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A close relationship has been demonstrated between genomic complexity and clinical outcome in uterine smooth muscle tumors. We studied the genomic profiles by array-CGH of 28 fumarate hydratase deficient leiomyomas and 37 leiomyomas with bizarre nuclei (LMBN) from 64 patients. Follow-up was available for 46 patients (from three to 249 months, mean 87.3 months). All patients were alive without evidence of disease. For 51 array-CGH interpretable tumors the mean Genomic Index (GI) was 16.4 (median: 9.8; from 1 to 57.8), significantly lower than the mean GI in LMS (mean GI 51.8, p < 0.001). We described three groups: (1) a group with FH deletion (24/58) with low GI (mean GI: 11 vs. 22,4, p = 0.02), (2) a group with TP53 deletion (17/58) with higher GI (22.4 vs. 11 p = 0.02), and (3) a group without genomic events on FH or TP53 genes (17/58) (mean GI:18.3; from 1 to 57.8). Because none of these tumors recurred and none showed morphological features of LMS we concluded that GI at the cut-off of 10 was not applicable in these subtypes of LM. By integration of all those findings, a GI <10 in LMBN remains a valuable argument for benignity. Conversely, in LMBN a GI >10 or alteration in tumor suppressor genes, should not alone warrant a diagnosis of malignancy. Nine tumors were tested with Nanocind CINSARC® signature and all were classified in low risk of recurrence. We propose, based on our observations, a diagnostic approach of these challenging lesions.
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Leiomioma , Neoplasias Uterinas , Femenino , Humanos , Neoplasias Uterinas/genética , Neoplasias Uterinas/patología , Fumarato Hidratasa/genética , Leiomioma/genética , Leiomioma/patología , Genes p53 , GenómicaRESUMEN
BACKGROUND: Real-world data (RWD) related to the health status and care of cancer patients reflect the ongoing medical practice, and their analysis yields essential real-world evidence. Advanced information technologies are vital for their collection, qualification, and reuse in research projects. METHODS: UNICANCER, the French federation of comprehensive cancer centres, has innovated a unique research network: Consore. This potent federated tool enables the analysis of data from millions of cancer patients across eleven French hospitals. RESULTS: Currently operational within eleven French cancer centres, Consore employs natural language processing to structure the therapeutic management data of approximately 1.3 million cancer patients. These data originate from their electronic medical records, encompassing about 65 million medical records. Thanks to the structured data, which are harmonized within a common data model, and its federated search tool, Consore can create patient cohorts based on patient or tumor characteristics, and treatment modalities. This ability to derive larger cohorts is particularly attractive when studying rare cancers. CONCLUSIONS: Consore serves as a tremendous data mining instrument that propels French cancer centres into the big data era. With its federated technical architecture and unique shared data model, Consore facilitates compliance with regulations and acceleration of cancer research projects.
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Investigación Biomédica , Neoplasias , Humanos , Minería de Datos , Registros Electrónicos de Salud , Neoplasias/terapia , LenguajeRESUMEN
BACKGROUND: Soft-tissue sarcomas (STS) represent a heterogeneous group of rare tumors including more than 70 different histological subtypes. High throughput molecular analysis (next generation sequencing exome [NGS]) is a unique opportunity to identify driver mutations that can change the usual one-size-fits-all treatment paradigm to a patient-driven therapeutic strategy. The primary objective of the MULTISARC trial is to assess whether NGS can be conducted for a large proportion of metastatic STS participants within a reasonable time, and, secondarily to determine whether a NGS-guided therapeutic strategy improves participant's outcome. METHODS: This is a randomized, multicentre, phase II/III trial inspired by the design of umbrella and biomarker-driven trials. The setting plans up to 17 investigational centres across France and the recruitment of 960 participants. Participants aged at least 18 years, with unresectable locally advanced and/or metastatic STS confirmed by the French sarcoma pathological reference network, are randomized according to 1:1 allocation ratio between the experimental arm "NGS" and the standard "No NGS". NGS will be considered feasible if (i) NGS results are available and interpretable, and (ii) a report of exome sequencing including a clinical recommendation from a multidisciplinary tumor board is provided to investigators within 7 weeks from reception of the samples on the biopathological platform. A feasibility rate of more than 70% is expected (null hypothesis: 70% versus alternative hypothesis: 80%). In terms of care, participants randomized in "No NGS" arm and who fail treatment will be able to switch to the NGS arm at the request of the investigator. DISCUSSION: The MULTISARC trial is a prospective study designed to provide high-level evidence to support the implementation of NGS in routine clinical practice for advanced STS participants, on a large scale. TRIAL REGISTRATION: clinicaltrial.gov NCT03784014 .
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Secuenciación de Nucleótidos de Alto Rendimiento , Sarcoma/genética , Neoplasias de los Tejidos Blandos/genética , Adulto , Análisis Costo-Beneficio , Estudios de Factibilidad , Francia , Humanos , Estudios Prospectivos , Tamaño de la Muestra , Sarcoma/patología , Sarcoma/terapia , Neoplasias de los Tejidos Blandos/patología , Neoplasias de los Tejidos Blandos/terapia , Factores de Tiempo , Secuenciación del ExomaRESUMEN
PURPOSE: Many institutions throughout the world have launched precision medicine initiatives in oncology, and a large amount of clinical and genomic data is being produced. Although there have been attempts at data sharing with the community, initiatives are still limited. In this context, a French task force composed of Integrated Cancer Research Sites (SIRICs), comprehensive cancer centers from the Unicancer network (one of Europe's largest cancer research organization), and university hospitals launched an initiative to improve and accelerate retrospective and prospective clinical and genomic data sharing in oncology. MATERIALS AND METHODS: For 5 years, the OSIRIS group has worked on structuring data and identifying technical solutions for collecting and sharing them. The group used a multidisciplinary approach that included weekly scientific and technical meetings over several months to foster a national consensus on a minimal data set. RESULTS: The resulting OSIRIS set and event-based data model, which is able to capture the disease course, was built with 67 clinical and 65 omics items. The group made it compatible with the HL7 Fast Healthcare Interoperability Resources (FHIR) format to maximize interoperability. The OSIRIS set was reviewed, approved by a National Plan Strategic Committee, and freely released to the community. A proof-of-concept study was carried out to put the OSIRIS set and Common Data Model into practice using a cohort of 300 patients. CONCLUSION: Using a national and bottom-up approach, the OSIRIS group has defined a model including a minimal set of clinical and genomic data that can be used to accelerate data sharing produced in oncology. The model relies on clear and formally defined terminologies and, as such, may also benefit the larger international community.
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Genómica , Difusión de la Información , Humanos , Oncología Médica , Estudios Prospectivos , Estudios RetrospectivosRESUMEN
Alterations of genes encoding subunits of the BAF/PBAF complexes are among the most frequent gene aberrations in human cancer. Such alterations have been shown to have an impact on tumor microenvironnement and on the capacity of tumors to respond to immune-checkpoint inhibitors (ICI). We analysed the clinical and genetic data from 43,728 patients accessed through cBioportal. The mutational frequencies of ARID1A, ARID1B, ARID2, PBRM1, SMARCA4, and SMARCB1 were 6.6%, 3,4, 3.4, 3.2, 4.1, and 1.2%, respectively. We then investigated the association between the presence of least one nonsynonymous somatic mutation of ARID1A, ARID1B, ARID2, PBRM1, SMARCA4, or SMARCB1 and overall survival of 1661 patients treated with an ICI. Across the entire cohort, patients with BAF/PBAF mutated tumors have a statistically significant improvement in overall survival (median overall survival: 28 months [95% CI 21.6-34.3] versus 15 months [95% CI 12.9-17.0], p < 0.0001). When tumor mutational burden was adjusted for a multivariable Cox regression analysis, BAF/PBAF gene mutations remained an independent prognostic factor for overall survival in patients treated ICI. Our results establish a relationship between mutations in key genes encoding for components of the BAF/PBAF complex and outcome of patients treated with ICI. Further studies are needed to elucidate the underlying mechanisms of this interaction.
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BACKGROUND: Whole exome sequencing and RNA sequencing (WES/RNASeq) should now be implemented in the clinical practice in order to increase access to optimal care for cancer patients. Providing results to Tumour Boards in a relevant time frame-that is, compatible with the clinical pathway-is crucial. Assessing the feasibility of this implementation in the French care system is the primary objective of the Multipli study, as one of the four pilot projects of the national France Genomic Medicine 2025 (FGM 2025) plan. The Multipli study encompasses two innovative trials which will be driven in around 2400 patients suffering from a soft-tissue sarcoma (Multisarc) or a metastatic colorectal carcinoma (Acompli). METHODS: Prior to launching the FGM 2025 cancer pilot study itself, the performance of the Multipli genomic workflow has been evaluated through each step, from the samples collection to the Molecular Tumour Board (MTB) report. Two Multipli-assigned INCa-labelled molecular genetics centres, the CEA-CNRGH sequencing platform and the Institut Bergonié's Bioinformatics Platform were involved in a multicentric study. The duration of each step of the genomic workflow was monitored and bottlenecks were identified. RESULTS: Thirty barriers which could affect the quality of the samples, sequencing results and the duration of each step of the genomic pathway were identified and mastered. The global turnaround time from the sample reception to the MTB report was of 44 calendar days. CONCLUSION: Our results demonstrate the feasibility of tumour genomic analysis by WES/RNASeq within a time frame compatible with the current cancer patient care. Lessons learnt from the Multipli WES/RNASeq Platforms Workflow Study will constitute guidelines for the forthcoming Multipli study and more broadly for the future clinical routine practice in the first two France Genomic Medicine 2025 platforms.
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Secuenciación de Nucleótidos de Alto Rendimiento , Neoplasias , Estudios de Factibilidad , Francia , Genómica , Humanos , Proyectos PilotoRESUMEN
Soft-tissue sarcomas represent a heterogeneous group of cancer, with more than 50 histological subtypes1,2. The clinical presentation of patients with different subtypes is often atypical, and responses to therapies such as immune checkpoint blockade vary widely3,4. To explain this clinical variability, here we study gene expression profiles in 608 tumours across subtypes of soft-tissue sarcoma. We establish an immune-based classification on the basis of the composition of the tumour microenvironment and identify five distinct phenotypes: immune-low (A and B), immune-high (D and E), and highly vascularized (C) groups. In situ analysis of an independent validation cohort shows that class E was characterized by the presence of tertiary lymphoid structures that contain T cells and follicular dendritic cells and are particularly rich in B cells. B cells are the strongest prognostic factor even in the context of high or low CD8+ T cells and cytotoxic contents. The class-E group demonstrated improved survival and a high response rate to PD1 blockade with pembrolizumab in a phase 2 clinical trial. Together, this work confirms the immune subtypes in patients with soft-tissue sarcoma, and unravels the potential of B-cell-rich tertiary lymphoid structures to guide clinical decision-making and treatments, which could have broader applications in other diseases.
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Linfocitos B/inmunología , Inmunoterapia , Sarcoma/tratamiento farmacológico , Sarcoma/inmunología , Estructuras Linfoides Terciarias/inmunología , Anticuerpos Monoclonales Humanizados/farmacología , Anticuerpos Monoclonales Humanizados/uso terapéutico , Linfocitos T CD8-positivos/inmunología , Estudios de Cohortes , Células Dendríticas Foliculares/inmunología , Humanos , Mutación , Fenotipo , Pronóstico , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Reproducibilidad de los Resultados , Sarcoma/clasificación , Sarcoma/patología , Tasa de Supervivencia , Microambiente TumoralRESUMEN
[This corrects the article DOI: 10.1128/MRA.00872-18.].
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Starmerella bacillaris is an ascomycetous yeast ubiquitously present in grapes and fermenting grape musts. In this report, we present the draft genome sequence of the S. bacillaris type strain CBS 9494, isolated from sweet botrytized wines, which will contribute to the study of this genetically heterogeneous wine yeast species.
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Importance: Patients with advanced soft-tissue sarcomas (STS) have a median overall survival of less than 18 months. Identification of molecular abnormalities for which targeted therapies are available or can be developed is critical for improving patient outcomes. Objective: To characterize targetable genomic alterations (GAs) in patients with STS. Design, Setting, and Participants: This cross-sectional study of next-generation sequencing results from 584 patients with STS included in the AACR GENIE Database. Main Outcomes and Measures: Presence of targetable GAs in STS. Results: Of 584 patients included in the analysis, 294 (50.3%) were men and 290 (49.7%) were women, with a median age of 56 years (range, 18-89 years). There were 331 (57%) patients with complex genomics sarcomas, 144 (25%) with translocation-related sarcomas, and 112 (18%) with other sarcomas (inactivating mutation, simple amplicon). A total of 2697 alterations were identified in 451 genes (1154 substitutions, 765 gene amplifications, 364 short indels and splicing variants, 346 gene homozygous deletions, and 68 gene rearrangements) with a median of 4 (1-53) per case. In order of frequency, the 20 genes most often altered were: TP53, MDM2, CDK4, RB1, ATRX, CDKN2A, PTEN, NF1, CDKN2B, KMT2D, GLI1, ATM, TERT, PI3KCA, NOTCH1, MAP2K4, ERBB4, ARID1A, TSC2, and TNFAIP3. At least 1 targetable GA was found in 239 cases (41%) with a statistically significant higher number in other and complex genomics sarcomas than in translocation-related sarcomas (respectively other: n=89, 82%, complex: n = 131, 40%, translocation: n = 19, 13%; χ2 test, P < .001). Conclusions and Relevance: Up to 41% of STS harbored at least 1 clinically relevant GA with potential to influence and personalize therapy. Comprehensive genomic profiling can identify novel treatment paradigms to address the limited options and poor prognoses of patients with STS.
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Antineoplásicos/uso terapéutico , Biomarcadores de Tumor/antagonistas & inhibidores , Terapia Molecular Dirigida/métodos , Sarcoma/tratamiento farmacológico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/genética , Estudios Transversales , Femenino , Genómica/métodos , Humanos , Masculino , Persona de Mediana Edad , Medicina de Precisión/métodos , Sarcoma/genética , Adulto JovenRESUMEN
Previous precision medicine studies have investigated conventional molecular techniques and/or limited sets of gene alterations. The aim of this study was to describe the impact of the next-generation sequencing of the largest panel of genes used to date in tumour tissue and blood in the context of institutional molecular screening programmes. DNA analysis was performed by next-generation sequencing using a panel of 426 cancer-related genes and by comparative genomic hybridization from formalin-fixed and paraffin-embedded archived tumour samples when available or from fresh tumour samples. Five hundred sixty-eight patients were enrolled. The median number of prior lines of treatment was 2 (range 0-9). The most common primary tumour types were lung (16.9%), colorectal (14.4%), breast (10.6%), ovarian (10.2%) and sarcoma (10.2%). The median patient age was 63 years (range 19-88). A total of 292 patients (51.4%) presented with at least one actionable genetic alteration. The 20 genes most frequently altered were TP53, CDKN2A, KRAS, PTEN, PI3KCA, RB1, APC, ERBB2, MYC, EGFR, CDKN2B, ARID1A, SMAD4, FGFR1, MDM2, BRAF, ATM, CCNE1, FGFR3 and FRS2. One hundred fifty-nine patients (28%) were included in early phase trials. The treatment was matched with a tumour profile in 86 cases (15%). The two main reasons for non-inclusion were non-progressive disease (31.5%) and general status deterioration (25%). Twenty-eight percent of patients presented with a growth modulation index (time to progression under the early phase trial treatment/time to progression of the previous line of treatment) >1.3.Extensive molecular profiling using high-throughput techniques allows for the identification of actionable mutations in the majority of cases and is associated with substantial clinical benefit in up to one in four patients.
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Hibridación Genómica Comparativa , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Neoplasias/genética , Adulto , Anciano , Anciano de 80 o más Años , Dosificación de Gen , Fusión Génica , Humanos , Persona de Mediana Edad , Mutación , Medicina de Precisión/métodos , Análisis de Secuencia de ADN , Adulto JovenRESUMEN
THE BIG NATIONAL DATABASES AND STUDIES ON REAL WORLD DATA: EXAMPLE OF SARCOMAS IN FRANCE: Sarcomas are rare and heterogeneous tumours, and improvement of knowledge and of patient management need to gather and share data and biological material. The French sarcoma database stores in a warehouse clinical, pathological, molecular, therapeutic and follow-up data as well as data on samples and medical practices. This database and the national structured networks constitute major tools for the French Sarcoma Group.
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Bases de Datos Factuales , Sarcoma , Bases de Datos Factuales/estadística & datos numéricos , Francia , Humanos , Sarcoma/genética , Sarcoma/patología , Sarcoma/terapiaRESUMEN
In fruit tree species, many important traits have been characterized genetically by using single-family descent mapping in progenies segregating for the traits. However, most mapped loci have not been sufficiently resolved to the individual genes due to insufficient progeny sizes for high resolution mapping and the previous lack of whole-genome sequence resources of the study species. To address this problem for Plum Pox Virus (PPV) candidate resistance gene identification in Prunus species, we implemented a genome-wide association (GWA) approach in apricot. This study exploited the broad genetic diversity of the apricot (Prunus armeniaca) germplasm containing resistance to PPV, next-generation sequence-based genotyping, and the high-quality peach (Prunus persica) genome reference sequence for single nucleotide polymorphism (SNP) identification. The results of this GWA study validated previously reported PPV resistance quantitative trait loci (QTL) intervals, highlighted other potential resistance loci, and resolved each to a limited set of candidate genes for further study. This work substantiates the association genetics approach for resolution of QTL to candidate genes in apricot and suggests that this approach could simplify identification of other candidate genes for other marked trait intervals in this germplasm.
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Enfermedades de las Plantas/genética , Enfermedades de las Plantas/virología , Virus Eruptivo de la Ciruela/patogenicidad , Prunus armeniaca/genética , Prunus armeniaca/virología , Mapeo Cromosómico , Resistencia a la Enfermedad/genética , Genética de Población , Genoma de Planta , Estudio de Asociación del Genoma Completo , Interacciones Huésped-Patógeno/genética , Desequilibrio de Ligamiento , Polimorfismo de Nucleótido Simple , Sitios de Carácter CuantitativoRESUMEN
The RADseq technology allows researchers to efficiently develop thousands of polymorphic loci across multiple individuals with little or no prior information on the genome. However, many questions remain about the biases inherent to this technology. Notably, sequence misalignments arising from paralogy may affect the development of single nucleotide polymorphism (SNP) markers and the estimation of genetic diversity. We evaluated the impact of putative paralog loci on genetic diversity estimation during the development of SNPs from a RADseq dataset for the nonmodel tree species Robinia pseudoacacia L. We sequenced nine genotypes and analyzed the frequency of putative paralogous RAD loci as a function of both the depth of coverage and the mismatch threshold allowed between loci. Putative paralogy was detected in a very variable number of loci, from 1% to more than 20%, with the depth of coverage having a major influence on the result. Putative paralogy artificially increased the observed degree of polymorphism and resulting estimates of diversity. The choice of the depth of coverage also affected diversity estimation and SNP validation: A low threshold decreased the chances of detecting minor alleles while a high threshold increased allelic dropout. SNP validation was better for the low threshold (4×) than for the high threshold (18×) we tested. Using the strategy developed here, we were able to validate more than 80% of the SNPs tested by means of individual genotyping, resulting in a readily usable set of 330 SNPs, suitable for use in population genetics applications.
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The yeast Candida zemplinina (Starmerella bacillaris) is frequently isolated from grape and wine environments. Its enological use in mixed fermentation with Saccharomyces cerevisiae has been extensively investigated these last few years, and several interesting features including low ethanol production, fructophily, glycerol and other metabolites production, have been described. In addition, molecular tools allowing the characterization of yeast populations have been developed, both at the inter- and intraspecific levels. However, most of these fingerprinting methods are not compatible with population genetics or ecological studies. In this work, we developed 10 microsatellite markers for the C. zemplinina species that were used for the genotyping of 163 strains from nature or various enological regions (28 vineyards/wineries from seven countries). We show that the genetic diversity of C. zemplinina is shaped by geographical localization. Populations isolated from winemaking environments are quite diverse at the genetic level: neither clonal-like behaviour nor specific genetic signature were associated with the different vineyards/wineries. Altogether, these results suggest that C. zemplinina is not under selective pressure in winemaking environments.
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Candida/genética , Genoma Fúngico/genética , Repeticiones de Microsatélite/genética , Vitis/microbiología , Vino/microbiología , Secuencia de Bases , Candida/clasificación , Candida/metabolismo , ADN de Hongos/genética , Etanol/metabolismo , Fermentación , Fructosa/metabolismo , Variación Genética/genética , Genotipo , Técnicas de Genotipaje , Geografía , Glicerol/metabolismo , Saccharomyces cerevisiae/metabolismo , Selección Genética/genética , Análisis de Secuencia de ADNRESUMEN
Seedling establishment is a crucial phase during plant development when the germinating heterotrophic embryo switches to autotrophic growth and development. Positive regulators of embryonic development need to be turned off, while the cell cycle machinery is activated to allow cell cycle entry and organ primordia initiation. However, it is not yet understood how the molecular mechanisms responsible for the onset of cell division, metabolism changes and cell differentiation are coordinated during this transition. Here, we demonstrate that the Arabidopsis thaliana RETINOBLASTOMA-RELATED protein (RBR) ortholog of the animal tumor suppressor retinoblastoma (pRB) not only controls the expression of cell cycle-related genes, but is also required for persistent shut-down of late embryonic genes by increasing their histone H3K27 trimethylation. Seedlings with reduced RBR function arrest development after germination, and stimulation with low amounts of sucrose induces transcription of late embryonic genes and causes ectopic cell division. Our results suggest a model in which RBR acts antagonistically to sucrose by negatively regulating the cell cycle and repressing embryonic genes. Thus, RBR is a positive regulator of the developmental switch from embryonic heterotrophic growth to autotrophic growth. This establishes RBR as a new integrator of metabolic and developmental decisions.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/embriología , Procesos Autotróficos/fisiología , Ciclo Celular/fisiología , Regulación del Desarrollo de la Expresión Génica/fisiología , Regulación de la Expresión Génica de las Plantas/fisiología , Plantones/embriología , Inmunoprecipitación de Cromatina , Metilación de ADN/fisiología , Cartilla de ADN/genética , Electroforesis en Gel de Poliacrilamida , Fluorescencia , Regulación del Desarrollo de la Expresión Génica/genética , Regulación de la Expresión Génica de las Plantas/genética , Glucosa/metabolismo , Histonas/metabolismo , Immunoblotting , Espectrometría de Masas , Análisis por Micromatrices , Microscopía Electrónica de Rastreo , Modelos Biológicos , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
Several genes involved in the regulation of postembryonic organ initiation and growth have been identified. However, it remains largely unclear how developmental cues connect to the cell cycle. RETINOBLASTOMA RELATED (RBR) is a plant homolog of the tumor suppressor Retinoblastoma (pRb), which is a key regulator of the cell cycle. Using inducible RNA interference (RNAi) against Arabidopsis thaliana RBR (RBRi), we reduced RBR expression levels at different stages of plant development. Conditional reduction or loss of RBR function disrupted cell division patterns, promoted context-dependent cell proliferation, and negatively influenced establishment of cell differentiation. Several lineages of toti- and pluripotent cells, including shoot apical meristem stem cells, meristemoid mother cells, and procambial cells, failed to produce appropriately differentiated cells. Meristem activity was altered, leading to a disruption of the CLAVATA-WUSCHEL feedback loop and inhibition of lateral organ formation. Release of RBR from RNAi downregulation restored meristem activity. Gene profiling analyses soon after RBRi induction revealed that a change in RBR homeostasis is perceived as a stress, even before genes regulated by RBR-E2F become deregulated. The results establish RBR as a key cell cycle regulator required for coordination of cell division, differentiation, and cell homeostasis.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/crecimiento & desarrollo , Diferenciación Celular , Células Madre/citología , Arabidopsis/genética , Proteínas de Arabidopsis/genética , División Celular , ADN de Plantas/genética , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Meristema/citología , Meristema/crecimiento & desarrollo , Hojas de la Planta/citología , Interferencia de ARN , Transformación GenéticaRESUMEN
The role of a subfamily of lipid globule-associated proteins, referred to as plant fibrillins (FIB1a, -1b, -2), was determined using a RNA interference (RNAi) strategy. We show that Arabidopsis plants with reduced levels of these plastid structural proteins are impaired in long-term acclimation to environmental constraint, namely photooxidative stress imposed by high light combined with cold. As a result, their photosynthetic apparatus is inefficiently protected. This leads to the prevalence of an abnormal granal and stromal membrane arrangement, as well as higher photosystem II photoinhibition under stress. The visible phenotype of FIB1-2 RNAi lines also includes retarded shoot growth and a deficit in anthocyanin accumulation under stress. All examined phenotypic effects of lower FIB levels are abolished by jasmonate (JA) treatment. An atypical expression pattern of several JA-induced genes was observed in RNAi plants. A JA-deficient mutant was found to share similar stress phenotypic characteristics with FIB RNAi plants. We conclude a new physiological role for JA, namely acclimation of chloroplasts, and that light/cold stress-related JA biosynthesis is conditioned by the accumulation of plastoglobule-associated FIB1-2 proteins. Consistent correlative data suggest that this FIB effect is mediated by plastoglobule (and triacylglycerol) accumulation as the potential site for initiating the chloroplast stress-related JA biosynthesis.