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Knee Osteoarthritis (KOA) is characterized by phenotypic alterations, apoptosis, and the breakdown of the extracellular matrix (ECM) in the superficial articular cartilage cells. The inflammatory response activates the Endoplasmic Reticulum Stress (ERS) signaling pathway, which plays a critical role in the pathophysiology and progression of KOA. Chondrocytes stimulated by thapsigargin(TG)exhibit heightened ERS and significantly increase the expression of ERS-associated proteins. Key mediators of ERS-induced apoptosis include X-box-binding protein 1(XBP1), elevated levels of the protein transport protein Sec61 subunit (SEC61), and C/EBP homologous protein (CHOP).While the precise mechanism of action of Guilu Erxian Glue (GEG), a medication commonly used in the clinical treatment of KOA, remains to be fully elucidated, our research has shown that GEG mitigates the imbalance between ECM synthesis and degradation, as well as chondrocyte apoptosis resulting from ERS. This effect is likely achieved through the suppression of the Activating Transcription Factor 6 (ATF6)/Glucose-Regulatory Protein 78 (GRP78)/CHOP signaling pathway.In summary,our research results indicate that GEG can activate the ATF6/GRP78/CHOP signaling pathway to restore endoplasmic reticulum (ER) homeostasis in chondrocytes, thereby reducing chondrocyte apoptosis and ultimately promoting the balance between ECM synthesis and degradation.

Abstract Fusarium head blight (FHB) is one of the most destructive wheat diseases worldwide. To understand the impact of human migration and changes in agricultural practices on crop pathogens, here population genomic analysis with 245 representative strains from a collection of 4,427 field isolates of Fusarium asiaticum, the causal agent of FHB in Southern China is conducted. Three populations with distinct evolution trajectories are identifies over the last 10,000 years that can be correlated with historically documented changes in agricultural practices due to human migration caused by the Southern Expeditions during the Jin Dynasty. The gradual decrease of 3ADON‐producing isolates from north to south along with the population structure and spore dispersal patterns shows the long‐distance (>250 km) dispersal of F. asiaticum. These insights into population dynamics and evolutionary history of FHB pathogens are corroborated by a genome‐wide analysis with strains originating from Japan, South America, and the USA, confirming the adaptation of FHB pathogens to cropping systems and human migration.

Fusarium asiaticum is one of the pivotal members of the Fusarium graminearum species complex (FGSC) causing Fusarium head blight (FHB) on wheat, barley and rice in large parts of Asia. Besides resulting in yield losses, FHB also causes the accumulation of mycotoxins such as nivalenol (NIV) and deoxynivalenol (DON). The aim of this study was to conduct population studies on F. asiaticum from Southern China through mitochondrial genome analyses. All strains were isolated from wheat or rice from several geographic areas in seven provinces in Southern China. Based on geographic location and host, 210 isolates were selected for next generation sequencing, and their mitogenomes were assembled by GRAbB and annotated to explore the mitochondrial genome variability of F. asiaticum. The F. asiaticum mitogenome proves extremely conserved and variation is mainly caused by absence/presence of introns harboring homing endonuclease genes. These variations could be utilized to develop molecular markers for track and trace of migrations within and between populations. This study illustrates how mitochondrial introns can be used as markers for population genetic analysis. SNP analysis demonstrate the occurrence of mitochondrial recombination in F. asiaticum as was previously found for F. oxysporum and implied for F. graminearum. Furthermore, varying degrees of genetic diversity and recombination showed a high association with different geographic regions as well as with cropping systems. The mitogenome of F. graminearum showed a much higher SNP diversity while the interspecies intron variation showed no evidence of gene flow between the two closely related and sexual compatible species.

In recent years, Fusarium head blight (FHB) outbreaks have occurred much more frequently in China. The reduction of burning of the preceding crop residues is suggested to contribute to more severe epidemics as it may increase the initial inoculum. In this study, a large number of Fusarium isolates was collected from blighted wheat spikes as well as from rice stubble with perithecia originating from nine sampling sites in five provinces in Southern China. Fusarium asiaticum dominated both wheat and rice populations, although rice populations showed a higher species diversity. Chemotype analysis showed that rice is the preferred niche for NIV mycotoxin producers that were shown to be less virulent on wheat. In contrast, 3ADON producers are more prevalent on wheat and in wheat producing areas. The 3ADON producers were shown to be more virulent on wheat, revealing the selection pressure of wheat on 3ADON producers. For the first time, members of the Incarnatum-clade of Fusarium Incarnatum-Equiseti Species Complex (FIESC) were found to reproduce sexually on rice stubble. The pathogenicity of FIESC isolates on wheat proved very low and this may cause the apparent absence of this species in the main wheat producing provinces. This is the first report of the Fusarium population structure including rice stubble as well as a direct comparison with the population on wheat heads in the same fields. Our results confirm that the perithecia on rice stubble are the primary inoculum of FHB on wheat and that cropping systems affect the local Fusarium population.