Transcriptome response to ODC downregulation and reduced polyamine titres in tobacco
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ABSTRACT:
ORGANISM(S): Nicotiana tabacum
PROVIDER: GSE75134 | GEO | 2016/08/01
SECONDARY ACCESSION(S): PRJNA302626
REPOSITORIES: GEO
Similar Datasets
Project description:Although a lot is known about polyamines (PAs) and their functions, scientists have not yet been able to completely understand and elucidate their mode of action and interactive molecular partners. An attempt has been made in this direction by RNAi-mediated down-regulation of a key biosynthetic gene in PA metabolic pathway, ornithine decarboxylase (ODC), under a constitutive promoter and to correlate various morphological and physiological abnormalities observed in response to reduced PA titres with a genome wide transcriptome analysis of ODC-knockdown tobacco RNAi line. The analysis has not only thrown up a number of candidate genes whose expression could be directly or indirectly affected by cellular PA levels but has also been very informative with regards to the regulation of PA pathway. Tobacco wild-type and transgenic lines were grown under the culture room conditions of 16 h light at 25°C Agilent Tobacco Gene Expression 4x44k K (AMADID: 021113) , Labeling kit: Agilent Quick-Amp labeling Kit (p/n5190-0442)
2016-08-01 | E-GEOD-75134 | biostudies-arrayexpress
Project description:Polyamines are aliphatic polycations that have emerged as important determinants of cell growth and viability in rapidly proliferating cells, including in the pathogenic protozoan parasite Leishmania donovani. In L. donovani, the polyamine spermidine is synthesized by the successive conversion of ornithine into putrescine (catalyzed by ornithine decarboxylase or ODC) and putrescine into spermidine (catalyzed by spermidine synthase or SPDSYN). Deletion of either ODC (del-odc) or SPDSYN (del-spdsyn) from the L. donovani genome renders these parasites auxotrophic for polyamines and these mutants are impaired in their ability to survive both in culture and within the mammalian host without the addition of exogenous polyamine supplementation. Significantly, del-odc parasites immediately cease proliferation after putrescine is removed from the culture media and perish within two weeks, while spermidine starved del-spdsyn mutants, which retain intracellular putrescine pools, show a slow-growth phenotype, and persist for several weeks in culture. To elucidate the key differences within the proteome of putrescine-starved del-odc cells and spermidine-starved del-spdsyn parasites, a shotgun quantitative proteomics approach was undertaken using TMT labeling and LC-MS/MS analysis. Briefly, three biological replicates each for mid-log phase del-odc and del-spdsyn promastigotes grown in the presence of exogenous putrescine (for del-odc) or spermidine (for del-spdsyn) supplementation were washed to remove the exogenous polyamine supplementation and incubated in polyamine-free media. At 24 and 48 h, cells from each biological replicate were isolated and prepared for tandem mass tag (TMT) labeling and downstream LC-MS/MS analyses. Peptides were identified using a database generated from the reference genome of L. donovani BPK282A1 strain. Changes in relative protein abundance for the polyamine-starved del-odc and del-spdsyn cell lines at 24 and 48 h were calculated by comparing aggregate total reporter ion intensities for each protein to that of the corresponding polyamine-supplemented 0-h timepoint.
2022-08-29 | PXD036349 | Pride
Project description:We report here a central role for polyamines in T cell differentiation and function. Deficiency in ornithine decarboxylase (ODC), a critical enzyme for polyamine synthesis, resulted in a profound failure of CD4+ T cells to adopt correct subset specification, underscored by ectopic expression of multiple cytokines and lineage- defining transcription factors across TH1, TH2, TH17, and Treg polarizing conditions, and enhanced colitogenic potential. T cells deficient in deoxyhypusine synthase (DHPS) or deoxyhypusine hydroxylase (DOHH), which sequentially utilize polyamines to generate hypusine, phenocopied Odc-deficient T cells, and mice in which T cells lacked Dhps or Dohh developed colitis. Polyamine-hypusine pathway enzyme deficiency caused widespread chromatin and transcriptional dysregulation accompanied by alterations in histone methylation, histone acetylation, and TCA cycle metabolites. Epigenetic modulation by 2-hydroxyglutarate, or histone acetyltransferase inhibition, restored CD4+ T cell subset specification. Thus, polyamine synthesis via hypusine is critical for maintaining the epigenome to focus TH cell subset fidelity.
2021-07-07 | GSE157597 | GEO
Project description:We report here a central role for polyamines in T cell differentiation and function. Deficiency in ornithine decarboxylase (ODC), a critical enzyme for polyamine synthesis, resulted in a profound failure of CD4+ T cells to adopt correct subset specification, underscored by ectopic expression of multiple cytokines and lineage- defining transcription factors across TH1, TH2, TH17, and Treg polarizing conditions, and enhanced colitogenic potential. T cells deficient in deoxyhypusine synthase (DHPS) or deoxyhypusine hydroxylase (DOHH), which sequentially utilize polyamines to generate hypusine, phenocopied Odc-deficient T cells, and mice in which T cells lacked Dhps or Dohh developed colitis. Polyamine-hypusine pathway enzyme deficiency caused widespread chromatin and transcriptional dysregulation accompanied by alterations in histone methylation, histone acetylation, and TCA cycle metabolites. Epigenetic modulation by 2-hydroxyglutarate, or histone acetyltransferase inhibition, restored CD4+ T cell subset specification. Thus, polyamine synthesis via hypusine is critical for maintaining the epigenome to focus TH cell subset fidelity.
2021-07-07 | GSE157596 | GEO
Project description:Polyamines are ubiquitous components of all living cells and their depletion usually causes cytostasis, a strategy employed for treatment of West-African trypanosomiasis. To evaluate polyamine-depletion as an antimalarial strategy, cytostasis caused by the co-inhibition of S-adenosylmethionine decarboxylase/ornithine decarboxylase (PfAdoMetDC/ODC) in Plasmodium falciparum was studied with a comprehensive transcriptome, proteome and metabolome investigation. Highly synchronized cultures were sampled just before and during cytostasis and a novel zero time point definition was used to enable interpretation of results in lieu of the developmentally regulated control of gene expression in P. falciparum. Transcriptome analysis revealed the occurrence of a generalized transcriptional arrest just prior to the growth arrest due to polyamine-depletion. However, the abundance of 538 transcripts was differentially affected and included three perturbation-specific compensatory transcriptional responses: the increased abundance of the transcripts for lysine decarboxylase (LDC) and ornithine aminotransferase (OAT) as well as the decreased abundance of that for S-adenosylmethionine synthetase (AdoMet synthetase). Moreover, the latter two compensatory mechanisms were confirmed on both protein and metabolite levels confirming their biological relevance. In contrast with previous reports, the results provide evidence that P. falciparumrespond to alleviate the detrimental effects of polyamine-depletion via regulation of its transcriptome and subsequently the proteome and metabolome. Keywords: functional genomics, time course, reference design, drug exposure, stress response, polyamine depletion, cytostasis
2008-12-11 | GSE13578 | GEO
Project description:Polyamines (PAs) and proteins have been demonstrated to be fundamental for in vitro shoot development of Cedrela fissilis. We evaluated the influence of 6-benzyladenine (BA) and putrescine (Put) on the growth of shoots, PA metabolism and proteomic profiles of C. fissilis. The longest shoots were obtained under 2.5 μM BA + 2.5 mM Put treatment. The inhibition of Put synthesis by D-arginine (D-arg) decreased the shoot length and reduced the endogenous contents of free Put and the activities of the Put biosynthesis enzymes arginine decarboxylase (ADC) and ornithine decarboxylase (ODC), resulting in reduced shoot growth. The ODC activity was higher than that of ADC, which is the main enzyme in the synthesis of Put in C. fissilis. Inhibition of Put synthesis affected the proteomic profile, reducing the accumulation of the ubiquitin receptor RAD23c, peroxidase 15, ADP-ribosylation factor 1, ADP-ribosylation factor-like protein 8a, profilin-4, profilin-2, glucan endo-1,3-beta-glucosidase, and expansin-like B1 and increasing the accumulation of V-type proton ATPase catalytic subunit A and methionine gamma-lyase, highlighting the relevance of these proteins in increasing shoot length. The transport protein SEC13 homolog B and the basic isoform glucan endo-1,3-beta-glucosidase, which are unique to shoots treated with BA+Put, are related to the promotion of shoot growth. Our results show that the modulation of endogenous PAs and proteomic profiles is necessary to regulate in vitro morphogenesis in C. fissilis. Moreover, the ODC enzyme is highly involved in the synthesis of Put during in vitro shoot development and is described for the first time in this species.
2023-09-06 | PXD036504 | Pride
Project description:Polyamines promote cellular proliferation, and their levels are controlled by ornithine decarboxylase antizyme 1 (Az1), through the proteasome-mediated, ubiquitin-independent degradation of ornithine decarboxylase (ODC), the rate-limiting enzyme of polyamine biosynthesis. Az1-mediated degradation of other substrates such as cyclin D1, DNp73 and Mps1 also regulate cell growth and centrosome amplification. Collectively, the currently known six Az1-substrates are all linked with tumorigenesis. To understand if Az1-mediated protein degradation might play a key role in regulating cellular process associated with tumorigenesis, we employed quantitative proteomics to identify novel Az1 substrates. Here, we describe the identification of LIM domain and Actin-binding protein 1 (LIMA1), also known as epithelial protein lost in neoplasm (EPLIN), as a new target of Az1. Interestingly, between the two isoforms of EPLIN-Alpha and -Beta, only EPLIN-Beta is the substrate of Az1, degraded in an ubiquitination-independent manner. Absence of Az1 led to elevated EPLIN-Beta levels, which caused enhanced cellular migration of Az1-/- cells. Consistently, higher levels of LIMA1 correlated with poorer overall survival of colorectal cancer patients. Taken together, this study identifies EPLIN-Beta as a novel Az1 substrate regulating cellular migration.
2023-06-08 | PXD039865 | Pride
Project description:Pancreatic ductal adenocarcinoma (PDA) cells have a distinct dependence on de novo ornithine synthesis from glutamine via ornithine aminotransferase (OAT), which supports polyamine synthesis and is required for tumor growth. This directional OAT activity is normally largely restricted to infancy and contrasts with the reliance of most adult normal tissues and other cancer types on arginase (ARG) to generate arginine-derived ornithine, the substrate for polyamine synthesis. This dependence associates with arginine depletion in PDA tumor microenvironment, and is driven by mutant KRAS, which induces the expression of OAT and polyamine synthesis enzymes, including the rate-limiting enzyme ornithine decarboxylase-1 (ODC1). Loss of OAT, but not ARG2, largely mimics loss of ODC1, altering the transcriptional profiles in PDA cells, which in turn correlate with alterations in open chromatin states.
2023-01-01 | GSE193411 | GEO
Project description:The specific role of polyamines in the testis physiology is not fully understood. Antizymes (OAZs) and antizyme inhibitors (AZINs) are modulators of ornithine decarboxylase (ODC), a key enzyme in polyamine biosynthesis and polyamine uptake. Although the three known OAZs are expressed in the testis, only OAZ3 is testis specific and has been proven to have an essential role in male fertility. Regarding the two existing AZINs, AZIN2 is the most abundantly expressed member in this gonad. Whereas previous studies suggested that AZIN2 might participate in mouse spermatogenesis, immunohistological analysis of human testicular sections revealed that AZIN2 is also detected in the steroidogenic Leydig cells but not in the germinal epithelium. In the present study, we found a close ontogenic similarity in the mRNA levels of OAZs and AZINs between mice and rats, but an opposite expression pattern of ODC activity. Further analysis of AZIN2 and OAZ3 in the testis of mice with different alterations in spermatogenesis and fertility, induced either genetically or pharmacologically, corroborated that both AZIN2 and OAZ3 are mainly expressed in the haploid germinal cells. Finally, by using transgenic mice with a truncated Azin2 gene fused to the bacterial lacZ gene, we studied the expression of Azin2 in testes, epididymides and spermatozoa. AZIN2 was detected in spermatids and spermatozoa, as well as in Leydig cells, and in epithelial epidydimal cells. Azin2 knock-out male mice were fertile; however, they showed marked decreases in testicular putrescine and plasma and testicular testosterone levels, and a dramatic reduction in the sperm motility. These results suggest an important role for AZIN2 in testicular cells by modulating polyamine concentrations, testosterone synthesis and sperm function. Overall, our data corroborate the relevance of polyamine regulation in spermatogenesis, where both AZIN2 and OAZ3 play fundamental roles. We used microarrays in order to detect how the disruption of Azin2 could affect overall gene expression in testis.
2018-10-20 | GSE121518 | GEO
Project description:Colonization by H. pylori is associated with a wide range of gastric diseases, ranging from superficial gastritis to more severe pathologies, including intestinal metaplasia and adenocarcinoma. The interplay of the host response and the pathogen affect the outcome of disease. One major component of the mucosal response to H. pylori is the activation of a strong, but inefficient immune response that fails to control the infection and frequently causes tissue damage. We have shown that polyamines can regulate H. pylori-induced inflammation. Chemical inhibition of ornithine decarboxylase (ODC), which generates putrescine from L-ornithine, reduces gastritis in mice and adenocarcinoma incidence in gerbils infected with H. pylori. However, we have also demonstrated that Odc deletion in myeloid cells enhances M1 macrophage activation and gastritis. Here we used a genetic approach to assess the specific role of gastric epithelial ODC during H. pylori infection. Deletion of Odc in gastric epithelial cells reduces gastritis, attenuates epithelial proliferaton, alters the metabolome, and dowregulates the expression of immune mediators induced by H. pylori. Inhibition of ODC activity in gastric epithelial cells reduces H. pylori-induced NF-B activation and CXCL8 mRNA expression. Chronic inflammation is a major risk factor for the progression to more severe pathologies associated with H. pylori infection and we now show that epithelial ODC plays an important role in mediating this inflammatory response.
2022-06-15 | MTBLS3235 | MetaboLights