Fusarium sacchari and Fusarium andiyazi are two devastating sugarcane pathogens that cause pokkah boeng disease (PBD) in China. RNA_Seq was conducted to identify mycoviruses in F. sacchari and F. andiyazi isolates collected from PBD symptom-showing sugarcane plants across China. Fifteen isolates with a normal, debilitated, or abnormal phenotype in colony morphology were screened out for the existence of dsRNA from 104 Fusarium isolates. By sequencing the mixed pool of dsRNA from these Fusarium isolates, a total of 26 contigs representing complete or partial genome sequences of ten mycoviruses and their strains were identified, including one virus belonging to Hypoviridae, two mitoviruses with seven strains belonging to Narnaviridae, one virus of Chrysoviridae, and one alphavirus-like virus. RT-PCR amplification with primers specific to individual mycoviruses revealed that mitoviruses were the most prevalent and the alphavirus-like virus and chrysovirus were the least prevalent. In terms of host preference, more mitoviruses were found in F. andiyazi than in F. sacchari. Fusarium sacchari hypovirus 1 with a 13.9 kb genome and a defective genome of 12.2 kb, shares 54% identity at the amino acid level to the Wuhan insect virus 14, which is an unclassified hypovirus identified from insect meta-transcriptomics. The alphavirus-like virus, Fusarium sacchari alphavirus-like virus 1 (FsALV1), seemed to hold a distinct status amid fungal alphavirus-like viruses, with the highest identity of 27% at the amino acid level to Sclerotium rolfsii alphavirus-like virus 3 and 29% to a hepevirus, Ferret hepatitis E virus. While six of the seven mitoviruses shared 72–94% identities to known mitoviruses, Fusarium andiyazi mitovirus 2 was most similar to Alternaria brassicicola mitovirus with an identity of only 49% between the two viruses. Transmission of FsALV1 and Fusarium sacchari chrysovirus 1 (FsCV1) from F. sacharri to F. commune was observed and the characterization of the four-segment dsRNA chrysovirus was performed with aid of electron microscopy and analysis of the encapsidated RNAs. These findings provide insight into the diversity and spectrum of mycoviruses in PBD pathogens and should be useful for exploring agents to control the disease.

The presence of nonalcoholic fatty liver disease (NAFLD) is a strong risk predictor for type 2 diabetes (T2D). A reduction in sex hormone-binding globulin (SHBG) is associated with NAFLD. Low SHBG is also associated with insulin resistance (IR). However, very limited data are available for the association of SHBG and IR in patients with NAFLD. The study aims to clarify the association between SHBG and IR in patients with NAFLD. In this cross-sectional study, 334 men with NAFLD were recruited. SHBG, total testosterone, free testosterone, total cholesterol, triglyceride, insulin, and glucose concentrations were measured. Homeostatic model assessment (HOMA)-IR and HOMA-β were calculated. Spearman’s correlations and multiple linear regressions were used to analyze the association between SHBG and IR. Men with moderate-severe NAFLD had higher waist circumference, BMI, total cholesterol, triglyceride, insulin, HOMA-IR, HOMA-β, and free testosterone, but lower SHBG than the mild NAFLD. The moderate-severe NAFLD group exhibited higher HOMA-IR (2.38±1.35 vs. 4.16±2.84, p<0.001) and lower SHBG (25.89±11.89 vs. 30.13±12.97 nmol/l, p<0.001) than the other group. SHBG value was negatively correlated with insulin, and HOMA-IR, but was not significantly correlated with glucose and testosterone. The multiple linear regression analysis showed that SHBG was significantly associated with insulin (β=− 0.241, p<0.001), and HOMA-IR (β=− 0.229, p<0.001), even adjusting for potential confounders. In conclusion, low serum SHBG is associated with IR in men with NAFLD. ^* These authors contributed equally to this work

Chrysoviruses are isometric virus particles (35–50 nm in diameter) with a genome composed of double-stranded RNAs (dsRNA). These viruses belonged to the Chrysoviridae family, named after the first member isolated from Penicillium chrysogenum. Phylogenetic classification has divided the chrysoviruses into Alphachrysovirus and Betachrysovirus genera. Currently, these chrysoviruses have been found to infect many fungi, including Fusarium species, and cause changes in the phenotype and decline in the pathogenicity of the host. Thus, it is a microbial resource with great biocontrol potential against Fusarium species, causing destructive plant diseases and substantial economic losses. This review provides a comprehensive overview of three chrysovirus isolates (Fusarium graminearum virus 2 (FgV2), Fusarium graminearum virus-ch9 (FgV-ch9), and Fusarium oxysporum f. sp. dianthi mycovirus 1 (FodV1)) reported to decline the pathogenicity of Fusarium hosts. It also summarizes the recent studies on host response regulation, host RNA interference, and chrysovirus transmission. The information provided in the review will be a reference for analyzing the interaction of Fusarium species with chrysovirus and proposing opportunities for research on the biocontrol of Fusarium diseases. Finally, we present reasons for conducting further studies on exploring the interaction between chrysoviruses and Fusarium and improving the accumulation and transmission efficiency of these chrysoviruses.