Increased ratio of mitochondrial rDNA to cytoplasmic rDNA during zoosporic and germinating cyst stages of the life cycle of Phytophthora infestans (Mont.) de Bary

2002 ◽  
Vol 48 (3) ◽  
pp. 268-274 ◽  
Author(s):  
Ramiro París ◽  
Lorenzo Lamattina
Keyword(s):  
Phytophthora Infestans ◽  
Large Subunit ◽  
Mitochondrial Protein ◽  
Mitochondrial Activity ◽  
Rdna Transcription ◽  
Dot Blot ◽  
Mitochondrial Rrna ◽  
High Level ◽  
Differential Rna Display ◽  
Mitochondrial Rdna

A differential RNA display approach was used to study the gene expression in zoospores (Z) and germinating cysts (GC) of the late blight pathogen Phytophthora infestans. Four differentially amplified cDNAs were selected and cloned. The clone pGPiZ0.5 showed a 2.7-kb transcript highly expressed in Z. A BLAST search revealed an almost full sequence homology (98%) to the P. infestans mitochondrial large subunit rRNA. Northern blot analysis showed a twofold accumulation of the mitochondrial rRNA (mit rRNA) in Z compared with that of GC and mycelia of P. infestans. The high level of mit rRNA in Z might reflect an increased number of gene copies, an increased rDNA transcription rate, or both. Dot blot experiments indicated that the amount of mitochondrial rDNA (mit rDNA) relative to cytoplasmic rDNA is twofold higher in Z and GC than in mycelia. This relatively elevated mit rDNA could explain the high level of mit rRNA in the zoosporic phase. On the contrary, GC conserves the mit rDNA content, but the level of mit rRNA drops to 50% that of Z. The data are consistent with a very active mitochondrial protein synthesis during zoosporic phase, followed by a rapid down-regulation of mitochondrial activity during cyst formation.Key words: cytoplasmic rRNA, differential RNA display, mitochondrial rRNA, Phytophthora infestans, rDNA.

Deregulation of c-myc gene expression in human colon carcinoma is not accompanied by amplification or rearrangement of the gene

1985 ◽  
Vol 5 (8) ◽  
pp. 1969-1976
Author(s):  
M D Erisman ◽  
P G Rothberg ◽  
R E Diehl ◽  
C C Morse ◽  
J M Spandorfer ◽  
...  
Keyword(s):  
Colon Carcinoma ◽  
Cell Lines ◽  
Blot Hybridization ◽  
Human Colon ◽  
Normal Colonic Mucosa ◽  
Dna Rearrangement ◽  
Dot Blot ◽  
Myc Oncogene ◽  
Elevated Expression ◽  
High Level

The structure and expression of the c-myc oncogene were examined in 29 primary human colon adenocarcinomas. Dot blot hybridization of total RNA showed that 21 tumors (72%) had considerably elevated expression of c-myc (5- to 40-fold) relative to normal colonic mucosa. These data were corroborated by Northern blots of polyadenylated RNA, which showed a 2.3-kilobase transcript. Southern analysis of the c-myc locus in these tumors indicated the absence of amplification or DNA rearrangement in a 35-kilobase region encompassing the gene. In a parallel study, elevated expression of c-myc without amplification or DNA rearrangement was also observed in three of six colon carcinoma cell lines examined; in addition, unlike a normal colon cell line control, these three cell lines exhibited constitutive, high-level expression of the gene during their growth in cultures. These results indicate that elevated expression of the c-myc oncogene occurs frequently in primary human colon carcinomas and that the mechanism involved in the regulation of c-myc expression is altered in tumor-derived cell lines.

scholarly journals Downregulation of DJ-1 Fails to Protect Mitochondrial Complex I Subunit NDUFS3 in the Testes and Contributes to the Asthenozoospermia

2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Yupeng Wang ◽  
Yi Sun ◽  
Xin Zhao ◽  
Renpei Yuan ◽  
Hui Jiang ◽  
...  
Keyword(s):  
Male Infertility ◽  
Complex I ◽  
Mitochondrial Protein ◽  
Protein Product ◽  
Mitochondrial Activity ◽  
Mitochondrial Complex ◽  
Specific Mechanism ◽  
Nicotinamide Adenine Dinucleotide Dehydrogenase ◽  
Complex I Activity ◽  
Mitochondria Complex I

Asthenozoospermia (AS), an important cause of male infertility, is characterized by reduced sperm motility. Among the aetiologies of AS, inflammation seems to be the main cause. DJ-1, a conserved protein product of thePARK7gene, is associated with male infertility and plays a role in oxidative stress and inflammation. Although our previous studies showed that a reduction in DJ-1 was accompanied by mitochondrial dysfunction in the sperm of patients with AS, the specific mechanism underlying this association remained unclear. In this study, we found that compared to the patients without AS, the expression of mitochondrial protein nicotinamide adenine dinucleotide dehydrogenase (ubiquinone) Fe-S protein 3 (NDUFS3) was also significantly decreased in the sperm of patients with AS. Similarly, decreased expression of DJ-1 and NDUFS3 and reduced mitochondria complex I activity were evident in a rat model of AS. Moreover, we showed that the interaction between DJ-1 and NDUFS3 in rat testes was weakened by ORN treatment. These results suggest that the impaired mitochondrial activity could be due to the broken interaction between DJ-1 and NDUFS3 and that downregulation of DJ-1 in sperm and testes contributes to AS pathogenesis.

scholarly journals Nonradioactive in situ hybridization for detection of mRNAs encoding for peroxisomal proteins: heterogeneous hepatic lobular distribution after treatment with a single dose of bezafibrate.

1996 ◽  
Vol 44 (8) ◽  
pp. 825-834 ◽  
Author(s):  
A Schad ◽  
H D Fahimi ◽  
A Völkl ◽  
E Baumgart
Keyword(s):  
Single Dose ◽  
High Sensitivity ◽  
Fold Increase ◽  
Urate Oxidase ◽  
Dot Blot ◽  
Liver Lobule ◽  
Perfusion Fixation ◽  
High Level ◽  
Parenchymal Cells ◽  
Dot Blot Analysis

We present a nonradioactive in siru hybridization (ISH) protocol for detection of mRNAs in rat liver encoding for three peroxisomal proteins: catalase and urate oxidase as representatives of high-level abundance mRNAs and trifunctional protein (PH) as that of low-level abundance mRNAs. In addition to normal rats, animals treated for 24 hr with a single dose of bezafibrate were studied. The use of perfusion-fixation with 4% depolymerized paraformaldehyde/0.05% glutaraldehyde combined with paraffin embedding and the application of digoxigenin-labeled cRNA probes provided optimal cytological resolution and high sensitivity comparable to that of radioactive ISH. In parallel experiments, the same digoxigenin-labeled cRNA probes were used for Northern and semiquantitative dot-blot analysis of isolated RNAs. In control animals, the mRNAs for catalase and urate oxidase were uniformly distributed across the liver lobule and were confined to liver parenchymal cells. The bile duct epithelial and the sinusoidal cells remained negative. The specificity and the high resolution of our protocol were further substantiated by reciprocal localization of transcripts for albumin and glyceraldehyde-3-phosphate dehydrogenase in different regions of the liver lobule and for catalase in the proximal tubules of the renal cortex. Whereas in control livers the transcripts for PH were barely detectable, a strong signal was found in pericentral hepatocytes of bezafibratetreated animals, corresponding to an 8-10-fold increase of mRNA detected in dot-blots. In contrast, the urate oxidase mRNA was reduced by more than 50%, with diminution of staining in pericentral regions of the liver lobule. The mRNA encoding for catalase was only slightly affected. Further applications of this protocol should be helpful in elucidation of the cell-specific transcriptional regulation of peroxisomal proteins in various organs under normal and pathological conditions.

scholarly journals Thyroid Hormone Stimulation of Autophagy Is Essential for Mitochondrial Biogenesis and Activity in Skeletal Muscle

Endocrinology ◽  
2016 ◽  
Vol 157 (1) ◽  
pp. 23-38 ◽  
Author(s):  
Ronny Lesmana ◽  
Rohit A. Sinha ◽  
Brijesh K. Singh ◽  
Jin Zhou ◽  
Kenji Ohba ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Thyroid Hormone ◽  
Protein Kinase ◽  
Mitochondrial Biogenesis ◽  
Mitochondrial Protein ◽  
Adenosine Monophosphate ◽  
Mitochondrial Activity ◽  
Dependent Manner ◽  
In Vivo Models ◽  
Stimulation Of

Abstract Thyroid hormone (TH) and autophagy share similar functions in regulating skeletal muscle growth, regeneration, and differentiation. Although TH recently has been shown to increase autophagy in liver, the regulation and role of autophagy by this hormone in skeletal muscle is not known. Here, using both in vitro and in vivo models, we demonstrated that TH induces autophagy in a dose- and time-dependent manner in skeletal muscle. TH induction of autophagy involved reactive oxygen species (ROS) stimulation of 5′adenosine monophosphate-activated protein kinase (AMPK)-Mammalian target of rapamycin (mTOR)- Unc-51-like kinase 1 (Ulk1) signaling. TH also increased mRNA and protein expression of key autophagy genes, microtubule-associated protein light chain 3 (LC3), Sequestosome 1 (p62), and Ulk1, as well as genes that modulated autophagy and Forkhead box O (FOXO) 1/3a. TH increased mitochondrial protein synthesis and number as well as basal mitochondrial O2 consumption, ATP turnover, and maximal respiratory capacity. Surprisingly, mitochondrial activity and biogenesis were blunted when autophagy was blocked in muscle cells by Autophagy-related gene (Atg)5 short hairpin RNA (shRNA). Induction of ROS and 5′adenosine monophosphate-activated protein kinase (AMPK) by TH played a significant role in the up-regulation of Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PPARGC1A), the key regulator of mitochondrial synthesis. In summary, our findings showed that TH-mediated autophagy was essential for stimulation of mitochondrial biogenesis and activity in skeletal muscle. Moreover, autophagy and mitochondrial biogenesis were coupled in skeletal muscle via TH induction of mitochondrial activity and ROS generation.

scholarly journals Interleukin 21 Receptor Affects Adipogenesis of Human Adipose-Derived Stem/Stromal Cells

2022 ◽  
Vol 2022 ◽  
pp. 1-14
Author(s):  
Bruna Cristina Falavinha ◽  
María Julia Barisón ◽  
Carmen Lúcia Kuniyoshi Rebelatto ◽  
Bruna Hilzendeger Marcon ◽  
Alessandra de Melo Aguiar ◽  
...  
Keyword(s):  
Stromal Cells ◽  
Metabolic Diseases ◽  
Adipogenic Differentiation ◽  
Mrna Level ◽  
Mitochondrial Protein ◽  
Mitochondrial Activity ◽  
Confocal Immunofluorescence ◽  
Human Adscs ◽  
Interleukin 21 ◽  
Adipose Tissue Cells

Dysfunctions in adipose tissue cells are responsible for several obesity-related metabolic diseases. Understanding the process of adipocyte formation is thus fundamental for understanding these diseases. The adipocyte differentiation of adipose-derived stem/stromal cells (ADSCs) showed a reduction in the mRNA level of the interleukin 21 receptor (IL21R) during this process. Although the receptor has been associated with metabolic diseases, few studies have examined its function in stem cells. In this study, we used confocal immunofluorescence assays to determine that IL21R colocalizes with mitochondrial protein ATP5B, ALDH4A1, and the nucleus of human ADSCs. We demonstrated that silencing and overexpression of IL21R did not affect the cell proliferation and mitochondrial activity of ADSCs. However, IL21R silencing did reduce ADSC adipogenic capacity. Further studies are needed to understand the mechanism involved between IL21R and the adipogenic differentiation process.

scholarly journals Isolation, characterization, and comparative genomic analysis of a phage infecting high-level aminoglycoside-resistant (HLAR) Enterococcus faecalis

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e9171 ◽  
Author(s):  
Danial Nasr Azadani ◽  
Daiyuan Zhang ◽  
J. Robert Hatherill ◽  
David Silva ◽  
Jeffrey W. Turner
Keyword(s):  
Genome Sequencing ◽  
Large Subunit ◽  
Gc Content ◽  
Genomic Analysis ◽  
Comparative Genomic Analysis ◽  
Single Locus ◽  
Comparative Genomic ◽  
Antibiotic Resistant ◽  
High Level ◽  
High Degree

Enterococcus is a genus of Gram-positive bacteria that are commensal to the gastrointestinal tracts of humans but some species have been increasingly implicated as agents of nosocomial infections. The increase in infections and the spread of antibiotic-resistant strains have contributed to renewed interest in the discovery of Enterococcus phages. The aims of this study were (1) the isolation, characterization, and genome sequencing of a phage capable of infecting an antibiotic-resistant E. faecalis strain, and (2) the comparative genomic analysis of publicly-available Enterococcus phages. For this purpose, multiple phages were isolated from wastewater treatment plant (WWTP) influent using a high-level aminoglycoside-resistant (HLAR) E. faecalis strain as the host. One phage, phiNASRA1, demonstrated a high lytic efficiency (∼97.52%). Transmission electron microscopy (TEM) and whole-genome sequencing (WGS) showed that phiNASRA1 belongs to the Siphoviridae family of double-stranded DNA viruses. The phage was approximately 250 nm in length and its complete genome (40,139 bp, 34.7% GC) contained 62 open reading frames (ORFs). Phylogenetic comparisons of phiNASRA1 and 31 publicly-available Enterococcus phages, based on the large subunit terminase and portal proteins, grouped phage by provenance, size, and GC content. In particular, both phylogenies grouped phages larger than 100 kbp into distinct clades. A phylogeny based on a pangenome analysis of the same 32 phages also grouped phages by provenance, size, and GC content although agreement between the two single-locus phylogenies was higher. Per the pangenome phylogeny, phiNASRA1 was most closely related to phage LY0322 that was similar in size, GC content, and number of ORFs (40,139 and 40,934 bp, 34.77 and 34.80%, and 60 and 64 ORFs, respectively). The pangenome analysis did illustrate the high degree of sequence diversity and genome plasticity as no coding sequence was homologous across all 32 phages, and even ‘conserved’ structural proteins (e.g., the large subunit terminase and portal proteins) were homologous in no more than half of the 32 phage genomes. These findings contribute to a growing body of literature devoted to understanding phage biology and diversity. We propose that this high degree of diversity limited the value of the single-locus and pangenome phylogenies. By contrast, the high degree of homology between phages larger than 100 kbp suggests that pangenome analyses of more similar phages is a viable method for assessing subclade diversity. Future work is focused on validating phiNASRA1 as a potential therapeutic agent to eradicate antibiotic-resistant E. faecalis infections in an animal model.

scholarly journals DeepPred-SubMito: A Novel Submitochondrial Localization Predictor Based on Multi-Channel Convolutional Neural Network and Dataset Balancing Treatment

2020 ◽  
Vol 21 (16) ◽  
pp. 5710
Author(s):  
Xiao Wang ◽  
Yinping Jin ◽  
Qiuwen Zhang
Keyword(s):  
Neural Network ◽  
Convolutional Neural Network ◽  
Cross Validation ◽  
Protein Localization ◽  
Mitochondrial Protein ◽  
Intermembrane Space ◽  
The Matrix ◽  
Localization Predictor ◽  
High Level ◽  
Fold Cross Validation

Mitochondrial proteins are physiologically active in different compartments, and their abnormal location will trigger the pathogenesis of human mitochondrial pathologies. Correctly identifying submitochondrial locations can provide information for disease pathogenesis and drug design. A mitochondrion has four submitochondrial compartments, the matrix, the outer membrane, the inner membrane, and the intermembrane space, but various existing studies ignored the intermembrane space. The majority of researchers used traditional machine learning methods for predicting mitochondrial protein localization. Those predictors required expert-level knowledge of biology to be encoded as features rather than allowing the underlying predictor to extract features through a data-driven procedure. Besides, few researchers have considered the imbalance in datasets. In this paper, we propose a novel end-to-end predictor employing deep neural networks, DeepPred-SubMito, for protein submitochondrial location prediction. First, we utilize random over-sampling to decrease the influence caused by unbalanced datasets. Next, we train a multi-channel bilayer convolutional neural network for multiple subsequences to learn high-level features. Third, the prediction result is outputted through the fully connected layer. The performance of the predictor is measured by 10-fold cross-validation and 5-fold cross-validation on the SM424-18 dataset and the SubMitoPred dataset, respectively. Experimental results show that the predictor outperforms state-of-the-art predictors. In addition, the prediction of results in the M983 dataset also confirmed its effectiveness in predicting submitochondrial locations.

scholarly journals An Autosomal Dominant Form of Ras-Related C3 Botulinum Toxin Substrate 2 (RAC2) Is Associated with Haematopoiesis Failure

Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 4306-4306
Author(s):  
Chantal Lagresle-Peyrou ◽  
Aurélien Olichon ◽  
Hanem Sadek ◽  
Philippe Roche ◽  
Claudine Tardy ◽  
...  
Keyword(s):  
Energy Demand ◽  
Clinical Phenotype ◽  
Severe Combined Immunodeficiency ◽  
Mitochondrial Protein ◽  
Small Gtpases ◽  
Small Gtpase ◽  
Mitochondrial Activity ◽  
Hematopoietic Stem ◽  
Screening Programs ◽  
The Impact

Abstract Severe combined immunodeficiencies (SCIDs) constitute a heterogeneous group of life-threatening genetic disorders that typically present in the first year of life. Reticular dysgenesis (RD) is an autosomal recessive form of human Severe Combined Immunodeficiency (SCIDs) characterized by the absence of blood neutrophils and T lymphocytes. This pathology is due to biallelic mutations in the adenylate kinase 2 (AK2) gene, encoding for a mitochondrial protein which regulates the homeostasis of adenine nucleotides. In three newborns presenting a RD-like clinical phenotype as frequent infections and a profound leukopenia, we identified an heterozygous dominant missense mutation in the gene coding for Rac Family Small GTPase 2 (RAC2) protein (p.G12R). Hematopoietic stem cell transplantation (HSCT) performed soon after birth was successful in two out of the three patients attesting that the inherited defect was intrinsic and not micro-environmental. RAC2 protein belongs to the Rac subfamily of RHO small GTPases. In the inactive GDP-bound state, RAC2 is located in the cytosol and upon stimulation, the active RAC2-GTP-bound form translocates to the plasma membrane. Unlike the other members of the Rac subfamily (RAC1 and RAC3), RAC2 is mostly expressed on hematopoietic cells and during T cell differentiation. To gain insight into the disease, we transduced human hematopoietic stem and progenitor cells (HSPCs) with a lentiviral construct containing the RAC2 mutated form. The mutation inhibits HSPCs proliferation and differentiation toward the myeloid and lymphoid lineages reproducing the patients' clinical phenotype. In this condition, we also observed high apoptosis level and an alteration of mitochondrial activity and Ros production. In a biochemical model, we demonstrated that the substitution of the glycine (G) amino-acid by a bulky flexible arginine (R) may prevent GTP hydrolysis. Lastly, our findings suggest that RAC2 gene sequencing must be considered in newborn screening programs for SCID detection. To decipher the mechanisms regulating RAC2 functions, we studied the impact of the p.G12R mutation on a human AML cell line expressing RAC2 protein. Our preliminary data highlight that the cell cycle and mitochondrial activity are disrupted by G12R mutation. By holotomography, we also observed morphological changes and accumulation of lipid droplets into the cells. All these data suggest that RAC2 defective signalling pathway is linked to cell metabolism imbalance and further investigations are ongoing to better understand how RAC2 controls cell energy demand, especially during differentiation. Disclosures Cavazzana: Smart Immune: Other: co-founder.

scholarly journals Complete mitochondrial genome of Muricea crassa and Muricea purpurea (Anthozoa: Octocorallia) from the eastern tropical Pacific

2016 ◽  
Author(s):  
Angelo Poliseno ◽  
Odalisca Breedy ◽  
Michael Eitel ◽  
Gert Wöerheide ◽  
Hector M. Guzman ◽  
...  
Keyword(s):  
Complete Mitochondrial Genome ◽  
Mitochondrial Protein ◽  
Gc Content ◽  
Tropical Pacific ◽  
Gene Arrangement ◽  
Eastern Tropical Pacific ◽  
Protein Coding ◽  
Protein Coding Genes ◽  
Intergenic Regions ◽  
High Level

AbstractWe sequenced the complete mitogenomes of two eastern tropical Pacific gorgonians, Muricea crassa and Muricea purpurea, using NGS technologies. The assembled mitogenomes of M. crassa and M. purpurea were 19,586 bp and 19,358 bp in length, with a GC-content ranging from 36.0% to 36.1%, respectively. The two mitogenomes had the same gene arrangement consisting of 14 protein-coding genes, two rRNAs and one tRNA. Mitogenome identity was 98.5%. The intergenic regions between COB and NAD6 and between NAD5 and NAD4 were polymorphic in length with a high level of nucleotide diversity. Based on a concatenated dataset of 14 mitochondrial protein-coding genes we inferred the phylogeny of 26 octocoral species.

Abstract 257: PP2Cm Regulation Links Branched Chain Amino Acid with Hypertrophy Response

2012 ◽  
Vol 111 (suppl_1) ◽  
Author(s):  
Meiyi Zhou ◽  
Zhihua Wang ◽  
Darwin Jeyaraj ◽  
Bangfen Pan ◽  
Ying Huang ◽  
...  
Keyword(s):  
Mrna Level ◽  
Mitochondrial Protein ◽  
Pressure Overload ◽  
Hypertrophic Response ◽  
Branched Chain Amino Acid ◽  
Rate Limiting Step ◽  
Branched Chain ◽  
High Level ◽  
Mtor Activity

[Introduction] Branched Chain Amino Acids (BCAAs), including leucine, isoleucine, and valine, modulate mTOR activity that controls protein synthesis and cell growth. PP2Cm is a mitochondrial protein phosphatase that regulates the rate limiting step of BCAA degradation. Loss of PP2Cm leads to BCAA accumulation. [Hypothesis] PP2Cm downregulation by hypertrophic signal impairs BCAA catabolism and thus hypertrophy response in heart. [Methods and Results] High level of PP2Cm is expressed in heart through all development stages. PP2Cm expression was reduced in hypertrophic heart induced by pressure overload, corresponding with increase of BCAA level and mTOR activity. KLF15 and microRNA22 are both key regulators of hypertrophy. It has been shown that hypertrophy signal s upregulated microRNA22 while decreasing KLF15 expression. We found that KLF15 increased PP2Cm promoter activity and miRNA22 regulated PP2Cm mRNA level and protein expression via 3’UTR . Together, our data indicated that hypertrophy inducers down-regulates KLF15 while increasing miRNA22, resulting in decreased PP2Cm level and thus repressed BCAA catabolism, which in turn can impact on mTOR mediated signaling and activity. [Conclusions] Pathological stress may affect the expression of PP2Cm and influence the outcome of hypertrophic response, suggesting an important role of BCAA nutrient and PP2Cm expression in heart.

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