Transcriptional profiling of Neurospora crassa Δmak-2 reveals that mitogen-activated protein kinase MAK-2 participates in the phosphate signaling pathway

AbstractThe filamentous fungus Neurospora crassa is an excellent model system for examining molecular responses to ambient signals in eukaryotic microorganisms. Inorganic phosphate (Pi) is an essential growth-limiting nutrient in nature and is crucial for the synthesis of nucleic acids and the flow of genetic information. The genetic and molecular mechanisms controlling the response to Pi starvation in N. crassa include at least four genes (nuc-2, preg, pogv, and nuc-1), which are involved in a hierarchical regulatory activation network. In a previous work, we identified a number of genes modulated by NUC-2 protein, including the mak-2 gene, which codes for a mitogen-activated protein kinase (MAPK), suggesting its participation in the phosphate signaling pathway. Thus, to identify other genes involved in metabolic responses to exogenous phosphate sensing and the functioning of the MAPK MAK-2, we performed microarray experiments using a mak-2 knockout strain (Δmak-2) grown under phosphate-shortage conditions by comparing its transcription profile to that of a control strain grown in low- and high-phosphate cultures. These experiments revealed 912 unique differentially expressed genes involved in a number of physiological processes related to phosphate transport, metabolism, and regulation as well as posttranslational modification of proteins, and MAPK signaling pathways. Quantitative Real-time PCR gene expression analysis of 18 selected genes, using independent RNA samples, validated our microarray results. A high Pearson correlation between microarray and quantitative Real-time PCR data was observed. The analysis of these differentially expressed genes in the Δmak-2 strain provide evidence that the mak-2 gene participates in the hierarchical phosphate-signaling pathway in N. crassa in addition to its involvement in other metabolic routes such as the isoprenylation pathway, thus revealing novel aspects of the N. crassa phosphorus-sensing network

Qualidade sanitária e fisiológica de sementes de abóbora variedade menina Brasileira.

O trabalho teve como objetivos avaliar e correlacionar a qualidade sanitária e fisiológica de sementes de abóbora, variedade Menina Brasileira (Cucurbita moschata.). Foram avaliados dois lotes de sementes de abóbora produzidas no sistema agroecológico e quatro no sistema convencional, com e sem tratamento químico. Os lotes foram submetidos aos testes de sanidade, seguindo a metodologia do “Blotter test”, com congelamento, germinação e vigor (primeira contagem, índice de velocidade de germinação, envelhecimento acelerado e emergência de plântulas). Os resultados indicaram a separação dos lotes de diferentes origens a partir da qualidade sanitária e fisiológica, onde as maiores incidências de fungos foram observadas nos lotes agroecológicos e o maior potencial fisiológico foi observado nos lotes de origem convencional não tratados. Foram encontrados os fungos Fusarium oxysporum, Alternaria alternata, Cladosporium cucumerinum, Aspergillus niger, Penicillium digitatum, Rhizopus stolonifer e Phoma terrestris. A qualidade sanitária não interferiu na qualidade fisiológica das sementes de abóbora, variedade Menina Brasileira

Anisotropy studies around the galactic centre at EeV energies with the Auger Observatory

Data from the Pierre Auger Observatory are analyzed to search for anisotropies near the direction of the Galactic Centre at EeV energies. The exposure of the surface array in this part of the sky is already significantly larger than that of the fore-runner experiments. Our results do not support previous findings of localized excesses in the AGASA and SUGAR data. We set an upper bound on a point-like flux of cosmic rays arriving from the Galactic Centre which excludes several scenarios predicting sources of EeV neutrons from Sagittarius $A$. Also the events detected simultaneously by the surface and fluorescence detectors (the `hybrid' data set), which have better pointing accuracy but are less numerous than those of the surface array alone, do not show any significant localized excess from this direction.Comment: Matches published versio

An Integrated TCGA Pan-Cancer Clinical Data Resource to Drive High-Quality Survival Outcome Analytics

For a decade, The Cancer Genome Atlas (TCGA) program collected clinicopathologic annotation data along with multi-platform molecular profiles of more than 11,000 human tumors across 33 different cancer types. TCGA clinical data contain key features representing the democratized nature of the data collection process. To ensure proper use of this large clinical dataset associated with genomic features, we developed a standardized dataset named the TCGA Pan-Cancer Clinical Data Resource (TCGA-CDR), which includes four major clinical outcome endpoints. In addition to detailing major challenges and statistical limitations encountered during the effort of integrating the acquired clinical data, we present a summary that includes endpoint usage recommendations for each cancer type. These TCGA-CDR findings appear to be consistent with cancer genomics studies independent of the TCGA effort and provide opportunities for investigating cancer biology using clinical correlates at an unprecedented scale. Analysis of clinicopathologic annotations for over 11,000 cancer patients in the TCGA program leads to the generation of TCGA Clinical Data Resource, which provides recommendations of clinical outcome endpoint usage for 33 cancer types