Search results for "CHAPERONE"

Stability and disassembly properties of human naïve Hsp60 and bacterial GroEL chaperonins.

2015

Human Hsp60 chaperonin and its bacterial homolog GroEL, in association with the corresponding co-chaperonins Hsp10 and GroES, constitute important chaperone systems promoting the proper folding of several mitochondrial proteins. Hsp60 is also currently described as a ubiquitous molecule with multiple roles both in health conditions and in several diseases. Naïve Hsp60 bearing the mitochondrial import signal has been recently demonstrated to present different oligomeric organizations with respect to GroEL, suggesting new possible physiological functions. Here we present a combined investigation with circular dichroism and small-angle X-ray scattering of structure, self-organization, and sta…

Molecular Pathways Implicated in Radioresistance of Glioblastoma Multiforme: What Is the Role of Extracellular Vesicles?

2023

Glioblastoma multiforme (GBM) is a primary brain tumor that is very aggressive, resistant to treatment, and characterized by a high degree of anaplasia and proliferation. Routine treatment includes ablative surgery, chemotherapy, and radiotherapy. However, GMB rapidly relapses and develops radioresistance. Here, we briefly review the mechanisms underpinning radioresistance and discuss research to stop it and install anti-tumor defenses. Factors that participate in radioresistance are varied and include stem cells, tumor heterogeneity, tumor microenvironment, hypoxia, metabolic reprogramming, the chaperone system, non-coding RNAs, DNA repair, and extracellular vesicles (EVs). We direct our a…

ROLE OF HEME OXYGENASE-1 (HSP32) AND HSP90 IN GLIOBLASTOMA

2017

Glioblastoma (GBM) is the most common and malignant primary brain tumor in adults. The current treatment regimes for glioblastoma demonstrated a low efficiency and offer a poor prognosis. Advancements in conventional treatment strategies have only yielded modest improvements in overall survival. The heat shockproteins, heme oxygenase-1 (HO-1) and Hsp90, serve these pivotal roles in tumor cells and have been identified as effective targets for developing therapeutics. This topic review summarizes the current preclinical and clinical evidences and rationale to define the potential of HO-1 and Hsp90 in GBM progression and chemoresistance.

Hsp60 in Skeletal Muscle: From Molecular Anatomy to Pathophysiology

2019

The chaperoning system of an organism is composed of the entire set of chaperones, co-chaperones, and chaperone co-factors and their interactors and receptors. Its functions pertain typically to protein homeostasis but also to many other activities inside and outside cells. In the skeletal muscle, with its multi-molecular structures rich in proteins and their continuous rearrangements, the chaperoning system plays a crucial role. However, little is known about the details of the workings of the chaperoning system in skeletal muscle development and during exercise and disease. Molecular chaperones are surely involved in muscle formation and maintenance under physiologic conditions and under …

Exosomal HSP60 levels and related miRNAs in brain tumors

In cancer, Extracellular Vesicles (EVs), such as exosomes, contribute to tumor progression by regulating local and systemic parameters. Since exosomes are released into body fluids, they may be used in nanomedicine as a valuable source of diagnostic biomarkers. The prognosis of brain tumors is poor even after surgical resection followed by post-operatory chemo- and radio-therapies and it is cogent to find innovative treatments. The discovery that molecular chaperones can be determinant factors in tumorigenesis and the increasing understanding of exosomes, particularly in what refers to their release by tumor cells and contents, including chaperones and miRNA, provide elements to develop nov…

The molecular anatomy of human Hsp60 and its effects on Amyloid-β peptide

Heat Shock Protein 60 (HSP60) is ubiquitous and highly conserved, being present in eukaryotes and prokaryotes, including pathogens. This chaperonin is typically considered a mitochondrial protein but it is also found in other intracellular sites, extracellularly and in circulation. HSP60 is an indispensable component of the Chaperoning System and plays a key role in protein quality control, preventing off-pathway folding events and refolding misfolded proteins. This makes HSP60 a putative therapeutic agent for neurodegenerative diseases associated with aggregation of misfolded proteins, for example, Alzheimer’s Disease. We produced and purified recombinant human HSP60 and investigated the e…

Heat Shock Protein 60 in Hepatocellular Carcinoma: Insights and Perspectives

2020

Heat shock protein 60 (HSP60) is a mitochondrial chaperone that is implicated in physiological and pathological processes. For instance, it contributes to protein folding and stability, translocation of mitochondrial proteins, and apoptosis. Variations in the expression levels of HSP60 have been correlated to various diseases and cancers, including hepatocellular carcinoma (HCC). Unlike other HSPs which clearly increase in some cancers, data about HSP60 levels in HCC are controversial and difficult to interpret. In the current review, we summarize and simplify the current knowledge about the role of HSP60 in HCC. In addition, we highlight the possibility of its targeting, using chemical com…

THE CHAPERONE SYSTEM IN SALIVARY GLAND DEVELOPMENT

2023

The chaperone system (CS) canonical function is to maintain protein homeostasis. Proper folding of nascent peptides is crucial in developing tissue. The chief components of the CS are 95th National Congress of the Italian Society for Experimental Biology | Trieste, Italy, 12-15 April 2023Non-commercial use only the molecular chaperones, which play key roles in development as indicated by their presence in embryonic tissue as early as at two-cell stage. However, scarce information on the CS in developing tissues is available, especially at advanced stages of embryogenesis and its role is not fully understood. In our previous study, we reported the presence of molecular chaperones in the duct…

Nuclear localization but not PML protein is required for incorporation of the papillomavirus minor capsid protein L2 into virus-like particles.

2004

ABSTRACT Recent reports suggest that nuclear domain(s) 10 (ND10) is the site of papillomavirus morphogenesis. The viral genome replicates in or close to ND10. In addition, the minor capsid protein, L2, accumulates in these subnuclear structures and recruits the major capsid protein, L1. We have now used cell lines deficient for promyelocytic leukemia (PML) protein, the main structural component of ND10, to study the role of this nuclear protein for L2 incorporation into virus-like particles (VLPs). L2 expressed in PML protein knockout (PML −/− ) cells accumulated in nuclear dots, which resemble L2 aggregates forming at ND10 in PML protein-containing cells. These L2 assemblies also attracted…