Biology subjects

Gan, G.

Publications and source records attributed to Gan, G..

6 recordsLinked to original sources

bioRxiv2026

Multimodal longitudinal prediction of alcohol-use trajectories in adolescents and young adults: Social context, real-life social affective benefit, and fronto-striatal involvement

Escalating alcohol use during adolescence and young adulthood confers substantial risk for later substance misuse and adverse mental health outcomes, yet the factors that determine early drinking trajectories remain poorly understood. Here, we examined alcohol use across social, affective, and neural domains in a cohort of 378 community-based young drinkers using a combination of longitudinal phenotyping, ecological momentary assessment (EMA) and functional neuroimaging. Across different levels of analysis, higher baseline alcohol consumption (standard drinks per week) was associated with immediate substance-use social context, greater social-affective benefit in daily life, and heightened engagement of the fronto-striatal reward circuitry. In a one-year longitudinal follow-up, individual social-affective benefit and substance-related social environmental factors showed the strongest predictive value for drinking trajectories in a follow-up of 219 individuals after one year. Our findings identify key social and neural reward-related determinants of youth drinking behavior, informing the development of evidence-based risk detection and prevention measures.

neuroscience↗

bioRxiv2025

Streptococcus mutans LiaS gene regulates its cross-kingdom interactions with Candida albicans to promote oral candidiasis

Candida albicans and Streptococcus mutans are commonly associated with oral candidiasis and dental caries, respectively. C. albicans is frequently detected in the dental plaque of early childhood caries. The synergistic interaction between C. albicans and S. mutans in dental caries suggests that fungi enhance the production of acidic metabolites and contributes to the development of caries. However, the cross-kingdom interaction of S. mutans in oral candidiasis and the pathways regulating hyphal formation remain unclear. The liaS gene of S. mutans 593 plays a crucial role in maintaining membrane homeostasis. In comparison to the S. mutans 593 and liaS- complementary strains, the liaS- strain significantly diminished the proliferation, biofilm formation, extracellular polysaccharide production, and C. albicans hyphal transformation of co-cultured microorganisms. The deletion of liaS gene in the dual-species downregulated the expression of yeast-hyphal transformation related genes hwp1, ece1, als1, and als3 in C. albicans, while also impacted the expression of phr1 and phr2. Additionally, liaS- inhibited glycolysis and pyruvate kinase activity in S. mutans, leading to a decreased in water-soluble and water-insoluble glucans production in biofilm. The significant downregulation of glucosyltransferase transcription relates genes expression in liaS- resulted in inhibition of the cross-kingdom interaction in the dual-species. In the murine oropharyngeal candidiasis model, dual-species infection with liaS- results in a reduction of fungal and hyphal invasion compared to the combinations of C. albicans and S. mutans 593. In conclusion, S. mutans/liaS play a crucial role in the development of oral candidiasis suggests that it could be a targeted strategy for managing this condition. ImportanceCandidiasis involves the transition of C. albicans into hyphae and the fungi invasion of the oropharyngeal mucosa. The transformation of hyphal is influenced by a variety of internal and external environmental factors. Our research findings suggest that the deletion of the liaS gene leads to a reduction in gtfs gene expression, impacting glycolysis efficiency and effectively decreasing EPS production in the dual-species biofilm. Also, downregulation of the expression levels of yeast-hyphal transformation related genes to inhibiting the virulence function of C. albicans. Our study demonstrates that S. mutans 593/liaS promotes epithelial invasion of C. albicans in mouse oropharyngeal candidiasis, offering a potential therapeutic approach for addressing cross-kingdom infections.

microbiology↗

bioRxiv2024

Engineering a ribozyme with aminoacyl-tRNA synthetase activity

A ribozyme that can charge a tRNA with amino acids and discriminate between cognate and non-cognate tRNAs is of interest because an RNA with this ability may have been a critical for translation in the transition from the RNA world. In addition, it could provide a tool for incorporating non-canonical amino acids for biotechnology applications. Here, we rationally engineer a ribozyme by fusing a tRNA binding module derived from a T-box riboswitch with a catalytic module (a flexizyme) to generate a ribozyme that can amino acylate a target tRNA. We demonstrate that this ribozyme be readily redesigned to alter tRNA specificity. This ribozyme is compatible with an in vitro translation system and could be used to recode a protein sequence to site-specifically incorporate a non-canonical amino acid.

biochemistry↗

bioRxiv2024

Transplantation of exogenous mitochondria mitigates myocardial dysfunction after cardiac arrest

The incidence of post-cardiac arrest myocardial dysfunction (PAMD) is high, and there is currently no effective treatment available. This study aims to investigate the protective effects of exogenous mitochondrial transplantation. Exogenous mitochondrial transplantation can enhance myocardial function and improve the survival rate. Mechanistic studies suggest that mitochondrial transplantation can limit impairment in mitochondrial morphology, augment the activity of mitochondrial complexes II and IV, and raise ATP level. As well, mitochondrial therapy ameliorated oxidative stress imbalance, reduced myocardial injury, and thus improved PAMD after cardiopulmonary resuscitation (CPR).

systems biology↗

bioRxiv2019

Genome sequence and analysis of the eggplant (Solanum melongena L.)

The eggplant (Solanum melongena L.) is one of the most important Solanaceae crops, ranking third in the total production and economic value in the genus Solanum. Here, we report a high-quality, chromosome-scale eggplant reference genome sequence of 1,155.8 Mb, with N50 of 93.9 Mb, which was assembled by combining PacBio long reads and Hi-C sequencing data. Repetitive sequences occupied 70.1% of the assembly length, and 35,018 high-confidence protein-coding genes were annotated based on multiple evidence. Comparative analysis revealed 646 species-specific families and 364 positive selection genes, conferring distinguishing traits to the eggplant. We performed genome-wide identification of disease resistance genes and discovered an expanded gene family of bacterial spot resistance in the eggplant and pepper but not in tomato and potato. The genes involved in chlorogenic acid synthesis were comprehensively characterized. Highly similar chromosomal distribution patterns of polyphenol oxidase genes were observed in the eggplant, tomato, and potato genomes. The eggplant reference genome sequence will not only facilitate evolutionary studies in the Solanaceae but also facilitate their breeding and improvement.

genomics↗

bioRxiv2019

Alpha-ketoglutarate, an endogenous metabolite, extends lifespan and compresses morbidity in aging mice

The decline in early life mortality since the 1950s has resulted in dramatic demographic shift towards aged population. Aging manifests as a decline in health, multiple organ dysfunction and increased vulnerability to diseases, which degrades quality of life. A verity of genetic and pharmacological interventions, mostly from non-vertebrate models, have been identified that can enhance lifespan. Whether these interventions extend healthspan, the disease free and functional period of life, has only sometimes been tested and is often a matter of debate. Human aging indices have been developed to assess elements of functional decline with aging (e.g. sarcopenia, cognitive function). However, corresponding comprehensive indices in mice are seldom applied to aging studies. To probe the relationship between healthspan and lifespan extension in mammals, we performed a series of longitudinal, clinically-relevant healthspan measurements. Metabolism and aging are tightly connected and specific perturbations of nutrient-sensing pathways can enhance longevity in laboratory animals. Here we show that alpha-ketoglutarate (delivered in the form of a Calcium salt, CaAKG), a key metabolite in tricarboxylic (TCA) cycle that is reported to extend lifespan in worms, can significantly extend lifespan and healthspan in mice. AKG is involved in various fundamental processes including collagen synthesis and epigenetic changes. Due to its broad roles in multiple biological processes, AKG has been a subject of interest for researchers in various fields. AKG also influences several age-related processes, including stem cell proliferation and osteoporosis. To determine its role in mammalian aging, we administered CaAKG in 18 months old mice and determined its effect on the onset of frailty and survival, discovering that the metabolite promotes longer, healthier life associated with a decrease in levels of inflammatory factors. Interestingly the reduction in frailty was more dramatic than the increase in lifespan, leading us to propose that CaAKG compresses morbidity.

cell biology↗