Biology subjects

Payer, L. M.

Publications and source records attributed to Payer, L. M..

3 recordsLinked to original sources

bioRxiv2020

Polymorphic mobile element insertions contribute to gene expression and alternative splicing in human tissues

BackgroundMobile elements are a major source of human structural variants and some mobile elements can regulate gene expression and alternative splicing. However, the impact of polymorphic mobile element insertions (pMEIs) on gene expression and splicing in diverse human tissues has not been thoroughly studied. The multi-tissue gene expression and whole genome sequencing data generated by the Genotype-Tissue Expression (GTEx) project provide a great opportunity to systematic determine pMEIs role in gene expression regulation in human tissues. ResultsUsing the GTEx whole genome sequencing data, we identified 20,545 high-quality pMEIs from 639 individuals. We then identified pMEI-associated expression quantitative trait loci (eQTLs) and splicing quantitative trait loci (sQTLs) in 48 tissues by joint analysis of variants including pMEIs, single-nucleotide polymorphisms, and insertions/deletions. pMEIs were predicted to be the potential causal variant for 3,522 of the 30,147 significant eQTLs, and 3,717 of the 21,529 significant sQTLs. The pMEIs associated eQTLs and sQTLs show high level of tissue-specificity, and the pMEIs were enriched in the proximity of affected genes and in regulatory elements. Using reporter assays, we confirmed that several pMEIs associated with eQTLs and sQTLs can alter gene expression levels and isoform proportions. ConclusionOverall, our study shows that pMEIs are associated with thousands of gene expression and splicing variations in different tissues, and pMEIs could have a significant role in regulating tissue-specific gene expression/splicing. Detailed mechanisms for pMEIs role in gene regulation in different tissues will be an important direction for future human genomic studies.

genomics↗

bioRxiv2019

TypeTE: a tool to genotype mobile element insertions from whole genome resequencing data

Alu retrotransposons account for more than 10% of the human genome, and insertions of these elements create structural variants segregating in human populations. Such polymorphic Alu are powerful markers to understand population structure, and they represent variants that can greatly impact genome function, including gene expression. Accurate genotyping of Alu and other mobile elements has been challenging. Indeed, we found that Alu genotypes previously called for the 1000 Genomes Project are sometimes erroneous, which poses significant problems for phasing these insertions with other variants that comprise the haplotype. To ameliorate this issue, we introduce a new pipeline -- TypeTE -- which genotypes Alu insertions from whole-genome sequencing data. Starting from a list of polymorphic Alus, TypeTE identifies the hallmarks (poly-A tail and target site duplication) and orientation of Alu insertions using local re-assembly to reconstruct presence and absence alleles. Genotype likelihoods are then computed after re-mapping sequencing reads to the reconstructed alleles. Using a gold standard set of PCR-based genotyping of >200 loci, we show that TypeTE improves genotype accuracy from 83% to 92% in the 1000 Genomes dataset. TypeTE can be readily adapted to other retrotransposon families and brings a valuable toolbox addition for population genomics.

bioinformatics↗

bioRxiv2018

SQuIRE: Software for Quantifying Interspersed Repeat Elements

Transposable elements are interspersed repeat sequences that make up much of the human genome. Conventional approaches to RNA-seq analysis often exclude these sequences, fail to optimally adjudicate read alignments, or align reads to interspersed repeat consensus sequences without considering these transcripts in their genomic contexts. As a result, repetitive sequence contributions to transcriptomes are not well understood. Here, we present Software for Quantifying Interspersed Repeat Expression (SQuIRE), an RNA-seq analysis pipeline that integrates repeat and genome annotation (RepeatMasker), read alignment (STAR), gene expression (StringTie) and differential expression (DESeq2). SQuIRE uniquely provides a locus-specific picture of interspersed repeat-encoded RNA expression. SQuIRE can be downloaded at (github.com/wyang17/SQuIRE).

bioinformatics↗