Biomedical subjects

Liangbiao Chen

Publications and source records attributed to Liangbiao Chen.

3 recordsLinked to original sources

PubMed2026

Screening for dual sgRNAs with comparable indel efficiencies enhances CRISPR-mediated large-fragment deletion.

CRISPR-mediated large-fragment deletion provides a powerful approach for gene clusters, noncoding regions and structural variants, but its broader application is limited by low and variable deletion efficiency. Here, we systematically designed and evaluated 78 sgRNAs targeting nine representative gene clusters (ttn.1-ttn.2 cluster, 7 hox clusters and nppb-nppa cluster), containing 31 large fragments (5 kb-340 kb) to investigate the determinants of deletion efficiency. We found two key rules for achieving high deletion efficiency: (i) using dual sgRNAs with similar indel efficiencies, and (ii) applying a single sgRNA pair rather than multiple sgRNAs. Based on those rules, a 340 kb deletion is detected in the progenies of 95% of founders. Whereas the deletion size showed no significant linear correlation with deletion efficiency within the tested range. Implementing these rules resulted in an average of 70% of founders transmitting deletions across all tested sgRNA pairs. Therefore, screening sgRNAs can effectively enhance CRISPR utility in deletions, thereby facilitating the application of genomic manipulation in vertebrates and other species.

CRISPR↗

PubMed2026

Impaired leptin A signaling disrupts hepatic lipid metabolism and growth in female medaka (Oryzias latipes).

Leptin is a central regulator of appetite and energy metabolism in vertebrates, and its deficiency in mammals typically results in hyperphagia and severe obesity. In fish, however, the physiological roles of leptin remain less clearly defined, partly due to the whole genome duplication (WGD) and divergent expression patterns. In this study, we generated a leptin A (lepa) loss-of-function mutant in medaka (Oryzias latipes) using CRISPR/Cas9 to investigate the function of leptin signaling. Phenotypic analysis revealed that female homozygous mutants exhibited significantly reduced body length and body weight compared with wild-type females, indicating growth impairment. Unexpectedly, despite their lean phenotype, the female mutants developed pronounced hepatic steatosis accompanied by the formation of spongiosis hepatis structures, while no obvious fibrosis was detected. To explore the molecular mechanisms underlying these abnormalities, transcriptomic profiling of mutant livers was performed. Differentially expressed genes were significantly enriched in pathways related to lipid metabolism, including Fatty acid metabolism and PPAR signaling pathway, suggesting a potential reduction in hepatic fatty acid β-oxidation capacity. In addition, genes involved in endoplasmic reticulum stress, autophagy, and apoptosis were altered, indicating transcriptional changes in cellular stress-response pathways under leptin A deficiency. Together, these findings suggest that leptin A may play an important role in coordinating growth and hepatic lipid metabolism in medaka and highlight potential differences in leptin-mediated metabolic regulation between fish and mammals.

Animals↗

PubMed2025

Adaptive Evolution for Freshwater Adaptation in Coilia nasus by Directional Selection on Osmoregulation Genes.

The molecular mechanisms underlying the adaptation to freshwater habitats in fish of marine origin remain unclear. Grenadier anchovies, such as Coilia nasus, originate from marine environments and include both anadromous and freshwater-resident conspecifics, making them ideal for studying adaptive evolution from marine to freshwater habitats. We conducted a comparative population genomic and transcriptome analysis of two distinct C. nasus lineages, one anadromous and the other freshwater-resident, collected from mainstream and estuarine regions of the Yangtze River, China. By genome-wide genotyping of the anadromous and the freshwater-resident populations, we observed significant divergence in osmoregulation, energy metabolism, and immune response pathways associated with ecological adaptation and energy expenditure for migration. Some ion transport genes such as CAMK1, ATP1α3, KCNJ1 and SLC30A2 were identified that may contribute to freshwater adaptation. Notably, numerous mineralocorticoid signalling genes (e.g., NR3C2, SGK1, ATP1α3, KCNJ1) exhibit dynamic change between the anadromous and freshwater populations, suggesting an important role for the hormone cortisol in regulating salinity acclimation in euryhaline fish. Among these genes, the ion channel ATP1α3 experienced adaptive amino acid substitutions (Val317Ile and Thr329Ser), which appear to be evolutionary hotspots across migratory species based on ortholog comparisons. These variants may facilitate sodium/potassium transport and highlight salinity tolerance as a key driver of divergence in anadromous fish transitioning to freshwater. These results enhance our understanding of the genetic basis underlying freshwater adaptation for an anadromous fish across osmotic boundaries.

Animals↗