ABOVEGROUND BIOMASS PRODUCTION AND NUTRIENT ACCUMULATION IN A FIVE YEAR OLD EUCALYPTUS GRANDIS AND E. UROPHYLLA PLANTATION

Nutrient concentrations in biomass components may vary with the component considered, plantation age and genetic material and its measurement is important to understand forestry nutrient management. Due to it, aboveground biomass production and nutrient accumulation and its potential removal through thinning in two species of Eucalyptus with five-year-old were evaluated in the southern of Brazil. Treatments were arranged in a randomized block design with three replications in a 2 x 4 factorial scheme, being 2 species (E. grandis and E. urophylla) and four diametric classes (C1: 3.0 - 8.8; C2: 8.9 - 14.7; C3: 14.8 - 20.6; C4: 20.7 -26.5 cm). Average annual accumulation of dry matter in both species was of 16.9 Mg ha-1. Biomass was mainly allocated in the stem (wood and bark). Trees’ canopy (branches and leaves) represent the smallest fractions, with only 14,3% of the total biomass. E. grandis showed highest values ​​of wood and leaf compartments. The highest content of N and K were found on the leaves, with N levels of 33.2 and 30.5 g.Kg-1 respectively to E. grandis and E. urophylla. Trees bark represent an important Ca and Mg reserve to the development of the plant, with values ​​of 18.02 and 3.24 g.kg-1 respectively. The mean concentration of Ca, N, K, Mg and P in the total biomass of the two species was of 528, 305, 200, 128 and 30 kg ha-1.As concentrações de nutrientes nos componentes da biomassa arbórea podem variar em função do componente, da idade da plantação e o material genético, e sua mensuração é importante para entender o manejo florestal de nutrientes do solo. A produção de biomassa da parte aérea, o acúmulo de nutrientes e o seu potencial de remoção em duas espécies de Eucalyptus com cinco anos de idade foram avaliados no sul do Brasil. Os tratamentos foram dispostos em delineamento de blocos casualizados com três repetições, em esquema fatorial 2 x 4, sendo duas espécies (E. grandis e E. urophylla) e quatro classes diamétricas (C1: 3,0 - 8,8; C2: 8,9 - 14,7; C3: 14,8 - 20,6; C4: 20,7 - 26,5 cm). O acúmulo médio anual de matéria seca em ambas as espécies foi de 16,9 Mg ha-1. A biomassa foi alocada principalmente no caule (madeira e casca). O dossel das árvores (ramos e folhas) representa as menores frações, com apenas 14,3% da biomassa total. E. grandis apresentou maiores valores de madeira e compartimentos foliares. Os maiores teores de N e K foram encontrados nas folhas, com níveis de N de 33,2 e 30,5 g.Kg-1, respectivamente, para E. grandis e E. urophylla. A casca das árvores representa uma importante reserva de Ca e Mg para o desenvolvimento da planta, com valores de 18,02 e 3,24 g.kg-1, respectivamente. As concentrações médias de Ca, N, K, Mg e P na biomassa total das duas espécies foram de 528, 305, 200, 128 e 30 kg ha-1

Clinical and molecular characterization of patients fulfilling Chompret criteria for Li-Fraumeni syndrome in Southern Brazil

Li-Fraumeni syndrome (LFS) is an autosomal dominant cancer predisposition syndrome caused by pathogenic germline variants in the TP53 gene, characterized by a predisposition to the development of a broad spectrum of tumors at an early age. The core tumors related to LFS are bone and soft tissue sarcomas, premenopausal breast cancer, brain tumors, adre nocortical carcinomas (ACC), and leukemias. The revised Chompret criteria has been widely used to establish clinical suspicion and support TP53 germline variant testing and LFS diag nosis. Information on TP53 germline pathogenic variant (PV) prevalence when using Chom pret criteria in South America and especially in Brazil is scarce. Therefore, the aim of this study was to characterize patients that fulfilled these specific criteria in southern Brazil, a region known for its high population frequency of a founder TP53 variant c.1010G>A (p. Arg337His), as known as R337H. TP53 germline testing of 191 cancer-affected and indepen dent probands with LFS phenotype identified a heterozygous pathogenic/likely pathogenic variant in 26 (13.6%) probands, both in the DNA binding domain (group A) and in the oligo merization domain (group B) of the gene. Of the 26 carriers, 18 (69.23%) were R337H het erozygotes. Median age at diagnosis of the first tumor in groups A and B differed significantly in this cohort: 22 and 2 years, respectively (P = 0.009). The present study shows the clinical heterogeneity of LFS, highlights particularities of the R337H variant and underscores the need for larger collaborative studies to better define LFS prevalence, clinical spectrum and penetrance of different germline TP53 pathogenic variants

Induction of dsRNA-activated protein kinase links mitochondrial unfolded protein response to the pathogenesis of intestinal inflammation

Inflammatory bowel diseases (IBDs) feature multiple cellular stress responses, including endoplasmic reticulum (ER) unfolded protein responses (UPRs). UPRs represent autoregulatory pathways that adjust organelle capacity to cellular demand. A similar mechanism, mitochondrial UPR (mtUPR), has been described for mitochondria. ER UPR in intestinal epithelial cells (IECs) contributes to the development of intestinal inflammation, and since mitochondrial alterations and dysfunction are implicated in the pathogenesis of IBDs, the authors characterised mtUPR in the context of intestinal inflammation

Genetic and molecular characterization of bud dormancy in apple: deciphering candidate gene roles in dormancy regulation

International audienceDormancy is an adaptive mechanism that enables plants to survive unfavorable climatic conditions, for example during winter, and allows flowering to occur only when the conditions are more permissive, typically in spring. The production of temperate fruits, such as apple (Malus x domestica Borkh.), is closely related to bud dormancy, given that a well-adjusted dormancy cycle is crucial for the achievement of their full genetic potential. Unlike other temperate fruit crops, dormancy in apple is assumed to be triggered by exposure to low temperatures and not photoperiodic changes. Therefore, the predicted impact of the ongoing climate change will result in difficulties for apple production. The mechanisms that regulate dormancy are highly heritable, suggesting a strong genetic control of this trait. At the molecular level, bud dormancy in apple is probably controlled by a group of genes encoding MADS-box transcription factors commonly known as Dormancy-Associated MADS-box (DAM) genes. However, their precise mode of action and integration in gene networks controlling dormancy progression in apple are still unknown. In this context, the present work aims to prospect and characterize the role of DAM and other flowering-time related genes in the dormancy process of apple through complementary genetic and molecular approaches. At the genetic level, we are exploring an apple core collection established in France, and several cultivars from Brazil, in order to identify allelic variation present in genes involved in bud dormancy and flowering control. For this purpose, we are developing a target capture sequencing approach on key gene families involved in dormancy and flowering regulation. At the molecular level, we are studying how DAM proteins are organized in transcriptional complexes by performing yeast two-hybrid assays. Furthermore, we are carrying over chromatin immunoprecipitation followed by sequencing (ChIP-seq) experiments in order to identify their genome-wide transcriptional targets. Together, these studies will allow a better characterization of key processes in dormancy molecular control, as well as to identify possible biotechnological resources for application in breeding programs