UvATG6 Interacts with BAX Inhibitor 1 Proteins and Plays Critical Roles in Growth, Conidiation, and Virulence in Ustilaginoidea virens.

Autophagy and apoptosis are evolutionarily conserved catabolic processes involved in regulating development and cellular homeostasis. Bax inhibitor 1 (BI-1) and autophagy protein 6 (ATG6) perform essential functions in these roles, such as cellular differentiation and virulence in various filamentous fungi. However, the functions of ATG6 and BI-1 proteins in development and virulence in the rice false smut fungus Ustilaginoidea virens are still poorly understood. In this study, UvATG6 was characterized in U. virens. The deletion of UvATG6 almost abolished autophagy in U. virens and reduced growth, conidial production and germination, and virulence. Stress tolerance assays showed that UvATG6 mutants were sensitive to hyperosmotic, salt, and cell wall integrity stresses but were insensitive to oxidative stress. Furthermore, we found that UvATG6 interacted with UvBI-1 or UvBI-1b and suppressed Bax-induced cell death. We previously found that UvBI-1 could suppress Bax-induced cell death and was a negative regulator of mycelial growth and conidiation. Unlike UvBI-1, UvBI-1b could not suppress cell death. UvBI-1b-deleted mutants exhibited decreased growth and conidiation, while the UvBI-1 and UvBI-1b double deletion reduced the phenotype, indicating that UvBI-1 and UvBI-1b antagonistically regulate mycelial growth and conidiation. In addition, the UvBI-1b and double mutants exhibited decreased virulence. Our results provide evidence of the cross talk of autophagy and apoptosis in U. virens and give clues for studying other phytopathogenic fungi. IMPORTANCE Ustilaginoidea virens causes destructive panicle disease in rice, significantly threatening agricultural production. UvATG6 is required for autophagy and contributes to growth, conidiation, and virulence in U. virens. Additionally, it interacts with the Bax inhibitor 1 proteins UvBI-1 and UvBI-1b. UvBI-1 suppresses cell death induced by Bax, unlike UvBI-1b. UvBI-1 negatively regulates growth and conidiation, while UvBI-1b is required for these phenotypes. These results indicate that UvBI-1 and UvBI-1b may antagonistically regulate growth and conidiation. In addition, both of them contribute to virulence. Additionally, our results suggest cross talk between autophagy and apoptosis, contributing to the development, adaptability, and virulence of U. virens.

The mRNA Expression Signature and Prognostic Analysis of Multiple Fatty Acid Metabolic Enzymes in Clear Cell Renal Cell Carcinoma.

Renal cell carcinoma (RCC) is a metabolic disease, and accumulating evidences indicate significant alterations in the cellular metabolism, especial aerobic glycolysis and glutamine metabolism, in RCC. However, fatty acid (FA) metabolism has received less attention, and the mRNA expression pattern and prognostic role of FA metabolic enzymes in clear cell RCC (ccRCC) have not been carefully examined. In the current study, we first investigated the mRNA expression profiles of multiple FA metabolic enzymes, i.e., ACLY, ACC, FASN, SCD, CPT1A, HADHA, HADHB, and ACAT1, in 42 ccRCC and 33 normal kidney tissues using the Oncomine database, validated their mRNA expression profiles using GEPIA resource, then evaluated and validated the prognostic significance of these metabolic enzymes in 530 ccRCC patients using Kaplan-Meier plotter and GEPIA analyses respectively. The Oncomine and GEPIA confirmed higher ACLY, SCD, and lower ACAT1 mRNA expression in ccRCC than normal tissues (P<0.05). And further prognostic analysis displayed that overexpression of the some FA anabolic enzymes (FASN) was correlated to poor overall survival (OS), while overexpression of the FA catabolic enzymes (CPT1A, HADHA, HADHB, and ACAT1) was correlated to favorable OS in ccRCC patients. In conclusion, multiple FA metabolic enzymes, such as FASN, HADHA, and ACAT1, were potential prognostic markers of ccRCC, which implied alterations in FA metabolism might be involved in ccRCC tumorigenesis and progression.

Preparation of nitrogen-doped porous carbons for high-performance supercapacitor using biomass of waste lotus stems.

In this study, advanced nitrogen-doped porous carbon materials for supercapacitor was prepared using low-cost and environmentally friendly waste lotus stems (denoted as LS-NCs). Nitrogen in the surface functionalities of LS-NCs was investigated using X-ray photoelectron spectroscopy analysis. The sum of pyridine nitrogen (N-6) and pyrrolic/pyridinic (N-5) contents accounted for 94.7% of the total nitrogen and significantly contributed to conductivity. Pore structure and surface area of activated carbons were measured using the Brunauer-Emmett-Teller method. A maximum specific surface area of 1322 m2 g-1 was achieved for LS-NCs. The porous carbons exhibited excellent electrochemical properties with a specific capacitance of 360.5 F g-1 at a current density of 0.5 A g-1 and excellent cycling stability (96% specific capacitance retention after 5000 cycles). The above findings indicate that taking advantage of the unique structure of abundant waste lotus stem provides a low-cost and feasible design for high-performance supercapacitors.