Expressional diversity of grapevine 3-Hydroxy-3-methylglutaryl-CoA reductase (VvHMGR) in different grapes genotypes

Abstract Background 3-Hydroxy-3-methylglutaryl-CoA reductase (HMGR) is a key enzyme in the mevalonate (MVA) pathway, which regulates the metabolism of terpenoids in the cytoplasm and determines the type and content of downstream terpenoid metabolites. Results Results showed that grapevine HMGR family has three members, such as VvHMGR1, VvHMGR2, and VvHMGR3. The expression of VvHMGRs in 'Kyoho' has tissue specificity, for example, VvHMGR1 keeps a higher expression, VvHMGR2 is the lowest, and VvHMGR3 gradually decreases as the fruit development. VvHMGR3 is closely related to CsHMGR1 and GmHMGR9 and has collinearity with CsHMGR2 and GmHMGR4. By the prediction of interaction protein, it can interact with HMG-CoA synthase, MVA kinase, FPP/GGPP synthase, diphosphate mevalonate decarboxylase, and participates in the synthesis and metabolism of terpenoids. VvHMGR3 have similar trends in expression with some of the genes of carotenoid biosynthesis and MEP pathways. VvHMGR3 responds to various environmental and phytohormone stimuli, especially salt stress and ultraviolet (UV) treatment. The expression level of VvHMGRs is diverse in grapes of different colors and aroma. VvHMGRs are significantly higher in yellow varieties than that in red varieties, whereas rose-scented varieties showed significantly higher expression than that of strawberry aroma. The expression level is highest in yellow rose-scented varieties, and the lowest in red strawberry scent varieties, especially ‘Summer Black’ and ‘Fujiminori’. Conclusion This study confirms the important role of VvHMGR3 in the process of grape fruit coloring and aroma formation, and provided a new idea to explain the loss of grape aroma and poor coloring during production. There may be an additive effect between color and aroma in the HMGR expression aspect.

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ANS-deficient Arabidopsis is sensitive to high light due to impaired anthocyanin photoprotection

Functional Plant Biology ◽

10.1071/fp19042 ◽

2019 ◽

Vol 46 (8) ◽

pp. 756 ◽

Cited By ~ 2

Author(s):

Xiao-Ting Zheng ◽

Yi-Lin Chen ◽

Xiao-Hong Zhang ◽

Min-Ling Cai ◽

Zheng-Chao Yu ◽

...

Keyword(s):

Antioxidant Capacity ◽

Light Attenuation ◽

High Light ◽

Expression Level ◽

Anthocyanin Content ◽

Key Enzyme ◽

Positive Correlations ◽

Physiological And Biochemical ◽

Gene Expression Levels

Light attenuation and antioxidation are the main mechanisms of photoprotection by anthocyanin under high light (HL) stress. Anthocyanin synthase (ANS) is the key enzyme in the downstream portion of anthocyanin synthetic pathways. To explore the role of ANS in photoprotection by anthocyanin under HL stress, homozygous ANS-deficient Arabidopsis mutants were screened from SALK_073183 and SALK_028793. Here, we obtained two deficient mutants, ans-1 and ans-2, which had ANS gene expression levels equal to 5.9 and 32.9% of that of Col respectively. By analysing their physiological and biochemical responses to HL stress, we found that there were positive correlations among ANS expression level, anthocyanin content and resistance to HL. The line with the lowest ANS expression level, ans-1, was also the most sensitive to HL, showing the lowest anthocyanin content, chlorophyll content, Fv/Fm ratio, and Rubisco content and the highest O2•− accumulation and membrane leakage rate, although it also had the highest antioxidant capacity. Experimental evidence suggests that ANS mainly regulated the light-attenuating function of anthocyanin in photoprotection under HL. Blocking excess light is an important function of anthocyanin that protects plants from HL stress, and a high antioxidant capacity cannot compensate for the absence of the light-shielding function of anthocyanin.

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Regulated degradation of HMG-CoA reductase, an integral membrane protein of the endoplasmic reticulum, in yeast.

The Journal of Cell Biology ◽

10.1083/jcb.125.2.299 ◽

1994 ◽

Vol 125 (2) ◽

pp. 299-312 ◽

Cited By ~ 139

Author(s):

R Y Hampton ◽

J Rine

Keyword(s):

Mevalonate Pathway ◽

Integral Membrane Protein ◽

Integral Membrane Proteins ◽

Hmg Coa Reductase ◽

Key Enzyme ◽

Farnesylated Protein ◽

The Stability ◽

Coa Reductase ◽

Pathway Flux

Numerous integral membrane proteins are degraded in the mammalian ER. HMG-CoA reductase (HMG-R), a key enzyme in the mevalonate pathway by which isoprenoids and sterols are synthesized, is one substrate of ER degradation. The degradation of HMG-R is modulated by feedback signals from the mevalonate pathway. We investigated the role of regulated degradation of the two isozymes of HMG-R, Hmg1p and Hmg2p, in the physiology of Saccharomyces cerevisiae. Hmg1p was quite stable, whereas Hmg2p was rapidly degraded. Degradation of Hmg2p proceeded independently of vacuolar proteases or secretory traffic, indicating that Hmg2p degradation occurred at the ER. Hmg2p stability was strongly affected by modulation of the mevalonate pathway through pharmacological or genetic means. Decreased mevalonate pathway flux resulted in decreased degradation of Hmg2p. One signal for degradation of Hmg2p was a nonsterol, mevalonate-derived molecule produced before the synthesis of squalene. Genetic evidence indicated that a farnesylated protein may also be necessary for Hmg2p degradation. Studies with reporter genes demonstrated that the stability of each isozyme was determined by its noncatalytic NH2-terminal domain. Our data show that ER protein degradation is widely conserved among eukaryotes, and that feedback control of HMG-R degradation is an ancient paradigm of regulation.

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Tryptophan-Niacin Metabolism in Rat with Puromycin Aminonucleoside-Induced Nephrosis

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831.76.1.28 ◽

2006 ◽

Vol 76 (1) ◽

pp. 28-33 ◽

Cited By ~ 7

Author(s):

Yukari Egashira ◽

Shin Nagaki ◽

Hiroo Sanada

Keyword(s):

Body Weight ◽

Urinary Excretion ◽

Enzyme Activities ◽

Treated Group ◽

Control Group ◽

Puromycin Aminonucleoside ◽

Low Level ◽

Key Enzyme

We investigated the change of tryptophan-niacin metabolism in rats with puromycin aminonucleoside PAN-induced nephrosis, the mechanisms responsible for their change of urinary excretion of nicotinamide and its metabolites, and the role of the kidney in tryptophan-niacin conversion. PAN-treated rats were intraperitoneally injected once with a 1.0% (w/v) solution of PAN at a dose of 100 mg/kg body weight. The collection of 24-hour urine was conducted 8 days after PAN injection. Daily urinary excretion of nicotinamide and its metabolites, liver and blood NAD, and key enzyme activities of tryptophan-niacin metabolism were determined. In PAN-treated rats, the sum of urinary excretion of nicotinamide and its metabolites was significantly lower compared with controls. The kidneyα-amino-β-carboxymuconate-ε-semialdehyde decarboxylase (ACMSD) activity in the PAN-treated group was significantly decreased by 50%, compared with the control group. Although kidney ACMSD activity was reduced, the conversion of tryptophan to niacin tended to be lower in the PAN-treated rats. A decrease in urinary excretion of niacin and the conversion of tryptophan to niacin in nephrotic rats may contribute to a low level of blood tryptophan. The role of kidney ACMSD activity may be minimal concerning tryptophan-niacin conversion under this experimental condition.

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Acid ceramidase, a double-edged sword in cancer aggression: A minireview

Current Cancer Drug Targets ◽

10.2174/1568009620666201223154621 ◽

2020 ◽

Vol 20 ◽

Author(s):

Helen Shiphrah Vethakanraj ◽

Niveditha Chandrasekaran ◽

Ashok Kumar Sekar

Keyword(s):

Cell Fate ◽

Cancer Progression ◽

Potential Role ◽

Tumour Progression ◽

Acid Ceramidase ◽

The Core ◽

The Past ◽

Sphingosine 1 Phosphate ◽

Key Enzyme

: Acid ceramidase (AC), the key enzyme of the ceramide metabolic pathway hydrolyzes pro-apoptotic ceramide to sphingosine, which by the action of sphingosine-1-kinase is metabolized to mitogenic sphingosine-1-phosphate. The intracellular level of AC determines ceramide/sphingosine-1-phosphate rheostat which in turn decides the cell fate. The upregulated AC expression during cancerous condition acts as a “double-edged sword” by converting pro-apoptotic ceramide to anti-apoptotic sphingosine-1-phosphate, wherein on one end, the level of ceramide is decreased and on the other end, the level of sphingosine-1-phosphate is increased, thus altogether aggravating the cancer progression. In addition, cancer cells with upregulated AC expression exhibited increased cell proliferation, metastasis, chemoresistance, radioresistance and numerous strategies were developed in the past to effectively target the enzyme. Gene silencing and pharmacological inhibition of AC sensitized the resistant cells to chemo/radiotherapy thereby promoting cell death. The core objective of this review is to explore AC mediated tumour progression and the potential role of AC inhibitors in various cancer cell lines/models.

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Effect of HMG-CoA Reductase Inhibition on Vascular Smooth Muscle Cells Extracellular Matrix Production: Role of RhoA

Current Vascular Pharmacology ◽

10.2174/1570161114666160229115553 ◽

2016 ◽

Vol 14 (4) ◽

pp. 345-352 ◽

Cited By ~ 4

Author(s):

Rogelio Palomino-Morales ◽

Sonia Perales ◽

Carolina Torres ◽

Ana Linares ◽

Maria J. Alejandre

Keyword(s):

Extracellular Matrix ◽

Smooth Muscle ◽

Vascular Smooth Muscle ◽

Smooth Muscle Cells ◽

Vascular Smooth Muscle Cells ◽

Muscle Cells ◽

Extracellular Matrix Production ◽

Matrix Production ◽

Coa Reductase

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The Natural Products as Hydroxymethylglutaryl-Coa Reductase Inhibitors

Letters in Drug Design & Discovery ◽

10.2174/1570180816666181112144353 ◽

2019 ◽

Vol 16 (10) ◽

pp. 1130-1137

Author(s):

Hayrettin Ozan Gulcan ◽

Serkan Yigitkan ◽

Ilkay Erdogan Orhan

Keyword(s):

Natural Products ◽

Cardiovascular System ◽

High Cholesterol ◽

Chemical Structures ◽

Reductase Inhibitors ◽

Key Enzyme ◽

Serious Disease ◽

Coa Reductase ◽

Hydroxymethylglutaryl Coa Reductase ◽

Alternative Drugs

High cholesterol and triglyceride levels are mainly related to further generation of lifethreating metabolism disorders including cardiovascular system diseases. Therefore, hypercholesterolemia (i.e., also referred to as hyperlipoproteinemia) is a serious disease state, which must be controlled. Currently, the treatment of hypercholesterolemia is mainly achieved through the employment of statins in the clinic, although there are alternative drugs (e.g., ezetimibe, cholestyramine). In fact, the original statins are natural products directly obtained from fungi-like molds and mushrooms and they are potent inhibitors of hydroxymethylglutaryl-CoA reductase, the key enzyme in the biosynthesis of cholesterol. This review focuses on the first identification of natural statins, their synthetic and semi-synthetic analogues, and the validation of hydroxymethylglutaryl-CoA reductase as a target in the treatment of hypercholesterolemia. Furthermore, other natural products that have been shown to possess the potential to inhibit hydroxymethylglutaryl-CoA reductase are also reviewed with respect to their chemical structures.

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MicroRNA-520c-3p Modulates Doxorubicin-Chemosensitivity in HepG2 Cells

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520620666200502004817 ◽

2020 ◽

Vol 21 (2) ◽

pp. 237-245 ◽

Cited By ~ 1

Author(s):

Mohamed A. Ragheb ◽

Marwa H. Soliman ◽

Emad M. Elzayat ◽

Mervat S. Mohamed ◽

Nada El-Ekiaby ◽

...

Keyword(s):

Hepg2 Cells ◽

Therapeutic Strategy ◽

Suppressive Effect ◽

Expression Level ◽

Tumor Suppressor Function ◽

Protein Expression Level ◽

Blot Technique ◽

Induction Of Apoptosis ◽

The Impact

Background: Doxorubicin (DOX) is the most common drugs used in cancer therapy, including Hepatocellular Carcinoma (HCC). Drug resistance, is one of chemotherapy’s significant problems. Emerging studies have shown that microRNAs (miRNAs) could participate in regulating this mechanism. Nevertheless, the impact of miRNAs on HCC chemoresistance is still enigmatic. Objective: Investigating the role of miR-520c-3p in enhancement of anti-tumor effect of DOX against HepG2 cells. Methods: Expression profile for liver related miRNAs (384 miRNAs) has been analyzed on HepG2 cells treated with DOX using qRT-PCR. miR-520c-3p, the most deregulated miRNA, was selected for combination treatment with DOX. Expression level for LEF1, CDK2, CDH1, VIM, Mcl-1 and TP53 was evaluated in miR-520c-3p transfected cells. Cell viability, colony formation, wound healing as well as apoptosis assays have been demonstrated. Furthermore, Mcl-1 protein level was measured using western blot technique. Results: The present data indicated that miR-520c-3p overexpression could render HepG2 cells chemo-sensitive to DOX through enhancing its suppressive effects on proliferation, migration, and induction of apoptosis. The suppressive effect of miR-520c-3p involved altering the expression levels of some key regulators of cell cycle, proliferation, migration and apoptosis including LEF1, CDK2, CDH1, VIM, Mcl-1 and TP53. Interestingly, Mcl-1 was found to be one of the potential targets of miR-520c-3p, and its protein expression level was down-regulated upon miR-520c-3p overexpression. Conclusion: Our data referred to the tumor suppressor function of miR-520c-3p that could modulate chemosensitivity of HepG2 cells toward DOX treatment, providing a promising therapeutic strategy in HCC.

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Statin-Induced Autoimmune Necrotizing Myopathy

Journal of Primary Care & Community Health ◽

10.1177/21501327211028714 ◽

2021 ◽

Vol 12 ◽

pp. 215013272110287

Author(s):

Sahani Jayatilaka ◽

Kunal Desai ◽

Swarup Rijal ◽

Debra Zimmerman

Keyword(s):

Renal Failure ◽

Statin Therapy ◽

Initial Presentation ◽

Autoimmune Reaction ◽

Necrotizing Myopathy ◽

Starting Dose ◽

Key Enzyme ◽

Risk Patients ◽

Autoimmune Myopathy ◽

Coa Reductase

Statin therapy is a widely prescribed medication class for hypercholesterolemia. In statin-induced autoimmune myopathy, genetically predisposed and at-risk patients can develop antibodies against hydroxy-3-methylglutaryl-CoA reductase (HMGCR), the key enzyme in the production of cholesterol. As a result, an autoimmune reaction causing weakness, myalgia, with possible severe rhabdomyolysis, renal failure, and myonecrosis also can occur. A 73-year-old female presented to clinic with myalgia and fatigue. She was on atorvastatin 20 mg/day for over 1 year, which she stopped 1 week prior to her initial presentation. Patient did experience rhabdomyolysis as well as a transaminitis. She underwent an autoimmune workup which was positive for HMG-CoA reductase antibodies. Patient was initially treated on a prednisone taper, starting dose 50 mg/day. Without remission of symptoms, methotrexate 15 mg/week was initiated.

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Controlled Transcription of Regulator Gene carS by Tet-on or by a Strong Promoter Confirms Its Role as a Repressor of Carotenoid Biosynthesis in Fusarium fujikuroi

Microorganisms ◽

10.3390/microorganisms9010071 ◽

2020 ◽

Vol 9 (1) ◽

pp. 71

Author(s):

Julia Marente ◽

Javier Avalos ◽

M. Carmen Limón

Keyword(s):

Wild Strain ◽

Ring Finger ◽

Carotenoid Biosynthesis ◽

Negative Regulator ◽

Fusarium Fujikuroi ◽

Structural Genes ◽

Gene Encoding ◽

In The Wild ◽

Set Up

Carotenoid biosynthesis is a frequent trait in fungi. In the ascomycete Fusarium fujikuroi, the synthesis of the carboxylic xanthophyll neurosporaxanthin (NX) is stimulated by light. However, the mutants of the carS gene, encoding a protein of the RING finger family, accumulate large NX amounts regardless of illumination, indicating the role of CarS as a negative regulator. To confirm CarS function, we used the Tet-on system to control carS expression in this fungus. The system was first set up with a reporter mluc gene, which showed a positive correlation between the inducer doxycycline and luminescence. Once the system was improved, the carS gene was expressed using Tet-on in the wild strain and in a carS mutant. In both cases, increased carS transcription provoked a downregulation of the structural genes of the pathway and albino phenotypes even under light. Similarly, when the carS gene was constitutively overexpressed under the control of a gpdA promoter, total downregulation of the NX pathway was observed. The results confirmed the role of CarS as a repressor of carotenogenesis in F. fujikuroi and revealed that its expression must be regulated in the wild strain to allow appropriate NX biosynthesis in response to illumination.

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