Dual specificity tyrosine phosphorylation regulated kinase 1A, DYRK1A, functions in multiple cellular pathways, including signaling, endocytosis, synaptic transmission, and transcription. Alterations ...in dosage of DYRK1A leads to defects in neurogenesis, cell growth, and differentiation, and may increase the risk of certain cancers. DYRK1A localizes to a number of subcellular structures including vesicles where it is known to phosphorylate a number of proteins and regulate vesicle biology. However, the mechanism by which it translocates to vesicles is poorly understood. Here we report the discovery of TRAF2, an E3 ligase, as an interaction partner of DYRK1A. Our data suggest that TRAF2 binds to PVQE motif residing in between the PEST and histidine repeat domain (HRD) of DYRK1A protein, and mediates K63-linked ubiquitination of DYRK1A. This results in translocation of DYRK1A to the vesicle membrane. DYRK1A increases phosphorylation of Sprouty 2 on vesicles, leading to the inhibition of EGFR degradation, and depletion of TRAF2 expression accelerates EGFR degradation. Further, silencing of DYRK1A inhibits the growth of glioma cells mediated by TRAF2. Collectively, these findings suggest that the axis of TRAF2-DYRK1A-Sprouty 2 can be a target for new therapeutic development for EGFR-mediated human pathologies.
Primary hepatocytes are widely used as a tool for studying metabolic function and regulation in the liver. However, the metabolic properties of primary hepatocytes are gradually lost after isolation. ...Here, we illustrated that fatty acid metabolism is the major compromised metabolic process in isolated primary hepatocytes, along with drastically decreased GSH and ROS content, while lipid peroxidation is increased. Gain- and loss-of-function studies revealed that Slc7a11 expression is critical in maintaining fatty acid metabolism and facilitating hormone-induced fatty acid metabolic events, which is synergistic with dexamethasone treatment. Intriguingly, Slc7a11 expression and dexamethasone treatment cooperatively upregulated AKT and AMPK signaling and mitochondrial complex expression in primary hepatocytes. Furthermore, direct treatment with reduced GSH or inhibition of ferroptosis is sufficient to drive protective effects on fatty acid metabolism in primary hepatocytes. Our results demonstrate that Slc7a11 expression in isolated primary hepatocytes induces GSH production, which protects against ferroptosis, to increase fatty acid metabolic gene expression, AKT and AMPK signaling and mitochondrial function in synergy with dexamethasone treatment, thereby efficiently preserving primary hepatocyte metabolic signatures, thus providing a promising approach to better reserve primary hepatocyte metabolic activities after isolation to potentially improve the understanding of liver biological functions from studies using primary hepatocytes.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Abstract
DYRK1A, dual-specificity tyrosine phosphorylation-regulated kinase 1A, which is linked to mental retardation and microcephaly, is a member of the CMGC group of kinases. It has both ...cytoplasmic and nuclear functions, however, molecular mechanisms of how DYRK1A regulates gene expression is not well understood. Here, we identify two histone acetyltransferases, p300 and CBP, as interaction partners of DYRK1A through a proteomics study. We show that overexpression of DYKR1A causes hyperphosphorylation of p300 and CBP. Using genome-wide location (ChIP-sequencing) analysis of DYRK1A, we show that most of the DYRK1A peaks co-localize with p300 and CBP, at enhancers or near the transcription start sites (TSS). Modulation of DYRK1A, by shRNA mediated reduction or transfection mediated overexpression, leads to alteration of expression of downstream located genes. We show that the knockdown of DYRK1A results in a significant loss of H3K27acetylation at these enhancers, suggesting that DYRK1A modulates the activity of p300/CBP at these enhancers. We propose that DYRK1A functions in enhancer regulation by interacting with p300/CBP and modulating their activity. Overall, DYRK1A function in the regulation of enhancer activity provides a new mechanistic understanding of DYRK1A mediated regulation of gene expression, which may help in better understanding of the roles of DYRK1A in human pathologies.
In China, 45% of adolescents with obesity develop fatty liver disease, a condition that increases the long-term risk of developing cirrhosis and liver cancer. Although the factors triggering ...nonalcoholic fatty liver disease (NAFLD) vary in children, the composition of intestinal microflora has been found to play an increasingly important role. However, evidence is limited on the prevalence of nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH) in Chinese children. Therefore, this study aimed to evaluate the fecal microbiome of Chinese children with NAFLD and further analyze the potential of flora in regulating NAFLD-related symptoms and metabolic functions. Specifically, the study applied a 16S rRNA and metagenomic sequencing to the fecal samples of pediatric patients with NAFLD, NASH, and NAFL, as well as healthy controls, to explore the correlation among NAFLD-related indexes, metabolic pathways, and gut flora. The findings showed that some fecal microbiota had a negative correlation with body mass index, and various NAFLD-related bacteria, including
,
, and
, were detected. Consequently, the study concluded that the variation in gut microbiota might be more important in improving NAFLD/NASH compared with single species, providing a microbiota diagnostic profile of NAFLD/NASH.IMPORTANCEThis study aims to characterize the gut microbiota in Chinese children with nonalcoholic fatty liver disease (NAFLD) through 16S rRNA and metagenomic sequencing. The results highlight the association between fecal microbiota and NAFLD in Chinese children, demonstrating distinct characteristics compared to adults and children from other countries. Based on the sequencing data from our cohort's fecal samples, we propose a microbiota model with a high area under the curve for distinguishing between NAFLD and healthy individuals. Furthermore, our follow-up study reveals that changes in the relative abundance of microbial biomarkers in this model are consistent with variations in patients' body mass index. These findings suggest the potential utility of the microbiota model and microbial biomarkers for diagnosing and treating NAFLD in children.
Soil salinity is a notorious abiotic stress which constrains plant growth and limits crop productivity. Recent advances in phytogenetics especially the discovery of marker-trait association have ...facilitated the efficient selection of stress-tolerant crops. The objective of this study was to evaluate tall fescue (
Festuca arundinacea
Schreb.) accessions growing under salt stress in order to identify salt-tolerant and salt-sensitive genotypes using physiological and molecular markers. The population consisted of 114 diverse tall fescue accessions which were assessed using 99 simple sequence repeat (SSR) markers and five functional physiological traits i.e., turf quality, leaf water content, chlorophyll content, relative growth rate, and evapotranspiration rate. Salinity stress induced great variations among the functional physiological traits and there were significant correlations among them. The population structure analysis revealed two distinct populations, while association mapping between the SSRs and phenotypic traits identified significant associations. In addition, the accessions that maintained relatively higher physiological traits had a significantly lower accumulation of Na
+
and Cl
−
in the roots compared to those whose functional traits declined. We identified six most salt-tolerant accessions due to their high values of physiological parameters and significantly low accumulation of Na
+
and Cl
−
in the roots. Similarly, we identified six accessions we considered to be most salt-sensitive as observed by high Na
+
and Cl
−
accumulation plus a decline in the physiological activities. Our findings are helpful to tall fescue breeders with a goal of producing tall fescue cultivars with enhanced salt tolerance.
Th1/Th2-like cytokine mRNA levels in non-cancerous hepatic tissues from patients with hepatocellular carcinoma (HCC) are associated with metastases and recurrence. This study evaluated the prognostic ...values of intratumoral and peritumoral Th1/Th2 cytokine protein levels in patients with HCC after curative resection.
Two independent cohorts (A and B) of 453 patients with HCC were enrolled. Twelve Th1/Th2 cytokines in tumour and peritumoral hepatic tissues from cohort A (n=192) were quantified with enzyme-linked immunosorbent assays. This cohort was split into training and test sets which were used to identify and verify the prognostic cytokines. The prognostic values of identified cytokines were further validated in cohort B (n=261) using tissue microarray and immunohistochemical staining.
In the training set, higher interleukin (IL)-2 and IL-15 levels in peritumoral liver tissues, but not in tumour tissues, were significantly associated with a decreased incidence of recurrence of intrahepatic tumour and a prolonged overall survival. This association was verified in the testing set and further validated in patients in cohort B. Importantly, this correlation remained significant in patients with early HCC. Univariate and multivariate analyses indicated that the prognostic performance of peritumoral IL-2 (HR for recurrence=0.4, 95% CI 0.3 to 0.6, p<0.0001; HR for death=0.6, 95% CI 0.4 to 0.8, p=0.005) and IL-15 (HR for recurrence=0.7, 95% CI 0.5 to 0.95, p=0.025) was independent of other clinicopathological factors.
Peritumoral IL-2 and IL-15 levels are useful for stratifying patients, even those with early-stage HCC, into subgroups with different prognoses after curative resection.
Cu(i)-Catalyzed diastereoselective carboboration of α-alkyl-substituted α,β-unsaturated carboxylic esters to produce β-boryl-α-quaternary carbon esters was developed. The carbon skeletons of dialkyl ...sulfates, primary allyl halides, and benzyl bromides were transferred to the α-position of the substrates to provide products in moderate to good yields with a diastereoselectivity of >95% in most cases. Substrates bearing a β-(hetero)aryl substituent gave higher diastereoselectivities than those bearing a linear β-alkyl substituent. The crystal structure of the potassium trifluoroborate derivative shows that the reactions probably go through a copper(i) enolate intermediate and the diastereoselectivity arises from the electrophilic attack of electrophiles to the less hindered side of the enolates.
Phosphorus (P) is an essential nutrient element that is necessary for plant growth and development. However, most of the P exists in insoluble form. Aspergillus aculeatus has been reported to be able ...to solubilize insoluble forms of P. Here, to investigate the P-solubilizing effect of A. aculeatus on the performance of perennial ryegrass ( Lolium perenne ) under P-deficiency stress, we created four treatment groups: control i.e., no Ca 3 (PO 4 ) 2 or A. aculeatus , A. aculeatus only (F), Ca 3 (PO 4 ) 2 and Ca 3 (PO 4 ) 2 + A. aculeatus Ca 3 (PO 4 ) 2 + F treatment, and Ca 3 (PO 4 ) 2 at concentrations of 0 and 3 g per pot (0.5 kg substrate per pot). In our results, the liquid medium inoculated with A. aculeatus exhibited enhanced soluble P and organic acid content (tartaric acid, citric acid, and aminoacetic acid) accompanied with lower pH, compared with the noninoculated regimen. Furthermore, A. aculeatus also played a primary role in increasing the soluble P content of substrate (1 sawdust: 3 sand), the growth rate, turf quality, and photosynthetic capacity of the plant exposed to Ca 3 (PO 4 ) 2 + F treatment, compared with other groups. Finally, in perennial ryegrass leaves, there was a dramatic increase in the valine, serine, tyrosine, and proline contents, and a remarkable decline in the glutamic acid, succinic acid, citric acid, and fumaric acid contents in the Ca 3 (PO 4 ) 2 + F regimen, compared with other groups. Overall, our results suggested that A. aculeatus may play a crucial role in the process of solubilizing Ca 3 (PO 4 ) 2 and modulating perennial ryegrass growth under P-deficiency stress.
Cu(
i
)-Catalyzed diastereoselective carboboration of α-alkyl-substituted α,β-unsaturated carboxylic esters to produce β-boryl-α-quaternary carbon esters was developed. The carbon skeletons of ...dialkyl sulfates, primary allyl halides, and benzyl bromides were transferred to the α-position of the substrates to provide products in moderate to good yields with a diastereoselectivity of >95% in most cases. Substrates bearing a β-(hetero)aryl substituent gave higher diastereoselectivities than those bearing a linear β-alkyl substituent. The crystal structure of the potassium trifluoroborate derivative shows that the reactions probably go through a copper(
i
) enolate intermediate and the diastereoselectivity arises from the electrophilic attack of electrophiles to the less hindered side of the enolates.
Cu(
i
)-Catalyzed diastereoselective carboboration of α-alkyl-substituted α,β-unsaturated carboxylic esters to produce β-boryl-α-quaternary carbon esters was developed.
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