted from 7-week-old hypothalamus from MeCP2 knockout mice and their age and genetic background matched wild types control mice.
Project description:This is a study of 114 newborns aimed at identifying associations of cord blood methylation profiles with measures of newborn adiposity. Neonatal adiposity is a risk factor for childhood obesity. Investigating contributors to neonata adiposity is important for understanding early life obesity risk. Epigenetic changes of metabolic genes in cord blood may contribute to excessive neonatal adiposity and subsequent childhood obesity. This study aims to evaluate the association of cord blood DNA methylation patterns with markers of neonatal adiposity
Project description:Transposable elements (TEs) are robustly silenced by multiple epigenetic marks, but dynamics of crosstalk among these marks remains enigmatic. In Arabidopsis, TEs are silenced by cytosine methylation in both CpG and non-CpG contexts (mCG and mCH) and histone H3 lysine 9 methylation (H3K9me). While mCH and H3K9me are mutually dependent for their maintenance, mCG and mCH/H3K9me are independently maintained. Here we show that establishment, rather than maintenance, of mCH depends on mCG, accounting for the synergistic colocalization of these silent marks in TEs. When mCG is lost, establishment of mCH is abolished in TEs. mCG also guides mCH in active genes, although the resulting mCH/H3K9me is removed thereafter. Unexpectedly, targeting efficiency of mCH depends on relative, rather than absolute, levels of mCG within the genome, suggesting underlying global negative controls. We propose that local positive feedback in heterochromatin dynamics, together with global negative feedback, drive robust and balanced DNA methylome patterning.