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Garcia-Nieto, P. E.

Publications and source records attributed to Garcia-Nieto, P. E..

3 recordsLinked to original sources

Transcriptome diversity is a systematic source of bias in RNA-sequencing data

BackgroundRNA sequencing has been widely used as an essential tool to probe gene expression. While standard practices have been established to analyze RNA-seq data, it is still challenging to detect and remove artifactual signals. Several factors such as sex, age, and sequencing technology have been found to bias these estimates. Probabilistic estimation of expression residuals (PEER) has been used to account for some systematic effects, but it has remained challenging to interpret these PEER factors. ResultsHere we show that transcriptome diversity - a simple metric based on Shannon entropy - explains a large portion of variability in gene expression, and is a major factor detected by PEER. We then show that transcriptome diversity has significant associations with multiple technical and biological variables across diverse organisms and datasets. This prevalent confounding factor provides a simple explanation for a major source of systematic biases in gene expression estimates. ConclusionsOur results show that transcriptome diversity is a metric that captures a systematic bias in RNA-seq and is the strongest known factor encoded in PEER covariates.

genomics↗

The somatic mutation landscape of the human body

Somatic mutations in healthy tissues contribute to aging, neurodegeneration, and cancer initiation, yet remain largely uncharacterized. To gain a better understanding of their distribution and functional impacts, we leveraged the genomic information contained in the transcriptome to uniformly call somatic mutations from over 7,500 tissue samples, representing 36 distinct tissues. This catalog, containing over 280,000 mutations, revealed a wide diversity of tissuespecific mutation profiles associated with gene expression levels and chromatin states. We found pervasive negative selection acting on missense and nonsense mutations, except for mutations previously observed in cancer samples, which were under positive selection and were highly enriched in many healthy tissues. These findings reveal fundamental patterns of tissue-specific somatic evolution and shed light on aging and the earliest stages of tumorigenesis.

genomics↗

The INO80 Chromatin Remodeler Sustains Metabolic Stability by Promoting TOR Signaling and Regulating Histone Acetylation

Chromatin remodeling complexes are essential for gene expression programs that coordinate cell function with metabolic status. However, how these remodelers are integrated in metabolic stability pathways is not well known. Here, we report an expansive genetic screen with chromatin remodelers and metabolic regulators in Saccharomyces cerevisiae. We found that, unlike the SWR1 remodeler, the INO80 chromatin remodeling complex is composed of multiple distinct functional subunit modules. We identified a strikingly divergent genetic signature for the Ies6 subunit module that links the INO80 complex to metabolic homeostasis, including mitochondrial maintenance. INO80 is also needed to communicate TORC1-mediated signaling to chromatin and maintains histone acetylation at TORC1-responsive genes. Furthermore, computational analysis reveals subunits of INO80 and mTORC1 have high co-occurrence of alterations in human cancers. Collectively, these results demonstrate that the INO80 complex is a central component of metabolic homeostasis that influences histone acetylation and may contribute to disease when disrupted.

genetics↗