H-SPA
Ontology highlight
ABSTRACT:
PROVIDER: PRJEB20181 | ENA |
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| ERR1904960.fastq.gz | Fastqsanger.gz | |||
| ERR1904970.fastq.gz | Fastqsanger.gz | |||
| ERR1904980.fastq.gz | Fastqsanger.gz | |||
| ERR1904990.fastq.gz | Fastqsanger.gz | |||
| ERR1905000.fastq.gz | Fastqsanger.gz |
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Project description:Coupling molecular biology to high throughput sequencing has revolutionized the study of biology. Molecular genomics techniques are continually refined to provide higher resolution mapping of nucleic acid interactions and nucleic acid structure. These assays are converging on single-nucleotide resolution measurements, but the sequence preferences of molecular biology enzymes can interfere with the accurate interpretation of the data. Enzymatic sequence preferences manifest more prominently as the resolution of these assays increase. We developed seqOutBias to seek out enzymatic sequence bias from experimental data and scale individual sequence reads to correct the bias. We show that this software efficiently and successfully corrects the sequence bias resulting from DNase-seq, TACh-seq, ATAC-seq, MNase-seq, and PRO-seq data.
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Project description:The Dicer ribonuclease III (RNase III) enzymes process long double-stranded RNA (dsRNA) into the small interfering RNAs (siRNAs) that direct RNA interference. Here, we describe the structure and activity of a catalytically active fragment of Kluyveromyces polysporus Dcr1, which represents the noncanonical Dicers found in budding yeast. The crystal structure reveals a homodimer that resembles bacterial RNase III but includes a novel N-terminal domain and newly identified catalytic residues conserved throughout eukaryotic RNase III enzymes. Biochemical analyses show that Dcr1 dimers bind cooperatively along the dsRNA substrate and cleave at precise intervals based on the distance between consecutive active sites. Thus, unlike canonical Dicers, which successively remove siRNA duplexes from the dsRNA termini, Dcr1 initiates processing in the interior and works outward. The distinct mechanism of budding-yeast Dicers establishes a novel paradigm for natural protein-based molecular rulers and imparts substrate preferences with ramifications for biological function.
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