Jia-Rong Wu | PubMed Health

PubMed2026

Genome-wide identification and functional validation of asparagine synthetase genes (NtASNs) in Nicotiana tabacum.

Asparagine (Asn) is pivotal for plant nitrogen (N) metabolism and plays indispensable roles in plant growth, development, and stress tolerance. However, the systematic characteristics and core functions of asparagine synthetase genes (NtASNs) in tobacco remain unclear. Through a comprehensive genome-wide investigation, nine members of the NtASN gene family were identified. Subsequent CRISPR/Cas9-mediated knockout and overexpression assays of these NtASN genes revealed that NtASN1e, NtASN2a, and NtASN2b are the core genes responsible for Asn biosynthesis in tobacco. Their knockout reduced asparagine synthetase activity and Asn content, delayed seed germination by 2-3 days, and displayed elevated oxidative injury when exposed to salinity conditions. In contrast, overexpression of these genes elevated Asn accumulation. Subcellular localization analysis indicated that NtASN1e was localized to both the cytoplasm and chloroplasts, whereas NtASN2a exhibited dual localization in the cytoplasm and endoplasmic reticulum, and NtASN2b was mainly localized in the cytoplasm. This study systematically clarifies the evolutionary characteristics and core functions of the NtASN gene family and provides candidate genes for optimizing nitrogen metabolism and improving salt-stress adaptation in tobacco. These findings hold important practical significance for molecular breeding and product quality improvement in industrial crops.

Nicotiana↗

PubMed2025

Alterations of gut microbiome in chronic rhinosinusitis: insights from a mendelian randomization study.

OBJECTIVE: Gut microbiome dysbiosis is associated with various diseases. Causal association between Chronic Rhinosinusitis (CRS) and gut microbiome is yet unknown. This study aimed to investigate the potential causal relationship between CRS and gut microbiome dysbiosis. METHODS: We used Genome-Wide Association Study (GWAS) data from FinnGen database for CRS. The Dutch Microbiome Project study provided data on gut microbiota species. A total of 334,182 individuals were included. Two-sample bidirectional Mendelian Randomization (MR) analysis was used to investigate causal relationship between CRS and gut microbiome. The main methods of evaluation were Inverse Variance Weighting (IVW), weighted median, weighted mode, and MR-Egger regression. Sensitivity analyses were performed to assess heterogeneity and pleiotropy. RESULTS: Forward MR analysis indicated CRS is potentially linked to decreased risk of Haemophilus parainfluenzae (OR = 0.79, 95% CI 0.66‒0.94, p = 0.009) and increased risk of Bilophila's (OR = 1.14, 95% CI 1.02-1.27, p = 0.023) within the gut. Reduced risks in gut microbiota-related pathways like UDP-N-acetyl-d-glucosamine biosynthesis I (OR = 0.85, 95% CI 0.77‒0.94, p = 0.002) and increased risk in pathway NAD biosynthesis I from aspartate (OR = 1.14, 95% CI 1.03-1.27, p = 0.010) were also linked to CRS. Reverse MR analyses, we obtained no positive results (p > 0.05/412). CONCLUSION: This study reveals CRS exerts a causal impact on shifts within the composition of the gut microbiome and also links to the changes of gut microbiota-related metabolic pathways. The risk of changes in gut microbiota should be of greater concern in patients with CRS than in the general population. LEVEL OF EVIDENCE: Mendelian Randomized (MR) studies are second only to randomized controlled trials in terms of the level of evidence.

Humans↗