Biology subjects

Wang, E. X.

Publications and source records attributed to Wang, E. X..

3 recordsLinked to original sources

bioRxiv2026

Glucagon-like peptide-1 receptor agonist, semaglutide, attenuates intravenous self-administration of fentanyl in female rats

Current treatments for opioid use disorder (OUD) have major barriers to access. As such, researching new potential therapies for OUD is important to public health. Previous research has implicated glucagon-like peptide-1 (GLP-1) receptor agonists in decreasing the use of addictive substances by animals. In this study, female Wistar rats (N=32) were surgically implanted with jugular catheters and trained to self-administer fentanyl at a fixed-ratio 1 (FR1) schedule of reinforcement for 21 sessions under short- (ShA; 1 hour) or long-access (LgA; 8 hours) conditions. Next, the animals received injections of semaglutide (0.1 mg/kg, s.c.) or saline (0.9% NaCl, s.c.) prior to another FR1 session. The animals underwent a progressive ratio (PR) schedule of reinforcement while receiving saline (i.v.) or fentanyl (0.625-10 {micro}g/kg/inf, i.v.) and semaglutide (0.1 mg/kg, s.c.) or saline (s.c.). Next, the animals underwent a semaglutide (0-0.1 mg/kg, s.c.) dose response procedure at FR1 and a single dose of fentanyl (2.5 {micro}g/kg/inf, i.v.). Following drug discontinuation, spontaneous locomotor activity and withdrawal-like symptoms were measured. Semaglutide dose-dependently decreased fentanyl rewards under ShA and LgA conditions (p<0.05). Under a PR, semaglutide significantly decreased breakpoint (p<0.05), suggesting semaglutide decreases motivation to self-administer fentanyl. Semaglutide-treated ShA animals displayed significantly less withdrawal-like behavior (p<0.05) but not LgA animals. Overall, these findings suggest semaglutide may modulate motivation to seek opioid reward and could be useful in the development of pharmacotherapies to address OUD.

pharmacology and toxicology↗

bioRxiv2025

Inferring the regulation dynamics of oscillatorynetworks from scRNA-seq data

Oscillatory processes such as the cell cycle play critical roles in cell fate determination and disease development. Yet, most current gene regulatory network (GRN) inference methods are based on gene-gene correlations or temporal progression, not adequately accounting for the recurrence in cyclic processes. We hypothesize that constraining the continuous ordering of relative positions along the cell cycle can enhance GRN inference accuracy of cell cycle regulation. To test performance, we evaluated eight representative methods and applied three of them to a mouse retinal progenitor single-cell gene expression dataset [1]. Incorporating cell cycle positions inferred by Tricycle [2] led to significant improvements compared against using experimental times, particularly for early progenitor cells that been hypothesized to be more intrinsically driven by cell cycle regulation. These findings highlight the promise of integrating oscillatory processes into causal inference frameworks to advance our understanding of gene regulation.

bioinformatics↗

bioRxiv2023

Mycobacterium smegmatis NucS-promoted DNA Mismatch Repair involves limited resection by a 5'-3' exonuclease and is independent of homologous recombination and NHEJ

The MutSL mismatch repair (MMR) system in bacteria and eukaryotes correct mismatches made at the replication fork to maintain genome stability. A novel MMR system is represented by the EndoMS/NucS endonuclease from actinobacterium Corynebacterium glutamicum, which recognizes mismatched substrates in vitro and creates dsDNA breaks at the mismatch. In this report, a genetic analysis shows that an M. smegmatis {Delta}nucS strain could be complemented by expression of wild type NucS protein, but not by one deleted of its last five amino acids, a region predicted to be critical for binding to the {beta}-clamp at the replication fork. Oligo-recombineering was then leveraged to deliver defined mismatches to a defective hygromycin resistance gene on the M. smegmatis chromosome. We find that NucS recognizes and repairs G-G, G-T, and T-T mismatches in vivo, consistent with the recognition of these same mismatches in C. glutamicum in vitro, as well as mutation accumulation studies done in M. smegmatis. Finally, an assay that employs an oligo that promotes the generation of two mismatches in close proximity on the chromosome shows that a NucS-promoted cut is processed by a 5-3 exonuclease and that NucS-promoted MMR is independent of both homologous recombination and non-homologous end-joining.

genetics↗