研究成果

Oct, 2024
Cellular bioenergetics and mitochondrial dynamics are crucial for the secretion of insulin by pancreatic beta cells in response to elevated levels of blood glucose. To elucidate the interactions between energy production and mitochondrial fission/fusion dynamics, we combine live-cell mitochondria imaging with biophysical-based modeling and graph-based network analysis. The aim is to determine the mechanism that regulates mitochondrial morphology and balances metabolic demands in pancreatic beta cells. A minimalistic differential equation-based model for beta cells is constructed that includes glycolysis, oxidative phosphorylation, calcium dynamics, and fission/fusion dynamics, with ATP synthase flux and proton leak flux as main regulators of mitochondrial dynamics. The model shows that...

Oct, 2024
Leaves of the carnivorous sundew plants (Drosera spp.) secrete mucilage that hosts microorganisms, but whether this microbiota contributes to prey digestion is unclear. We identified the acidophilic fungus Acrodontium crateriforme as the dominant species in the mucilage microbial communities, thriving in multiple sundew species across the global range. The fungus grows and sporulates on sundew glands as its preferred acidic environment, and its presence in traps increased the prey digestion process. A. crateriforme has a reduced genome similar to other symbiotic fungi. During A. crateriforme-Drosera spatulata coexistence and digestion of prey insects, transcriptomes revealed significant gene co-option in both partners. Holobiont expression patterns during prey digestion further revealed...

Sep, 2024
Over the past decade, genome-wide association studies have identified thousands of variants significantly associated with complex traits. For each locus, gene expression levels are needed to further explore its biological functions. To address this, the PrediXcan algorithm leverages large-scale reference data to impute the gene expression level from single nucleotide polymorphisms, and thus the gene-trait associations can be tested to identify the candidate causal genes. However, a challenge arises due to the fact that most reference data are from subjects of European ancestry, and the accuracy and robustness of predicted gene expression in subjects of East Asian (EAS) ancestry remains unclear. Here, we first simulated a variety of scenarios to explore the impact of the level of...

Sep, 2024
The killer-cell immunoglobulin-like receptor (KIR) gene complex, a highly polymorphic region of the human genome that encodes proteins involved in immune responses, poses strong challenges in genotyping owing to its remarkable genetic diversity and structural intricacy. Accurate analysis of KIR alleles, including their structural variations, is crucial for understanding their roles in various immune responses. Leveraging the high-quality genome assemblies from the Human Pangenome Reference Consortium (HPRC), we present a novel bioinformatic tool, the structural KIR annoTator (SKIRT), to investigate gene diversity and facilitate precise KIR allele analysis. In 47 HPRC-phased assemblies, SKIRT identifies a recurrent novel KIR2DS4/3DL1 fusion gene in the paternal haplotype of HG02630 and...

Sep, 2024
Ovarian clear cell carcinoma (OCCC) is a histological subtype of epithelial ovarian cancer with distinct pathological features, molecular profiles, and biological functions. OCCC has high incidence rates in East Asia compared to the Western hemisphere and Europe and is associated with endometriosis. With its relative resistance to conventional treatment regimens and the worst stage-adjusted prognosis among ovarian cancer subtypes, there is an urgent need to optimize therapeutic options and to improve patient outcomes. To achieve this goal, better patient stratification strategies are required. These strategies could derive from comprehensive and in-depth multidimensional analysis of tumor heterogeneity. Understanding intertumor heterogeneity could assist us in stratifying OCCC patients...

Sep, 2024
The ability to catalyze reversible DNA cleavage and religation is central to topoisomerases' role in regulating DNA topology. In type IIA topoisomerases (Top2), the formation of its DNA cleavage-religation center is driven by DNA-binding-induced structural rearrangements. These changes optimally position key catalytic modules, such as the active site tyrosine of the WHD domain and metal ion(s) chelated by the TOPRIM domain, around the scissile phosphodiester bond to perform reversible transesterification. To understand this assembly process in detail, we report the catalytic core structures of human Top2α and Top2β in an on-pathway conformational state. This state features an in trans formation of an interface between the Tower and opposing TOPRIM domain, revealing a groove for...

Sep, 2024
Introduction: Sensorineural hearing impairment (SNHI), a common childhood disorder with heterogeneous genetic causes, can lead to delayed language development and psychosocial problems. Next-generation sequencing (NGS) offers high-throughput screening and high-sensitivity detection of genetic etiologies of SNHI, enabling clinicians to make informed medical decisions, provide tailored treatments, and improve prognostic outcomes. Areas covered: This review covers the diverse etiologies of HHI and the utility of different NGS modalities (targeted sequencing and whole exome/genome sequencing), and includes HHI-related studies on newborn screening, genetic counseling, prognostic prediction, and personalized treatment. Challenges such as the trade-off between cost and diagnostic yield,...

Aug, 2024
Vitiligo is a common acquired disease of pigment loss. In lesions recalcitrant to non-invasive treatment, transplantation of cultured autologous melanocytes is an emerging choice. Conventionally, the recipient site is often prepared by laser-mediated or mechanical dermabrasion. Such preparation procedures have disadvantages including prolonged transplantation duration, long period for reepithelialization and potential scarring. We propose a method of preparing recipient sites by psoralen and controlled ultraviolet A (PUVA)-induced blistering followed by transplanting suspended melanocytes. We introduced this method in 10 patients with segmental vitiligo on their recipient site 3 to 5 days before transplantation and blistering developed in 2 to 3 days afterwards. On the day of...

Aug, 2024
Predicting drug responses based on individual transcriptomic profiles holds promise for refining prognosis and advancing precision medicine. Although many studies have endeavored to predict the responses of known drugs to novel transcriptomic profiles, research into predicting responses for newly discovered drugs remains sparse. In this study, we introduce scDrug+, a comprehensive pipeline that seamlessly integrates single-cell analysis with drug-response prediction. Importantly, scDrug+ is equipped to predict the response of new drugs by analyzing their molecular structures. The open-source tool is available as a Docker container, ensuring ease of deployment and reproducibility. It can be accessed at https://github.com/ailabstw/scDrugplus.

Jul, 2024
RNA helicase DHX9 is essential for genome stability by resolving aberrant R-loops. However, its regulatory mechanisms remain unclear. Here we show that SUMOylation at lysine 120 (K120) is crucial for DHX9 function. Preventing SUMOylation at K120 leads to R-loop dysregulation, increased DNA damage, and cell death. Cells expressing DHX9 K120R mutant which cannot be SUMOylated are more sensitive to genotoxic agents and this sensitivity is mitigated by RNase H overexpression. Unlike the mutant, wild-type DHX9 interacts with R-loop-associated proteins such as PARP1 and DDX21 via SUMO-interacting motifs. Fusion of SUMO2 to the DHX9 K120R mutant enhances its association with these proteins, reduces R-loop accumulation, and alleviates survival defects of DHX9 K120R. Our findings highlight the...