Project description:We compared the genome-wide patterns of DNA methylation in the brains of humans to those of our closest evolutionary relative, chimpanzees, using base-pair resolution whole-genome methylation maps of the prefrontal cortex. Our data reveal that the prefrontal cortex is the most heavily methylated among the human tissues examined so far. Nevertheless, hundreds of genes exhibit dramatically reduced levels of promoter DNA methylation in the human brain relative to the chimpanzee brain. Many of these genes are associated with neurological disorders, psychological disorders, and cancers, and are enriched for functions related to cellular metabolic processes and protein binding. Moreover, the majority of these genes exhibit higher expression in the human brain compared to the chimpanzee brain. Profiling DNA methylation map in prefrontal cortex regions of postmortem brains of three humans and three chimpanzees
Project description:We compared the genome-wide patterns of DNA methylation in the brains of humans to those of our closest evolutionary relative, chimpanzees, using base-pair resolution whole-genome methylation maps of the prefrontal cortex. Our data reveal that the prefrontal cortex is the most heavily methylated among the human tissues examined so far. Nevertheless, hundreds of genes exhibit dramatically reduced levels of promoter DNA methylation in the human brain relative to the chimpanzee brain. Many of these genes are associated with neurological disorders, psychological disorders, and cancers, and are enriched for functions related to cellular metabolic processes and protein binding. Moreover, the majority of these genes exhibit higher expression in the human brain compared to the chimpanzee brain.
Project description:we used RNA-Seq to quantify the RNA editing level at more than 8,000 previously annotated exonic A-to-I RNA editing sites in two brain regions - prefrontal cortex and cerebellum - of humans, chimpanzees and rhesus macaques. We observed substantial conservation of RNA editing levels between the brain regions, as well as among the three primate species. Evolutionary changes in RNA editing were nonetheless evident among the species. Across lifespan, we observed an increase of the RNA editing level with advanced age in both brain regions of all three primate species. poly(A) enriched RNAs extracted from pooled samples of two brain regions: CBC and PFC of chimpanzee and macaque, fragmented, revers transcribed to double-stranded cDNA using random hexamers. Sequencing libraries were prepared according to the paired-end non-strand-specific sample preparation protocol of Illumina. Each sample was sequenced in a separate lane in the Illumina Genome Analyzer II system, using the 75-bp paired-end sequencing protocol. human data was downloaded from SRA [SRP005169]
Project description:Single-nucleus RNA sequencing (snRNA-seq) was used to profile the transcriptome of 12,352 nuclei in chimpanzee adult testis. This dataset includes three samples from three different individuals. This dataset is part of a larger evolutionary study of adult testis at the single-nucleus level (97,521 single-nuclei in total) across mammals including 10 representatives of the three main mammalian lineages: human, chimpanzee, bonobo, gorilla, gibbon, rhesus macaque, marmoset, mouse (placental mammals); grey short-tailed opossum (marsupials); and platypus (egg-laying monotremes). Corresponding data were generated for a bird (red junglefowl, the progenitor of domestic chicken), to be used as an evolutionary outgroup.
Project description:Accelerated brain development is a unique feature of the human species. Not only the size but also morphology, in particular the connections between frontal cortex and basal ganglia distinguish the human brain from great apes and other primates. Recent findings suggest that structural features which may be important for language acquisition are influenced by FOXP2, key regulator of CNTNAP2. CNTNAP2 is one of the largest genes in the chimpanzee genome, encompassing 2.5 Mb. It encodes a neurexin with essential roles in the vertebrate nervous system. The aim of our study was to compare the methylation patterns of CNTNAP2 in human and chimpanzee brains, assuming that epigenetic regulation is essential for brain development and human language abilities. To this end, we designed a NimbleGen tiling array covering the entire chimpanzee CNTNAP2 gene plus 0.1 Mb up- and downstream flanking sequence with an average resolution of 13 bp. Methylated DNA ImmunoPreciptation (MeDIP) was used to enrich cytosine-methylated DNA fragments for downstream analysis with high-resolution tiling arrays.
Project description:The aim of this study was to characterize the genome-wide DNA methylation profiles of chimpanzee trabecular bone samples (n=4), identify how they relate to aspects of femur bone morphology, and assess how these epigenetic patterns relate to those in other primate taxa. The Illumina Infinium MethylationEPIC array was used to assess genome-wide methylation patterns.
Project description:Human accelerated regions (HARs) are evolutionarily conserved sequences that acquired human-specific nucleotide changes and reside in genomic regions associated with unique human traits and disease. The majority of HARs (96%) are noncoding, a few of which have been shown to be functional enhancers. Here, we comprehensively tested human and chimpanzee sequences of HARs (N=714) for enhancer activity using a lentivirus-based massively parallel reporter assay (lentiMPRA) in human and chimpanzee iPSC derived neural progenitors at two differentiation time points. We found that 43% (306/714) function as enhancers and over two-thirds (204/306) showed consistent differences in activity between human and chimpanzee sequences across conditions. We also tested all possible permutations of substitutions in seven HARs and found significant positive and negative interactions. Our study provides a comprehensive resource of functional neurodevelopmental HAR enhancers and shows that multiple interacting sites drive evolutionary activity differences.
Project description:we used RNA-Seq to quantify the RNA editing level at more than 8,000 previously annotated exonic A-to-I RNA editing sites in two brain regions - prefrontal cortex and cerebellum - of humans, chimpanzees and rhesus macaques. We observed substantial conservation of RNA editing levels between the brain regions, as well as among the three primate species. Evolutionary changes in RNA editing were nonetheless evident among the species. Across lifespan, we observed an increase of the RNA editing level with advanced age in both brain regions of all three primate species.
Project description:Accelerated brain development is a unique feature of the human species. Not only the size but also morphology, in particular the connections between frontal cortex and basal ganglia distinguish the human brain from great apes and other primates. Recent findings suggest that structural features which may be important for language acquisition are influenced by FOXP2, key regulator of CNTNAP2. CNTNAP2 is one of the largest genes in the chimpanzee genome, encompassing 2.5 Mb. It encodes a neurexin with essential roles in the vertebrate nervous system. The aim of our study was to compare the methylation patterns of CNTNAP2 in human and chimpanzee brains, assuming that epigenetic regulation is essential for brain development and human language abilities. To this end, we designed a NimbleGen tiling array covering the entire chimpanzee CNTNAP2 gene plus 0.1 Mb up- and downstream flanking sequence with an average resolution of 13 bp. Methylated DNA ImmunoPreciptation (MeDIP) was used to enrich cytosine-methylated DNA fragments for downstream analysis with high-resolution tiling arrays. MeDIP-based CNTNAP2 methylation profiling