A Unifying Framework for Understanding Biological Structures and Functions Across Levels of Biological Organization.

The relationship between structure and function is a major constituent of the rules of life. Structures and functions occur across all levels of biological organization. Current efforts to integrate conceptual frameworks and approaches to address new and old questions promise to allow a more holistic and robust understanding of how different biological functions are achieved across levels of biological organization. Here, we provide unifying and generalizable definitions of both structure and function that can be applied across all levels of biological organization. However, we find differences in the nature of structures at the organismal level and below as compared to above the level of the organism. We term these intrinsic and emergent structures, respectively. Intrinsic structures are directly under selection, contributing to the overall performance (fitness) of the individual organism. Emergent structures involve interactions among aggregations of organisms and are not directly under selection. Given this distinction, we argue that while the functions of many intrinsic structures remain unknown, functions of emergent structures are the result of the aggregate of processes of individual organisms. We then provide a detailed and unified framework of the structure-function relationship for intrinsic structures to explore how their unknown functions can be defined. We provide examples of how these scalable definitions applied to intrinsic structures provide a framework to address questions on structure-function relationships that can be approached simultaneously from all subdisciplines of biology. We propose that this will produce a more holistic and robust understanding of how different biological functions are achieved across levels of biological organization.

Antiviral RNA silencing suppression activity of Tomato spotted wilt virus NSs protein.

In addition to regulating gene expression, RNA silencing is an essential antiviral defense system in plants. Triggered by double-stranded RNA, silencing results in degradation or translational repression of target transcripts. Viruses are inducers and targets of RNA silencing. To condition susceptibility, most plant viruses encode silencing suppressors that interfere with this process, such as the Tomato spotted wilt virus (TSWV) NSs protein. The mechanism by which NSs suppresses RNA silencing and its role in viral infection and movement remain to be determined. We cloned NSs from the Hawaii isolate of TSWV and using two independent assays show for the first time that this protein restored pathogenicity and supported the formation of local infection foci by suppressor-deficient Turnip mosaic virus and Turnip crinkle virus. Demonstrating the suppression of RNA silencing directed against heterologous viruses establishes the foundation to determine the means used by NSs to block this antiviral process.

Efecto anzuelo en análisis por radioligando del Anti Ácido Glutámico Descarboxilasa (Anti-GAD65). Influencia de la temperatura e interpretación fisicoquímica / Hook effect in radioligand assay for Anti Glutamic Acid Decarboxylase (Anti-GAD65). Influence of temperature and physicochemical interpretation

Objetivo: El análisis por radioligando es uno de los métodos principales utilizados en ladeterminación analítica del Anti-GAD65. Se ha estudiado la influencia de la temperaturasobre las gráficas de calibración obtenidas por dicha técnica.Material y Métodos: Usamos un kit comercial para Anti-GAD65 y un contador gamma. Losresultados son analizados mediante el programa Statistica.Resultados y Discusión: Las actividades ligadas al anticuerpo aumentan con la temperatura.Se observa una disminución de la actividad para altas concentraciones atribuible al llamado“efecto anzuelo”. Se propone un sencillo modelo fisicoquímico que justificasatisfactoriamente los resultados(AU)

Background: Radioligand assay is one of the principal methods used for analyticaldetermination of the Anti-GAD65 concentration. We studied the influence of temperature onthe calibration curves obtained by such a methodMatherial and Methods: We used a commercially available RIA kit for Anti-GAD65 and agamma counter. Data was analyzed using Statistica software.Results and Discusion: Activities bound to the antibody increase with temperature. Therewas a decrease in activity for high concentrations attributable to the "hook effect". Wepropose a simple physicochemical model that justifies satisfactorily the results(AU)

[Distribution of the antigen of hepatitis B virus in liver tissue in healthy carriers and in patients with chronic active and acute hepatitis]. / Distribución del antígeno del virus de la hepatitis B en tejido hepático, en portadores sanos y en pacientes con hepatitis crónica activa y aguda.

We have studied 120 cases of B hepatitis. Sixty were healthy carriers of B virus, 40 had chronic active hepatitis (CAH) and 20 acute hepatitis (AH). The AgsHBV distribution was made in liver tissue by immunoperoxidase technic. In 73% of patients with CAH the AgsHBV was found around portal tracts. In contrast in patients with AH the AgsHBV was seen around central vein. Healthy carriers showed an disseminated pattern. All healthy carrier had AgSHBV in liver, in contrast only 65% of patients with CAH and 20% with AH exhibited AgSHBV in liver biopsy.