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BMC Plant Biology Jun 2024The Prunus sibirica seeds with rich oils has great utilization, but contain amygdalin that can be hydrolyzed to release toxic HCN. Thus, how to effectively reduce seed...
BACKGROUND
The Prunus sibirica seeds with rich oils has great utilization, but contain amygdalin that can be hydrolyzed to release toxic HCN. Thus, how to effectively reduce seed amygdalin content of P. sibirica is an interesting question. Mandelonitrile is known as one key intermediate of amygdalin metabolism, but which mandelonitrile lyase (MDL) family member essential for its dissociation destined to low amygdalin accumulation in P. sibirica seeds still remains enigmatic. An integration of our recent 454 RNA-seq data, amygdalin and mandelonitrile content detection, qRT-PCR analysis and function determination is described as a critical attempt to determine key MDL and to highlight its function in governing mandelonitrile catabolism with low amygdalin accumulation in Prunus sibirica seeds for better developing edible oil and biodiesel in China.
RESULTS
To identify key MDL and to unravel its function in governing seed mandelonitrile catabolism with low amygdalin accumulation in P. sibirica. Global identification of mandelonitrile catabolism-associated MDLs, integrated with the across-accessions/developing stages association of accumulative amount of amygdalin and mandelonitrile with transcriptional level of MDLs was performed on P. sibirica seeds of 5 accessions to determine crucial MDL2 for seed mandelonitrile catabolism of P. sibirica. MDL2 gene was cloned from the seeds of P. sibirica, and yeast eukaryotic expression revealed an ability of MDL2 to specifically catalyze the dissociation of mandelonitrile with the ideal values of K (0.22 mM) and V (178.57 U/mg). A combination of overexpression and mutation was conducted in Arabidopsis. Overexpression of PsMDL2 decreased seed mandelonitrile content with an increase of oil accumulation, upregulated transcript of mandelonitrile metabolic enzymes and oil synthesis enzymes (involving FA biosynthesis and TAG assembly), but exhibited an opposite situation in mdl2 mutant, revealing a role of PsMDL2-mediated regulation in seed amygdalin and oil biosynthesis. The PsMDL2 gene has shown as key molecular target for bioengineering high seed oil production with low amygdalin in oilseed plants.
CONCLUSIONS
This work presents the first integrated assay of genome-wide identification of mandelonitrile catabolism-related MDLs and the comparative association of transcriptional level of MDLs with accumulative amount of amygdalin and mandelonitrile in the seeds across different germplasms and developmental periods of P. sibirica to determine MDL2 for mandelonitrile dissociation, and an effective combination of PsMDL2 expression and mutation, oil and mandelonitrile content detection and qRT-PCR assay was performed to unravel a mechanism of PsMDL2 for controlling amygdalin and oil production in P. sibirica seeds. These findings could offer new bioengineering strategy for high oil production with low amygdalin in oil plants.
Topics: Amygdalin; Prunus; Seeds; Plant Proteins; Plant Oils; Aldehyde-Lyases; Gene Expression Regulation, Plant
PubMed: 38902595
DOI: 10.1186/s12870-024-05300-4 -
Nutrients May 2024Sphingosine-1-phosphate lyase (SPL) resides at the endpoint of the sphingolipid metabolic pathway, catalyzing the irreversible breakdown of sphingosine-1-phosphate....
-Acetylcysteine Alleviates Impaired Muscular Function Resulting from Sphingosine Phosphate Lyase Functional Deficiency-Induced Sphingoid Base and Ceramide Accumulation in .
Sphingosine-1-phosphate lyase (SPL) resides at the endpoint of the sphingolipid metabolic pathway, catalyzing the irreversible breakdown of sphingosine-1-phosphate. Depletion of SPL precipitates compromised muscle morphology and function; nevertheless, the precise mechanistic underpinnings remain elusive. Here, we elucidate a model of SPL functional deficiency in using RNA interference. Within these SPL-deficient nematodes, we observed diminished motility and perturbed muscle fiber organization, correlated with the accumulation of sphingoid bases, their phosphorylated forms, and ceramides (collectively referred to as the "sphingolipid rheostat"). The disturbance in mitochondrial morphology was also notable, as SPL functional loss resulted in heightened levels of reactive oxygen species. Remarkably, the administration of the antioxidant -acetylcysteine (NAC) ameliorates locomotor impairment and rectifies muscle fiber disarray, underscoring its therapeutic promise for ceramide-accumulation-related muscle disorders. Our findings emphasize the pivotal role of SPL in preserving muscle integrity and advocate for exploring antioxidant interventions, such as NAC supplementation, as prospective therapeutic strategies for addressing muscle function decline associated with sphingolipid/ceramide metabolism disruption.
Topics: Animals; Caenorhabditis elegans; Acetylcysteine; Ceramides; Aldehyde-Lyases; Sphingolipids; Reactive Oxygen Species; Antioxidants; Muscles; RNA Interference; Sphingosine
PubMed: 38892556
DOI: 10.3390/nu16111623 -
Stem Cell Research Aug 2024Hereditary fructose intolerance (HFI) is an autosomal recessive metabolic disease associated with a mutation in the aldolase B gene on chromosome 9q31. In this study, we...
Hereditary fructose intolerance (HFI) is an autosomal recessive metabolic disease associated with a mutation in the aldolase B gene on chromosome 9q31. In this study, we generated a human-induced pluripotent stem cell (hiPSC) line, FDCHi015-A, from peripheral blood mononuclear cells (PBMCs) of a patient carrying the compound heterozygous mutations c.360_364delCAAA and c.1013C > T in exons 4 and 9 of the ALDOB gene, respectively. The iPSCs with the confirmed patient-specific mutation demonstrate pluripotency markers expression, a normal karyotype, and the ability to differentiate into derivatives of three germ layers.
Topics: Humans; Induced Pluripotent Stem Cells; Leukocytes, Mononuclear; Mutation; Fructose-Bisphosphate Aldolase; Cell Line; Cell Differentiation; Male; Karyotype
PubMed: 38820866
DOI: 10.1016/j.scr.2024.103451 -
Nature Communications Apr 2024The increasing availability of experimental and computational protein structures entices their use for function prediction. Here we develop an automated procedure to...
The increasing availability of experimental and computational protein structures entices their use for function prediction. Here we develop an automated procedure to identify enzymes involved in metabolic reactions by assessing substrate conformations docked to a library of protein structures. By screening AlphaFold-modeled vitamin B6-dependent enzymes, we find that a metric based on catalytically favorable conformations at the enzyme active site performs best (AUROC Score=0.84) in identifying genes associated with known reactions. Applying this procedure, we identify the mammalian gene encoding hydroxytrimethyllysine aldolase (HTMLA), the second enzyme of carnitine biosynthesis. Upon experimental validation, we find that the top-ranked candidates, serine hydroxymethyl transferase (SHMT) 1 and 2, catalyze the HTMLA reaction. However, a mouse protein absent in humans (threonine aldolase; Tha1) catalyzes the reaction more efficiently. Tha1 did not rank highest based on the AlphaFold model, but its rank improved to second place using the experimental crystal structure we determined at 2.26 Å resolution. Our findings suggest that humans have lost a gene involved in carnitine biosynthesis, with HTMLA activity of SHMT partially compensating for its function.
Topics: Humans; Animals; Mice; Fructose-Bisphosphate Aldolase; Aldehyde-Lyases; Catalysis; Gene Library; Glycine Hydroxymethyltransferase; Carnitine; Mammals
PubMed: 38615009
DOI: 10.1038/s41467-024-47466-3 -
International Journal of Molecular... Mar 2024Rubisco large-subunit methyltransferase (LSMT), a SET-domain protein lysine methyltransferase, catalyzes the formation of trimethyl-lysine in the large subunit of...
Rubisco large-subunit methyltransferase (LSMT), a SET-domain protein lysine methyltransferase, catalyzes the formation of trimethyl-lysine in the large subunit of Rubisco or in fructose-1,6-bisphosphate aldolases (FBAs). Rubisco and FBAs are both vital proteins involved in CO fixation in chloroplasts; however, the physiological effect of their trimethylation remains unknown. In , a homolog of LSMT (NoLSMT) is found. Phylogenetic analysis indicates that NoLSMT and other algae LSMTs are clustered in a basal position, suggesting that algal species are the origin of LSMT. As NoLSMT lacks the His-Ala/ProTrp triad, it is predicted to have FBAs as its substrate instead of Rubisco. The 18-20% reduced abundance of FBA methylation in NoLSMT-defective mutants further confirms this observation. Moreover, this gene () can be induced by low-CO conditions. Intriguingly, NoLSMT-knockout mutants exhibit a 9.7-13.8% increase in dry weight and enhanced growth, which is attributed to the alleviation of photoinhibition under high-light stress. This suggests that the elimination of FBA trimethylation facilitates carbon fixation under high-light stress conditions. These findings have implications in engineering carbon fixation to improve microalgae biomass production.
Topics: Aldehyde-Lyases; Lysine; Ribulose-Bisphosphate Carboxylase; Biomass; Carbon Dioxide; Phylogeny; Fructose-Bisphosphate Aldolase; Histone-Lysine N-Methyltransferase; Chloroplasts
PubMed: 38612566
DOI: 10.3390/ijms25073756 -
Biomedicine & Pharmacotherapy =... May 2024Sepsis is characterized as life-threatening organ dysfunction caused by a dysregulated host response to an infection. Despite numerous clinical trials that addressed...
Sepsis is characterized as life-threatening organ dysfunction caused by a dysregulated host response to an infection. Despite numerous clinical trials that addressed this syndrome, there is still no causative treatment available to dampen its severity. Curtailing the infection at an early stage with anti-infectives is the only effective treatment regime besides intensive care. In search for additional treatment options, we recently discovered the inhibition of the sphingosine 1-phosphate (S1P) lyase and subsequent activation of the S1P receptor type 3 (S1PR3) in pre-conditioning experiments as promising targets for sepsis prevention. Here, we demonstrate that treatment of septic mice with the direct S1P lyase inhibitor C31 or the S1PR3 agonist CYM5541 in the advanced phase of sepsis resulted in a significantly increased survival rate. A single dose of each compound led to a rapid decline of sepsis severity in treated mice and coincided with decreased cytokine release and increased lung barrier function with unaltered bacterial load. The survival benefit of both compounds was completely lost in S1PR3 deficient mice. Treatment of the murine macrophage cell line J774.1 with either C31 or CYM5541 resulted in decreased protein kinase B (Akt) and stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK) phosphorylation without alteration of the mitogen-activated protein kinase (MAPK) p38 and p44/42 phosphorylation. Thus, activation of S1PR3 in the acute phase of sepsis by direct agonism or S1P lyase inhibition dampened Akt and JNK phosphorylation, resulting in decreased cytokine release, improved lung barrier stability, rapid decline of sepsis severity and better survival in mice.
Topics: Animals; Sepsis; Sphingosine-1-Phosphate Receptors; Aldehyde-Lyases; Mice, Inbred C57BL; Mice; Receptors, Lysosphingolipid; Male; Disease Models, Animal; Cell Line; Proto-Oncogene Proteins c-akt; Cytokines; Mice, Knockout
PubMed: 38599060
DOI: 10.1016/j.biopha.2024.116575 -
Scientific Reports Mar 2024Colorectal cancer (CRC) is one of the most common malignant tumors of the digestive tract and a leading cause of cancer-related death worldwide. Since many CRC patients...
Colorectal cancer (CRC) is one of the most common malignant tumors of the digestive tract and a leading cause of cancer-related death worldwide. Since many CRC patients are diagnosed already in the advanced stage, and traditional chemoradiotherapy is prone to drug resistance, it is important to find new therapeutic targets. In this study, the expression levels of ALDOA and p-AKT were detected in cancer tissues and paired normal tissues, and it was found that they were significantly increased in CRC tissues, and their high expression indicated poor prognosis. Moreover, a positive correlation between the expression of ALDOA and p-AKT was found in CRC tissues and paired normal tissues. In addition, the Kaplan-Meier analysis revealed that the group with both negative of ALDOA/p-AKT expression had longer five-year survival rates compared with the other group. Besides, the group with both high expression of ALDOA/p-AKT had a worse prognosis compared with the other group. Based on the expression of ALDOA and p-AKT in tumor tissues, we can effectively distinguish tumor tissues from normal tissues through cluster analysis. Furthermore, we constructed nomograms to predict 3-year and 5-year overall survival, showing that the expression of ALDOA/p-AKT plays a crucial role in predicting the prognosis of CRC patients. Therefore, ALDOA/p-AKT may act as a crucial role in CRC, which may provide new horizons for targeted therapies for CRC.
Topics: Humans; Proto-Oncogene Proteins c-akt; Prognosis; Kaplan-Meier Estimate; Colorectal Neoplasms; Fructose-Bisphosphate Aldolase
PubMed: 38499636
DOI: 10.1038/s41598-024-57209-5 -
The Journal of Biological Chemistry Apr 2024Zinc is required for many critical processes, including intermediary metabolism. In Saccharomyces cerevisiae, the Zap1 activator regulates the transcription of ∼80...
Zinc is required for many critical processes, including intermediary metabolism. In Saccharomyces cerevisiae, the Zap1 activator regulates the transcription of ∼80 genes in response to Zn supply. Some Zap1-regulated genes are Zn transporters that maintain Zn homeostasis, while others mediate adaptive responses that enhance fitness. One adaptive response gene encodes the 2-cysteine peroxiredoxin Tsa1, which is critical to Zn-deficient (ZnD) growth. Depending on its redox state, Tsa1 can function as a peroxidase, a protein chaperone, or a regulatory redox sensor. In a screen for possible Tsa1 regulatory targets, we identified a mutation (cdc19) that partially suppressed the tsa1Δ growth defect. The cdc19 mutation reduced activity of its protein product, pyruvate kinase isozyme 1 (Pyk1), implicating Tsa1 in adapting glycolysis to ZnD conditions. Glycolysis requires activity of the Zn-dependent enzyme fructose-bisphosphate aldolase 1, which was substantially decreased in ZnD cells. We hypothesized that in ZnD tsa1Δ cells, the loss of a compensatory Tsa1 regulatory function causes depletion of glycolytic intermediates and restricts dependent amino acid synthesis pathways, and that the decreased activity of Pyk1 counteracted this depletion by slowing the irreversible conversion of phosphoenolpyruvate to pyruvate. In support of this model, supplementing ZnD tsa1Δ cells with aromatic amino acids improved their growth. Phosphoenolpyruvate supplementation, in contrast, had a much greater effect on growth rate of WT and tsa1Δ ZnD cells, indicating that inefficient glycolysis is a major factor limiting yeast growth. Surprisingly however, this restriction was not primarily due to low fructose-bisphosphate aldolase 1 activity, but instead occurs earlier in glycolysis.
Topics: Saccharomyces cerevisiae; Glycolysis; Saccharomyces cerevisiae Proteins; Zinc; Fructose-Bisphosphate Aldolase; Peroxiredoxins; Pyruvate Kinase; Gene Expression Regulation, Fungal; Peroxidases; Mutation; Transcription Factors
PubMed: 38460940
DOI: 10.1016/j.jbc.2024.107147 -
Functional & Integrative Genomics Mar 2024Hepatocellular carcinoma (HCC) is one of the malignancies with the worst prognosis worldwide, in the occurrence and development of which glycolysis plays a central role....
Hepatocellular carcinoma (HCC) is one of the malignancies with the worst prognosis worldwide, in the occurrence and development of which glycolysis plays a central role. This study uncovered a mechanism by which ZNF692 regulates ALDOA-dependent glycolysis in HCC cells. RT-qPCR and western blotting were used to detect the expression of ZNF692, KAT5, and ALDOA in HCC cell lines and a normal liver cell line. The influences of transfection-induced alterations in the expression of ZNF692, KAT5, and ALDOA on the functions of HepG2 cells were detected by performing MTT, flow cytometry, Transwell, cell scratch, and colony formation assays, and the levels of glucose and lactate were determined using assay kits. ChIP and luciferase reporter assays were conducted to validate the binding of ZNF692 to the KAT5 promoter, and co-IP assays to detect the interaction between KAT5 and ALDOA and the acetylation of ALDOA. ZNF692, KAT5, and ALDOA were highly expressed in human HCC samples and cell lines, and their expression levels were positively correlated in HCC. ZNF692, ALDOA, or KAT5 knockdown inhibited glycolysis, proliferation, invasion, and migration and promoted apoptosis in HepG2 cells. ZNF692 bound to the KAT5 promoter and promoted its activity. ALDOA acetylation levels were elevated in HCC cell lines. KAT5 bound to ALDOA and catalyzed ALDOA acetylation. ALDOA or KAT5 overexpression in the same time of ZNF692 knockdown, compared to ZNF692 knockdown only, stimulated glycolysis, proliferation, invasion, and migration and reduced apoptosis in HepG2 cells. ZNF692 promotes the acetylation modification and protein expression of ALDOA by catalyzing KAT5 transcription, thereby accelerating glycolysis to drive HCC cell development.
Topics: Humans; Carcinoma, Hepatocellular; Liver Neoplasms; Cell Line, Tumor; Hep G2 Cells; Glycolysis; Cell Proliferation; Gene Expression Regulation, Neoplastic; Fructose-Bisphosphate Aldolase
PubMed: 38453820
DOI: 10.1007/s10142-024-01326-x -
Journal of Lipid Research Mar 2024The availability of genome-wide transcriptomic and proteomic datasets is ever-increasing and often not used beyond initial publication. Here, we applied module-based...
The availability of genome-wide transcriptomic and proteomic datasets is ever-increasing and often not used beyond initial publication. Here, we applied module-based coexpression network analysis to a comprehensive catalog of 35 mouse genome-wide liver expression datasets (encompassing more than 3800 mice) with the goal of identifying and validating unknown genes involved in cholesterol metabolism. From these 35 datasets, we identified a conserved module of genes enriched with cholesterol biosynthetic genes. Using a systematic approach across the 35 datasets, we identified three genes (Rdh11, Echdc1, and Aldoc) with no known role in cholesterol metabolism. We then performed functional validation studies and show that each gene is capable of regulating cholesterol metabolism. For the glycolytic gene, Aldoc, we demonstrate that it contributes to de novo cholesterol biosynthesis and regulates cholesterol and triglyceride levels in mice. As Aldoc is located within a genome-wide significant genome-wide association studies locus for human plasma cholesterol levels, our studies establish Aldoc as a causal gene within this locus. Through our work, we develop a framework for leveraging mouse genome-wide liver datasets for identifying and validating genes involved in cholesterol metabolism.
Topics: Humans; Mice; Animals; Fructose-Bisphosphate Aldolase; Genome-Wide Association Study; Proteomics; Cholesterol; Liver
PubMed: 38417553
DOI: 10.1016/j.jlr.2024.100525