La proteína tuberina: diana terapéutica para activar autofagia y mitofagia evitando la progresión a la diabetes tipo 2 / Tuberin protein: therapeutic target to activate autophagy and mitophagy avoiding the progression to type 2 diabetes

El control de calidad citoplasmático es esencial en el mantenimiento de la viabilidad celular, y particularmente, de las células β pancreáticas, debido a su gran capacidad de síntesis proteica. En este contexto, juega un papel esencial la activación de un proceso fisiológico denominado autofagia, conduciendo a la eliminación de agregados proteicos y/o orgánulos, induciendo la atenuación del estrés de retículo celular. El complejo formado por las proteínas hamartina y tuberina (TSC1-TSC2) ha emergido como un núcleo de integración de la señalización de factores de crecimiento y del estado energético celular. Este complejo funciona como un inhibidor de la actividad de la vía del complejo mecanicístico diana de la rapamicina (mTORC1) y un activador de la autofagia. En este proyecto queremos profundizar en el estudio de nuevos mecanismos moleculares de regulación de TSC2, así como sobre dichos mecanismos de control de calidad citoplasmático, autofagia y mitofagia. Proponemos que el estado de acetilación en lisinas de TSC2, mediado por la actividad desacetilasa de la sirtuina1 (SIRT1), modula la estabilidad y actividad de la misma afectando a la homeostasis celular (AU)

Cytoplasmic quality control is essential in maintaining cell viability, and articularly, β pancreatic cells, due to its huge protein synthesis capacity. In this context, it is important the activation of a physiological process called autophagy, in order to eliminate protein aggregates and damaged organelles, resulting in a reduction in the reticulum cell stress. The complex formed by hamartin and tuberin (TSC1-TSC2) has emerged as a central signal, energy status and nutrient-integrating node within the cell. This complex negatively regulates the mechanistic target of rapamycin complex 1 (mTORC1), and activates autophagy. In this proyect we aimed to further investigate new molecular mechanisms of TSC2 regulation, aswell as cytoplasmic quality control, autophagy and mitophagy ones. We propose that the TSC2 acetylation status, mediated by the deacetylation activity of sirtuin1 (SIRT1), modulates its stability and protein activity, affecting cell homeostasis

Protein complex immunological separation assay (ProCISA): a technique for investigating single protein properties

Analysis of the posttranslational modification of proteins, such as phosphorylation,might yield misleading results due to the presence of other proteins with similar electrophoreticproperties that coimmunoprecipitate with the target protein. The aim ofthe present work was to develop a reliable, easy and economical technique to completelyisolate a protein from its complex. Here we present a new assay developed tofully isolate proteins from macromolecular complexes that consists of an initialSDS/PAGE (under reducing conditions), which isolates the target protein, followedby transfer of the proteins to a buffer, from which the target protein is recaptured byconventional immunoprecipitation. This technique, that we have termed “ProteinComplex Immunological Separation Assay” (ProCISA), successfully separated proteinsof different sizes, such as pp60Src and the IP3 receptor (IP3R), from their complexes.We show that ProCISA allows the investigation of the tyrosine phosphorylationstate of isolated proteins. This technique could also be used to study other posttranslationalmodifications without risk of misleading results resulting from contaminationwith other proteins of similar electrophoretic mobility which complex with theprotein of interest (AU)

No disponible