Biology subjects

Yang, Y.-J.

Publications and source records attributed to Yang, Y.-J..

3 recordsLinked to original sources

bioRxiv2026

Somatic haplotype reconstruction and variant recalibration from tumor-only long-read sequencing

Separating somatic from germline variants and reconstructing somatic haplotypes are the two central problems of tumor-only cancer genome analysis. Long reads carry the linkage needed to solve both, but chromosome-scale loss of heterozygosity (LOH) and an unknown degree of normal-cell admixture blur the distinction between somatic and germline haplotypes. Here we present LongPhase-TO, the first method to reconstruct somatic haplotypes from a tumor sample alone. Rather than mapping somatic variants onto germline haplotypes, LongPhase-TO co-phases germline and somatic alleles in a unified graph, in which LOH and tumor DNA fraction are resolved internally from heterozygosity depletion and haplotype imbalance rather than a copy-number and ploidy model. Across eight datasets from six cancer cell lines, LongPhase-TO increased haplotype block N50 by a median of 2.9-fold relative to germline phasers. It also consistently improved somatic single-nucleotide variant (SNV) and indel calls from ClairS-TO and DeepSomatic-TO, raising mean F1 from 0.55 to 0.62 and 0.65 for SNVs and from 0.19 to 0.23 for indels, with the largest gains at low tumor DNA fraction. Across breast, melanoma and lung cancer cell lines, LongPhase-TO improves the accuracy of existing somatic callers and reconstructs megabase-scale somatic haplotypes.

bioinformatics↗

bioRxiv2026

Autoimmune diabetes-dependent c-Maf SUMOylation licenses inflammatory bowel disease by reshaping the gut microbiota

We have previously demonstrated a critical role of c-Maf SUMOylation in the regulation of autoimmune diabetogenesis, but its physiological relevance to and potential clinical impact on gut inflammation need further elucidation. Here, integrating a 14-year population-based time-trend cohort study of 139,204 type 1 diabetes patients with experiments in non-obese diabetic mice, we illustrated that autoimmune diabetes confers resistance to colitis mediated by an impaired c-Maf SUMOylation-driven IL-21-IgA axis. Utilizing T cell-specific c-Maf SUMOylation site-mutated mice, we further demonstrated that SUMOylation-defective c-Maf enhances IL-21 expression in CD4+ T cells to promote fecal IgA production and colitis resistance via microbiota remodeling, specifically through Lactobacillus johnsonii enrichment and activating lithocholic acid (LCA)-mediated AMPK anti-inflammatory pathway. Pharmacological HDAC2 inhibition by BRD6688 promotes c-Maf-mediated IL-21 and suppresses colitis in PBMC-humanized mice. Altogether, we revealed how SUMOylation reciprocally modulates the inflammatory process between autoimmune diabetes and colitis in a T cell-restricted and single transcription factor-based manner.

immunology↗

bioRxiv2021

Observation of reversal in twist-stretch coupling of RNA suggests a unified mechanism for the opposite couplings of DNA and RNA

The functions of DNA and RNA rely on their deformations. When stretched, both DNA and RNA duplexes change their twist angles through twist-stretch coupling. The coupling is negative for DNA but positive for RNA, which is not yet completely understood. Here, our magnetic tweezers experiments show that the coupling of RNA reverses from positive to negative by multivalent cations. Combining with the previously reported tension-induced negative-to-positive coupling-reversal of DNA, we propose a unified mechanism of the couplings of both RNA and DNA based on molecular dynamics simulations. Two deformation pathways are competing when stretched: shrinking the radius causes positive couplings but widening the major groove causes negative couplings. For RNA whose major groove is clamped by multivalent cations and canonical DNA, their radii shrink when stretched, thus exhibiting positive couplings. For elongated DNA whose radius already shrinks to the minimum and canonical RNA, their major grooves are widened when stretched, thus exhibiting negative coupling.

biophysics↗