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Simple Summary: Epigenetic modification plays an important regulatory role in breast cancer progression. However, the relationship between epigenetic modification with tumor metabolism has not yet been fully elucidated. PDK1, as a key enzyme in glucose metabolism, mediates multiple tumors development. But, the mechanism of epigenetic modification in regulating PDK1 remains unclear in breast cancer. Here, we demonstrated that HDAC2 and EZH2 upregulated PDK1 expression through inhibiting miR-148a. Importantly, miR-148a targeting PDK1 regulated breast cancer cells glycolysis, invasion, epithelial-mesenchymal transition (EMT) and Adriamycin resistance. Our results suggested that the HDAC2/EZH2/miR-148a/PDK1 axis may be a promising potential therapeutic strategy. Background: Breast cancer has one of highest morbidity and mortality rates for women. Abnormalities regarding epigenetics modification and pyruvate dehydrogenase kinase 1 (PDK1)-induced unusual metabolism contribute to breast cancer progression and chemotherapy resistance. However, the role and mechanism of epigenetic change in regulating PDK1 in breast cancer remains to be elucidated. Methods: Gene set enrichment analysis (GSEA) and Pearson's correlation analysis were performed to analyze the relationship between histone deacetylase 2 (HDAC2), enhancer of zeste homologue 2 (EZH2), and PDK1 in database and human breast cancer tissues. Dual luciferase reporters were used to test the regulation between PDK1 and miR-148a. HDAC2 and EZH2 were found to regulate miR-148a expression through Western blotting assays, qRT-PCR and co-immunoprecipitation assays. The effects of PDK1 and miR-148a in breast cancer were investigated by immunofluorescence (IF) assay, Transwell assay and flow cytometry assay. The roles of miR-148a/PDK1 in tumor growth were investigated in vivo. Results: We found that PDK1 expression was upregulated by epigenetic alterations mediated by HDAC2 and EZH2. At the post-transcriptional level, PDK1 was a new direct target of miR-148a and was upregulated in breast cancer cells due to miR-148a suppression. PDK1 overexpression partly reversed the biological function of miR-148a—including miR-148a's ability to increase cell sensitivity to Adriamycin (ADR) treatment—inhibiting cell glycolysis, invasion and epithelial–mesenchymal transition (EMT), and inducing apoptosis and repressing tumor growth. Furthermore, we identified a novel mechanism: DNMT1 directly bound to EZH2 and recruited EZH2 and HDAC2 complexes to the promoter region of miR-148a, leading to miR-148a downregulation. In breast cancer tissues, HDAC2 and EZH2 protein expression levels also were inversely correlated with levels of miR-148a expression. Conclusion: Our study found a new regulatory mechanism in which EZH2 and HDAC2 mediate PDK1 upregulation by silencing miR-148a expression to regulate cancer development and Adriamycin resistance. These new findings suggest that the HDAC2/EZH2/miR-148a/PDK1 axis is a novel mechanism for regulating cancer development and is a potentially promising target for therapeutic options in the future. [ABSTRACT FROM AUTHOR]

The volatile profiles of fruit peels and juice sacs from 108 citrus accessions representing seven species were analyzed. Using GC–MS 162 and 107 compounds were determined in the peels and juice sacs, respectively. In the peels, monoterpene alcohols were accumulated in loose-skin mandarins; clementine tangerines and papedas were rich in sesquiterpene alcohols, sesquiterpenes, monoterpene alcohols and monoterpene aldehydes. β -pinene and sabinene were specifically accumulated in 4 of 5 lemon germplasms. Furthermore, concentrations of 34 distinctive compounds were selected to best represent the volatile profiles of seven species for HCA analysis, and the clustering results were in agreement with classic citrus taxonomy. Comparison of profiles from different growing seasons and production areas indicated that environmental factors play important roles in volatile metabolism. In addition, a few citrus germplasms that accumulated certain compounds were determined as promising breeding materials. Notably, volatile biosynthesis via MVA pathway in C. ichangensis ‘Huaihua’ was enhanced. [ABSTRACT FROM AUTHOR]

Irrigation, fertilization, and variety are important factors affecting potato production in northwest China. Field experiments (2021 and 2022) were performed to investigate the effects of irrigation and fertilization on the plant growth and soil microbial population of different potato varieties. Three irrigation levels were used, i.e., 100% ETc (W1), 80% ETc (W2), and 60% ETc (W3), with ETc standing for crop evapotranspiration. Three fertilization levels were used (N-P-K), i.e., 240-120-300 kg ha−1 (F1), 180-90-225 kg ha−1 (F2), and 120-60-150 kg ha−1 (F3). Three variety types were used, i.e., Feiurita (V1), Longshu 7 (V2), and Qingshu 9 (V3). These factors significantly influenced tuber yield (TY), net income (NI), and water productivity (WP). TY, NI, WP, total nitrogen accumulation (TNA), and nitrogen use efficiency (NUE) peaked at F2. Fertilization significantly impacted soil bacteria quantity (SBQ), fungi quantity (SFQ), and actinomycetes quantity (SAQ). TY, NI, SBQ, SFQ, and SAQ were highest at W2. Soil microbial population was strongly correlated with TY, NI, WP, TNA, and NUE. Comprehensively, this study suggests that irrigation that is varied from 248 to 266 mm, and fertilization (N-P-K) that is varied from 149.09-74.55-186.36 to 212.73-106.36-265.91 kg ha−1 can promote the potato industry's sustainable development and provide important references for the optimal field management of potato cultivation in northwest China. [ABSTRACT FROM AUTHOR]

Kiwifruit contains abundant nutritive compounds and is highly favored by the consumers worldwide. Therefore, detailed metabolic profiling is important to provide theoretic basis for the improvement of kiwifruit quality. In this study, the levels of volatiles, carotenoids, and mineral elements in the flesh of 17 kiwifruit accessions were evaluated. Acids and esters were the main volatiles in kiwifruit. During these 17 kiwifruit accessions, "Chenhong," three "Jinyan," and two "Guichang" germplasms were specifically rich in aromatic esters, which might be associated with their special taste. The main carotenoids were lutein, β‐carotene, and zeaxanthin, and their levels were also genotype specific, with the green‐fleshed "Guichang" having the highest level of carotenoids, and red‐fleshed "Fuhong" and "Chenhong" being rich in zeaxanthin. Partial correlation analysis showed that the contents of some mineral elements were significantly correlated with those of specific volatiles and carotenoids, indicating the impacts of mineral elements on the accumulation of volatiles and carotenoids in the kiwifruit flesh. These results indicated that the contents of carotenoids and volatiles seemed to be affected by mineral elements and also provided a new potential method for improving fruit flavor quality in production. [ABSTRACT FROM AUTHOR]

Background: Tea plant is one of the most important non-alcoholic beverage crops worldwide. While potassium (K+) is an essential macronutrient and greatly affects the growth and development of plants, the molecular mechanism underlying K+ uptake and transport in tea plant root, especially under limited-K+ conditions, is still poorly understood. In plants, HAK/KUP/KT family members play a crucial role in K+ acquisition and translocation, growth and development, and response to stresses. Nevertheless, the biological functions of these genes in tea plant are still in mystery, especially their roles in K+ uptake and stress responses. Results: In this study, a total of 21 non-redundant HAK/KUP/KT genes (designated as CsHAKs) were identified in tea plant. Phylogenetic and structural analysis classified the CsHAKs into four clusters (I, II, III, IV), containing 4, 8, 4 and 5 genes, respectively. Three major categories of cis-acting elements were found in the promoter regions of CsHAKs. Tissue-specific expression analysis indicated extremely low expression levels in various tissues of cluster I CsHAKs with the exception of a high root expression of CsHAK4 and CsHAK5, a constitutive expression of clusters II and III CsHAKs, and a moderate cluster IV CsHAKs expression. Remarkably, the transcript levels of CsHAKs in roots were significantly induced or suppressed after exposure to K+ deficiency, salt and drought stresses, and phytohormones treatments. Also notably, CsHAK7 was highly expressed in all tissues and was further induced under various stress conditions. Therefore, functional characterization of CsHAK7 was performed, and the results demostrated that CsHAK7 locates on plasma membrane and plays a key role in K+ transport in yeast. Taken together, the results provide promising candidate CsHAKs for further functional studies and contribute to the molecular breeding for new tea plants varieties with highly efficient utilization of K+. Conclusion: This study demonstrated the first genome-wide analysis of CsHAK family genes of tea plant and provides a foundation for understanding the classification and functions of the CsHAKs in tea plants. [ABSTRACT FROM AUTHOR]

Background and Aims Fatty acid translocase CD36 (CD36) is a membrane protein with multiple immuno-metabolic functions. Palmitoylation has been suggested to regulate the distribution and functions of CD36, but little is known about its significance in non-alcoholic steatohepatitis (NASH). Methods Human liver tissue samples were obtained from patients undergoing liver biopsy for diagnostic purposes. CD36 knockout mice were injected with lentiviral vectors expressing wild-type CD36 or CD36 with mutated palmitoylation sites. Liver histology, immunofluorescence, mRNA expression profile, subcellular distributions and functions of CD36 protein were assessed. Results The localization of CD36 on the plasma membrane of hepatocytes was markedly increased in patients with NASH compared to patients with normal liver and those with simple steatosis. Increased CD36 palmitoylation and increased localization of CD36 on the plasma membrane of hepatocytes were also observed in livers of mice with NASH. Furthermore, inhibition of CD36 palmitoylation protected mice from developing NASH. The absence of palmitoylation decreased CD36 protein hydrophobicity reducing its localization on the plasma membrane as well as in lipid raft of hepatocytes. Consequently, a lack of palmitoylation decreased fatty acid uptake and CD36/Fyn/Lyn complex in HepG2 cells. Inhibition of CD36 palmitoylation not only ameliorated intracellular lipid accumulation via activation of the AMPK pathway, but also inhibited the inflammatory response through the inhibition of the JNK signaling pathway. Conclusions Our findings demonstrate the key role of palmitoylation in regulating CD36 distributions and its functions in NASH. Inhibition of CD36 palmitoylation may represent an effective therapeutic strategy in patients with NASH. Lay summary Fatty acid translocase CD36 (CD36) is a multifunctional membrane protein which contributes to the development of liver steatosis. In the present study, we demonstrated that the localization of CD36 on the plasma membrane of hepatocytes is increased in patients with non-alcoholic steatohepatitis. Blocking the palmitoylation of CD36 reduces CD36 distribution in hepatocyte plasma membranes and protects mice from non-alcoholic steatohepatitis. The inhibition of CD36 palmitoylation not only improved fatty acid metabolic disorders but also reduced the inflammatory response in vitro and in vivo . The present study suggests that CD36 palmitoylation is important for non-alcoholic steatohepatitis development and inhibition of CD36 palmitoylation could be used to cure non-alcoholic steatohepatitis. [ABSTRACT FROM AUTHOR]

Due to the furanocoumarin compounds in the fruit, the production and consumption of grapefruit have been affected in the past decades since the ‘grapefruit juice effect’ was declared. To provide elite germplasm and obtain knowledge for future citrus breeding programs, the contents of 4 furanocoumarin monomers (FCMs) in the juice sacs from 73 citrus germplasms were evaluated using ultra-performance liquid chromatography. 6′,7′-Dihydroxybergamottin and bergamottin were dominant in all the tested grapefruits, while there were some pomelos with dominant epoxybergamottin, and some with dominant 6′,7′-dihydroxybergamottin and bergamottin. The contents of FCMs were low or below detection in sweet oranges, mandarins, lemons and trifoliate oranges. The results also show that the dominant patterns of FCMs are genotype-related, and crossing and selection are effective approaches to alter FCM profiles in citrus breeding. Furthermore, the contribution of pomelo as a parent to grapefruit regarding their FCM profiles was discussed. [ABSTRACT FROM AUTHOR]

The prevalence of nonalcoholic fatty liver disease (NAFLD) increases with increasing body mass index (BMI). However, approximately 40-50% of obese adults do not develop hepatic steatosis. The level of inflammatory biomarkers is higher in obese subjects with NAFLD compared to BMI-matched subjects without hepatic steatosis. We used a casein injection in high-fat diet (HFD)-fed C57BL/6J mice to induce inflammatory stress. Although mice on a HFD exhibited apparent phenotypes of obesity and hyperlipidemia regardless of exposure to casein injection, only the HFD+Casein mice showed increased hepatic vacuolar degeneration accompanied with elevated inflammatory cytokines in the liver and serum, compared to mice on a normal chow diet. The expression of genes related to hepatic fatty acid synthesis and oxidation were upregulated in the HFD-only mice. The casein injection further increased baseline levels of lipogenic genes and decreased the levels of oxidative genes in HFD-only mice. Inflammatory stress induced both oxidative stress and endoplasmic reticulum stress in HFD-fed mice livers. We conclude that chronic inflammation precedes hepatic steatosis by disrupting the balance between fatty acid synthesis and oxidation in the livers of HFD-fed obese mice. This mechanism may operate in obese individuals with chronic inflammation, thus making them more prone to NAFLD. [ABSTRACT FROM AUTHOR]