Search results for "molecular chaperone"

DICER and ZRF1 contribute to chromatin decondensation during nucleotide excision repair

2016

Abstract Repair of damaged DNA relies on the recruitment of DNA repair factors in a well orchestrated manner. As a prerequisite, the chromatin needs to be decondensed by chromatin remodelers to allow for binding of repair factors and for DNA repair to occur. Recent studies have implicated members of the SWI/SNF and INO80 families as well as PARP1 in nucleotide excision repair (NER). In this study, we report that the endonuclease DICER is implicated in chromatin decondensation during NER. In response to UV irradiation, DICER is recruited to chromatin in a ZRF1-mediated manner. The H2A–ubiquitin binding protein ZRF1 and DICER together impact on the chromatin conformation via PARP1. Moreover, …

A transmembrane serine residue in the Rot1 protein is essential for yeast cell viability

2014

Polar residues are present in TM (transmembrane) helices and may influence the folding or association of membrane proteins. In the present study, we use an in vivo approach to analyse the functional and structural roles for amino acids in membrane-spanning motifs using the Rot1 (reversal of Tor2 lethality 1) protein as a model. Rot1 is an essential membrane protein in Saccharomyces cerevisiae and it contains a single TM domain. An alanine insertion scanning analysis of this TM helix revealed that the integrity of the central domain is essential for protein function. We identified a critical serine residue inside the helix that plays an essential role in maintaining cell viability in S. cere…

Rot1 plays an antagonistic role to Clb2 in actin cytoskeleton dynamics throughout the cell cycle.

2007

ROT1 is an essential gene whose inactivation causes defects in cell cycle progression and morphogenesis in budding yeast. Rot1 affects the actin cytoskeleton during the cell cycle at two levels. First, it is required for the maintenance of apical growth during bud growth. Second, Rot1 is necessary to polarize actin cytoskeleton to the neck region at the end of mitosis; because of this defect, rot1 cells do not properly form a septum to complete cell division. The inability to polarize the actin cytoskeleton at the end of mitosis is not due to a defect in the recruitment of the polarisome scaffold protein Spa2 or the actin cytoskeleton regulators Cdc42 and Cdc24 in the neck region. Previous …

Unveiling novel interactions of histone chaperone Asf1 linked to TREX-2 factors Sus1 and Thp1

2014

13 páginas, 7 figuras, 2 yablas

Overexpression of apolipoprotein J in human fibroblasts protects against cytotoxicity and premature senescence induced by ethanol and tert-butylhydro…

2008

Human diploid fibroblasts (HDFs) exposed to subcytotoxic stresses under H2O2, tert-butylhydroperoxide (t-BHP), and ethanol (EtOH) undergo stress-induced premature senescence (SIPS) characterized by many biomarkers of HDFs replicative senescence. Among these biomarkers are a growth arrest, an increase in the senescence-associated β-galactosidase activity, a senescent morphology, an overexpression of p21waf-1 and the subsequent inability to phosphorylate pRb, the presence of the common 4977-bp mitochondrial deletion, and an increase in the steady-state level of several senescence-associated genes such as apolipoprotein J (apo J). Apo J has been described as a survival gene against cytotoxic s…

The Chaperone System in Breast Cancer: Roles and Therapeutic Prospects of the Molecular Chaperones Hsp27, Hsp60, Hsp70, and Hsp90

2022

Breast cancer (BC) is a major public health problem, with key pieces of information needed for developing preventive and curative measures still missing. For example, the participation of the chaperone system (CS) in carcinogenesis and anti-cancer responses is poorly understood, although it can be predicted to be a crucial factor in these mechanisms. The chief components of the CS are the molecular chaperones, and here we discuss four of them, Hsp27, Hsp60, Hsp70, and Hsp90, focusing on their pro-carcinogenic roles in BC and potential for developing anti-BC therapies. These chaperones can be targets of negative chaperonotherapy, namely the elimination/blocking/inhibition of the chaperone(s)…

EXPRESSION AND LOCALIZATION OF “CHAPEROKINE” HSP60 IN BRONCHIAL CULTURE MODELS MIMING COPD

The Chaperone System in Salivary Glands: Hsp90 Prospects for Differential Diagnosis and Treatment of Malignant Tumors

2022

Salivary gland tumors represent a serious medical problem and new tools for differential diagnosis and patient monitoring are needed. Here, we present data and discuss the potential of molecular chaperones as biomarkers and therapeutic targets, focusing on Hsp10 and Hsp90. The salivary glands are key physiological elements but, unfortunately, the information and the means available for the management of their pathologies, including cancer, are scarce. Progress in the study of carcinogenesis has occurred on various fronts lately, one of which has been the identification of the chaperone system (CS) as a physiological system with presence in all cells and tissues (including the salivary gland…

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 [1,2]. Since exosomes are released into body fluids, they may be used in nanomedicine as a valuable source of diagnostic biomarkers [3]. 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 d…

Hsp27 and Hsp60 in human submandibular salivary gland: Quantitative patterns in healthy and cancerous tissues with potential implications for differe…

2021

Tumors of the submandibular salivary gland (SMG) are uncommon but sufficiently frequent for the physician to consider them in routine examinations and for the pathologist to be prepared to differentiate them from other tissue abnormalities. However, scarcity of specimens makes training difficult, a situation compounded by the lack of accepted universal diagnostic guidelines. Furthermore, there is little information on the chaperone system (CS) of the gland, despite the increasing evidence of its participation in carcinogenesis as a biomarker for diagnosis and patient follow up, and in the mechanisms by which the tumor cells thrive. We are investigating this aspect of various tumors, and her…