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Chitinase genes, as a class of cell wall hydrolases, are essential for the development and pathogenesis of Fusarium oxysporum f.sp. vasinfectum (F. ox) in cotton, but related research focused on chitinase genes are limited. This study explored two island cotton root secretions from the highly resistant cultivar Xinhai 41 and sensitive cultivar Xinhai 14 to investigate their interaction with F. ox by a weighted correlation network analysis (WGCNA). As a result, two modules that related to the fungal pathogenicity emerged. Additionally, a total of twenty-five chitinase genes were identified. Finally, host-induced gene silencing (HIGS) of FoChi20 was conducted, and the cotton plants showed noticeably milder disease with a significantly lower disease index than the control. This study illuminated that chitinase genes play crucial roles in the pathogenicity of cotton wilt fungi, and the FoChi20 gene could participate in the pathogenesis of F. ox and host–pathogen interactions, which establishes a theoretical framework for disease control in Sea Island cotton. [ABSTRACT FROM AUTHOR]

Chromatin remodelers are essential for regulating plant growth, development, and responses to environmental stresses. HIT4 (HEAT-INTOLERANT 4) is a novel stress-induced chromatin remodeling factor that has been less studied in abiotic stress and stress resistance, particularly in cotton. In this study, we conducted a comprehensive analysis of the members of the HIT4 gene family in Gossypium hirsutum using bioinformatics methods, including phylogenetic relationships, gene organization, transcription profiles, phylogenetic connections, selection pressure, and stress response. A total of 18 HIT4 genes were identified in four cotton species, with six HIT4 gene members in upland cotton. Based on the evolutionary relationships shown in the phylogenetic tree, the 18 HIT4 protein sequences were classified into four distinct subgroups. Furthermore, we conducted chromosome mapping to determine the genomic locations of these genes and visually represented the structural characteristics of HIT4 in G. hirsutum. In addition, we predicted the regulatory elements in HIT4 in G. hirsutum and conducted an analysis of repetitive sequences and gene collinearity among HIT4 in four cotton species. Moreover, we calculated the Ka/Ks ratio for homologous genes to assess the selection pressure acting on HIT4. Using RNA-seq, we explored the expression patterns of HIT4 genes in G. hirsutum and Gossypium barbadense. Through weighted gene co-expression network analysis (WGCNA), we found that GHHIT4_4 belonged to the MEblue module, which was mainly enriched in pathways such as DNA replication, phagosome, pentose and glucuronate interconversions, steroid biosynthesis, and starch and sucrose metabolism. This module may regulate the mechanism of upland cotton resistance to Verticillium wilt through DNA replication, phagosome, and various metabolic pathways. In addition, we performed heterologous overexpression of GH_D11G0591 (GHHIT4_4) in tobacco, and the results showed a significant reduction in disease index compared to the wild type, with higher expression levels of disease resistance genes in the transgenic tobacco. After conducting a VIGS (virus-induced gene silencing) experiment in cotton, the results indicated that silencing GHHIT4_4 had a significant impact, the resistance to Verticillium wilt weakened, and the internode length of the plants significantly decreased by 30.7% while the number of true leaves increased by 41.5%. qRT-PCR analysis indicated that GHHIT4_4 mainly enhanced cotton resistance to Verticillium wilt by indirectly regulating the PAL, 4CL, and CHI genes. The subcellular localization results revealed that GHHIT4_4 was predominantly distributed in the mitochondria and nucleus. This study offers preliminary evidence for the involvement of the GHHIT4_4 in cotton resistance to Verticillium wilt and lays the foundation for further research on the disease resistance mechanism of this gene in cotton. [ABSTRACT FROM AUTHOR]

Despite its low transfer efficiency, suicide gene therapy with HSV-TK is known for its bystander killing effect. The connexin-based gap junction is believed to mediate the bystander effect. Recently, we found that resveratrol, a polyphenol compound, increased the expression of Cx26 and Cx43, which are connexins and important constituents of gap junctions, in murine hepatoma cells. Hypothetically, the resveratrol-induced upregulation of gap junctions may improve the bystander effect that HSV-TK/GCV has on hepatoma cells. Our present investigation revealed that resveratrol could enhance intercellular communication at the gap junctions in CBRH7919 hepatoma cells and thereby enhance the bystander killing effect of GCV on CBRH7919TK cells. However, inhibition of gap junction using its long-term inhibitor alpha-glycyrrhetinic acid had a negative influence on the bystander effect of gene therapy with HSV-TK/GCV. In addition, combined resveratrol and GCV treatment in tumor-bearing mice with CBRH7919TK and CBRH7919WT cells at a ratio of 2:3 resulted in a significant decrease in the volume and weight of the tumor in comparison to GCV or only resveratrol. The present results demonstrate that resveratrol can enhance the bystander effect exerted by the HSV-TK/GCV system by enhancing connexin-mediated gap junctional communication. [ABSTRACT FROM AUTHOR]

Importance: Persisting or new thrombi in the distal arteries and the microcirculation have been reported to limit the benefits of successful endovascular thrombectomy for patients with acute ischemic stroke. It remains uncertain whether intra-arterial thrombolysis by urokinase following near-complete to complete reperfusion by thrombectomy improves outcomes among patients with ischemic stroke due to large vessel occlusion., Objective: To assess the efficacy and adverse events of intra-arterial urokinase after near-complete to complete reperfusion by thrombectomy for acute ischemic stroke due to large vessel occlusion., Design, Setting, and Participants: This investigator-initiated, randomized, open-label, blinded-end point trial was implemented at 35 hospitals in China, enrolling 535 patients with proximal intracranial large vessel occlusion presenting within 24 hours of time last known well, who achieved near-complete or complete reperfusion by endovascular thrombectomy and did not receive intravenous thrombolysis prior to the procedure. Recruitment took place between November 15, 2022, and March 29, 2024, with final follow-up on July 4, 2024., Interventions: Eligible patients were randomly assigned to the intra-arterial urokinase group (a single dose of intra-arterial 100 000 IU urokinase injected in the initial target territory; n = 267) or control group (without intra-arterial thrombolysis; n = 267)., Main Outcomes and Measures: The primary efficacy outcome was the percentage of patients achieving survival without disability (modified Rankin Scale score of 0 or 1) at 90 days. The primary safety outcomes were mortality at 90 days and incidence of symptomatic intracranial hemorrhage within 48 hours., Results: A total of 535 patients were enrolled (median age, 69 years; 223 [41.8%] female) and 532 (99.6%) completed the trial. The percentage of patients with survival without disability at 90 days was 45.1% (120/266) in the intra-arterial urokinase group and 40.2% (107/266) in the control group (adjusted risk ratio, 1.13 [95% CI, 0.94-1.36]; P = .19). Mortality at 90 days (18.4% vs 17.3%, respectively; adjusted hazard ratio, 1.06 [95% CI, 0.71-1.59]; P = .77) and incidence of symptomatic intracranial hemorrhage (4.1% vs 4.1%, respectively; adjusted risk ratio, 1.05 [95% CI, 0.45-2.44]; P = .91) were not significantly different between groups., Conclusions and Relevance: Among patients with acute ischemic stroke due to large vessel occlusion, adjunct intra-arterial urokinase after near-complete to complete reperfusion by endovascular thrombectomy did not significantly increase the likelihood of survival without disability at 90 days., Trial Registration: ChiCTR.org.cn Identifier: ChiCTR2200065617.