Project description:We used RNA sequencing to analyze transcript profiles of ten autopsy brain regions from ten subjects. RNA sequencing techniques were designed to detect both coding and non-coding RNA, splice isoform composition, and allelic expression. Brain regions were selected from five subjects with a documented history of smoking and five non-smokers. Paired-end RNA sequencing was performed on SOLiD instruments to a depth of >40 million reads, using linearly amplified, ribosomally depleted RNA. 12 thousand protein coding and 2 thousand lncRNA transcripts were detectable at a conservative threshold. Of the aligned reads, 52% were exonic, 34% intronic and 14% intergenic. A majority of protein coding genes (65%) was expressed in all regions, whereas ncRNAs displayed a more restricted distribution. Profiles of RNA isoforms varied across brain regions and subjects at multiple gene loci, with neurexin 3 (NRXN3) a prominent example. Allelic RNA ratios deviating from unity were identified in > 400 genes, detectable in both protein-coding and non-coding genes, indicating the presence of cis-acting regulatory variants. RNA sequencing identifies distinct and consistent differences in gene expression between brain regions, with non-coding RNA displaying greater diversity between brain regions than mRNAs. Numerous RNAs exhibit robust allele selective expression, proving a means for discovery of cis-acting regulatory factors with potential clinical relevance. Sequenced whole transcriptomes of 10 brain regions from 10 individuals, 5 smokers and 5 nonsmokers
Project description:We used RNA sequencing to analyze transcript profiles of ten autopsy brain regions from ten subjects. RNA sequencing techniques were designed to detect both coding and non-coding RNA, splice isoform composition, and allelic expression. Brain regions were selected from five subjects with a documented history of smoking and five non-smokers. Paired-end RNA sequencing was performed on SOLiD instruments to a depth of >40 million reads, using linearly amplified, ribosomally depleted RNA. 12 thousand protein coding and 2 thousand lncRNA transcripts were detectable at a conservative threshold. Of the aligned reads, 52% were exonic, 34% intronic and 14% intergenic. A majority of protein coding genes (65%) was expressed in all regions, whereas ncRNAs displayed a more restricted distribution. Profiles of RNA isoforms varied across brain regions and subjects at multiple gene loci, with neurexin 3 (NRXN3) a prominent example. Allelic RNA ratios deviating from unity were identified in > 400 genes, detectable in both protein-coding and non-coding genes, indicating the presence of cis-acting regulatory variants. RNA sequencing identifies distinct and consistent differences in gene expression between brain regions, with non-coding RNA displaying greater diversity between brain regions than mRNAs. Numerous RNAs exhibit robust allele selective expression, proving a means for discovery of cis-acting regulatory factors with potential clinical relevance.
Project description:<p><b>BRAINCODE: How Does the Human Genome Function in Specific Brain Neurons?</b> The human brain comprises about 86 billion neurons whose function is central to human biology. How does the human genome program high performing neurons and neural networks in response to experience? What subprograms does the genome express in physiologically and morphologically distinct brain cells? The goal of the BRAIN Cell encyclOpeDia of transcribed Elements Consortium (BRAINcode) is to provide a map of gene expression - both protein-coding and non-coding - in specific cell types, not in culture, but in situ in brains of people. Going beyond traditional mRNA sequencing, polyadenylated and non-polyadenylated transcripts were ultra deeply sequenced using ribo-depleted RNA from neurons laser-captured from human post-mortem brains. Three prototypical neuron types, dopamine neurons, pyramidal neurons, and Betz cells, were prioritized because of their key biologic roles and differential vulnerability to important neurodegenerative diseases such as Parkinson's or Alzheimer's disease. Genetic variation between individuals was examined for correlation with differences in transcribed sequences to identify regions of the genome that influence whether, how, and how much a transcript is expressed in specific cell types in human brains. Our results indicate a vast universe of annotated and novel non-coding RNAs expressed in brain cells and suggest a more diverse and much more complex transcriptional architecture than previously imagined. </p>
Project description:Interventions: Case series:Nil
Primary outcome(s): intestinal microecological disorders;blood non-coding RNAs and immune status
Study Design: Randomized parallel controlled trial
Project description:Genomic analyses in budding yeast have helped to define the foundational principles of eukaryotic gene expression, but have systematically excluded specific classes of potential coding regions, including those with non-AUG start codons. Without methods to define coding regions empirically, the prevalence of these non-canonical coding regions has been impossible to assess. Here, we applied an experimental approach to globally annotate translation initiation sites in yeast and identified a class of 149 genes that encode N-terminally extended alternate protein isoforms that result from translation initiation at non-AUG codons upstream of the annotated AUG start codon. These alternate isoforms are produced in concert with canonical isoforms and are translated with a high degree of specificity, resulting from initiation at only a small subset of possible start codons in 5’ leader regions. Their translation is enriched during meiosis, and is induced by low eIF5A levels, which are observed in this context. These findings reveal widespread production of non-canonical protein isoforms and, more generally, show unexpected complexity to the rules by which the budding yeast genome is decoded.
Project description:We report the application of high-throughput RNA sequencing to the human prefrontal cortex. The brain dataset was obtained by sequencing total RNAs extracted from the dorsolateral prefrontal cortex of five deceased human patients with no apparent pathology, followed by depletion of ribosomal RNA to obtain all non-rRNA coding and non-coding RNAs in the human brain transcriptome.