Read by QxMD icon Read

26S proteasome

Antonia A Nemec, Lauren A Howell, Anna K Peterson, Matthew A Murray, Robert J Tomko
Turnover of the 26S proteasome by autophagy is an evolutionarily conserved process that governs cellular proteolytic capacity and eliminates inactive particles. In most organisms, proteasomes are located in both the nucleus and cytoplasm. However, the specific autophagy routes for nuclear and cytoplasmic proteasomes are unclear. Here, we investigate the spatial control of autophagic proteasome turnover in budding yeast (Saccharomyces cerevisiae). We found that nitrogen starvation-induced proteasome autophagy is independent of known nucleophagy pathways, but is compromised when nuclear protein export is blocked...
November 6, 2017: Journal of Biological Chemistry
Brittany M Johnson, Russell A DeBose-Boyd
Accelerated ubiquitination and subsequent endoplasmic reticulum (ER)-associated degradation (ERAD) constitute one of several mechanisms for feedback control of HMG CoA reductase, the rate-limiting enzyme in synthesis of cholesterol and nonsterol isoprenoids. This ERAD is initiated by the accumulation of certain sterols in ER membranes, which trigger binding of reductase to ER membrane proteins called Insigs. Insig-associated ubiquitin ligases facilitate ubiquitination of reductase, marking the enzyme for extraction across the ER membrane through a reaction that is augmented by nonsterol isoprenoids...
October 28, 2017: Seminars in Cell & Developmental Biology
Charlotte Montacié, Nathalie Durut, Alison Opsomer, Denise Palm, Pascale Comella, Claire Picart, Marie-Christine Carpentier, Frederic Pontvianne, Christine Carapito, Enrico Schleiff, Julio Sáez-Vásquez
In all eukaryotic cells, the nucleolus is functionally and structurally linked to rRNA synthesis and ribosome biogenesis. This compartment contains as well factors involved in other cellular activities, but the functional interconnection between non-ribosomal activities and the nucleolus (structure and function) still remains an open question. Here, we report a novel mass spectrometry analysis of isolated nucleoli from Arabidopsis thaliana plants using the FANoS (Fluorescence Assisted Nucleolus Sorting) strategy...
2017: Frontiers in Plant Science
Ning Zhang, Yujing Yin, Xinye Liu, Shaoming Tong, Jiewen Xing, Yuan Zhang, Ramesh N Pudake, Edenys Miranda Izquierdo, Huiru Peng, Mingming Xin, Zhaorong Hu, Zhongfu Ni, Qixin Sun, Yingyin Yao
In Arabidopsis plants growing under normal conditions, DEHYDRATION-RESPONSIVE ELEMENT BINDING PROTEIN2A (DREB2A) is present at low levels because it is ubiquitinated and destabilized by DREB2A INTERACTING PROTEIN 1 (DRIP1) and DRIP2 through 26S proteasome-mediated proteolysis. Drought stress counteracts the ubiquitination and proteolysis of DREB2A, thus allowing accumulation of sufficient amounts of DREB2A protein to activate downstream gene expression. The mechanisms leading to drought stress-mediated DREB2A accumulation are still unclear...
October 31, 2017: Plant Physiology
Jordan J S VerPlank, Sudarsanareddy Lokireddy, M Laura Feltri, Alfred L Goldberg, Lawrence Wrabetz
In several neurodegenerative diseases in which misfolded proteins accumulate there is impairment of the ubiquitin proteasome system (UPS). We tested if a similar disruption of proteostasis occurs in hereditary peripheral neuropathies. In sciatic nerves from mouse models of two human neuropathies, Myelin Protein Zero mutation (S63del) and increased copy number (P0 overexpression), polyubiquitinated proteins accumulated, and the overall rates of protein degradation were decreased. 26S proteasomes affinity-purified from sciatic nerves of S63del mice were defective in degradation of peptides and a ubiquitinated protein, unlike proteasomes from P0 overexpression, which appeared normal...
October 27, 2017: Glia
Wafik Zaky, Christa Manton, Claudia P Miller, Soumen Khatua, Vidya Gopalakrishnan, Joya Chandra
Nearly 20 years ago, the concept of targeting the proteasome for cancer therapy began gaining momentum. This concept was driven by increased understanding of the biology/structure and function of the 26S proteasome, insight into the role of the proteasome in transformed cells, and the synthesis of pharmacological inhibitors with clinically favorable features. Subsequent in vitro, in vivo, and clinical testing culminated in the FDA approval of three proteasome inhibitors-bortezomib, carfilzomib, and ixazomib -for specific hematological malignancies...
October 25, 2017: Cancer Metastasis Reviews
Chiel C de Theije, Annemie M W J Schols, Wouter H Lamers, Judith J M Ceelen, Rick H van Gorp, J J Rob Hermans, S Elonore Köhler, Ramon C J Langen
Hypoxemia may contribute to muscle wasting in conditions such as Chronic Obstructive Pulmonary Disease. Muscle wasting develops when muscle proteolysis exceeds protein synthesis. Hypoxia induces skeletal muscle atrophy in mice, which can in part be attributed to reduced food intake. We hypothesized that hypoxia elevates circulating corticosterone concentrations by reduced food intake and enhances GR signaling in muscle, which causes elevated protein degradation signaling and dysregulates protein synthesis signaling during hypoxia-induced muscle atrophy...
October 23, 2017: Endocrinology
Marybeth Carmody, Tara P Notarianni, Larissa A Sambel, Shannon J Walsh, Jenna M Burke, Jenna L Armstrong, T Glen Lawson
The encephalomyocarditis virus (EMCV) 3C protease (3C(pro)) is one of a small number of viral proteins whose concentration is known to be regulated by the cellular ubiquitin-proteasome system. Here we report that the ubiquitin-conjugating enzyme UbcH7/UBE2L3 and the ubiquitin-protein ligase E6AP/UBE3A are components of a previously unknown EMCV 3C(pro)-polyubiquitylating pathway. Following the identification of UbcH7/UBE2L3 as a participant in 3C(pro) ubiquitylation, we purified a UbcH7-dependent 3C(pro)-ubiquitylating activity from mouse cells, which we identified as E6AP...
December 9, 2017: Biochemical and Biophysical Research Communications
Jae-Kwang Jung, Gi-Jeong Gwon, Sanjiv Neupane, Wern-Joo Sohn, Ki-Rim Kim, Ji-Youn Kim, Seo-Young An, Tae-Yub Kwon, Chang-Hyeon An, Youngkyun Lee, Jae-Young Kim, Jung-Hong Ha
INTRODUCTION: The aim of this study was to evaluate in vitro and ex vivo roles of bortezomib, a proteasome inhibitor that binds to the active site of the 26S proteasome, in tertiary dentin formation. METHODS: We established pulpal access cavity preparation that was treated with or without bortezomib before direct pulp capping with a calcium hydroxide-based material. We also analyzed bone morphogenetic protein (Bmp)- and Wnt-related signaling molecules using quantitative real-time polymerase chain reaction...
October 9, 2017: Journal of Endodontics
Yanlin Yang, Wenqiang Wang, Tian Xu, Na Liu, Honggang Wang, Deshun Feng
Expression of TaRUB1 gene in Arabidopsis thaliana elevates the level of disease-related genes in response to pathogen invasion through the accumulation of callose, necrotic cells, and the outbreak of ROS. Ubiquitin (Ub) and ubiquitin-like proteins are highly conserved in sequence and can covalently bind and modify many intracellular proteins which can be recognized and degraded by 26S proteasome. Post-translational modification of proteins has become a hot research spot today. In the previous study, a cDNA of related-to-ubiquitin protein belonged to ubiquitin-like proteins, whose spatial structure comprised Ub and NEDD8, was obtained from wheat SN6306 by suppression-subtractive hybridization and was named TaRUB1...
December 2017: Plant Cell Reports
Blaine Bartholomew
In addition to its proteolytic roles, the 26S proteasome is involved in regulating transcription and in promoting sites of active chromatin. In this report, Seo et al. provide evidence that the non-proteolytic 19S subunit of the 26S proteasome also regulates the spreading of inactive chromatin referred to as heterochromatin, suggesting further non-canonical roles of the proteasome in gene expression.
October 13, 2017: Journal of Biological Chemistry
Jannatul Ferdoush, Saswati Karmakar, Priyanka Barman, Amala Kaja, Bhawana Uprety, Surinder K Batra, Sukesh R Bhaumik
The evolutionarily conserved RNA polymerase II-associated factor 1 (Paf1) from yeast to humans regulates transcription and associated processes, and thus, malfunctions and/or misregulations of Paf1 are associated with cellular pathologies. Indeed, Paf1 (also known as PD2 or pancreatic differentiation 2) is found to be upregulated in poorly differentiated cancer cells, and such upregulation is involved in cellular transformation or oncogenesis. However, the basis for Paf1 upregulation in these cells remains largely unknown...
October 19, 2017: Biochemistry
Susheng Song, Jiaojiao Wang, Bei Liu, Tiancong Qi, Daoxin Xie
Jasmonates (JAs), lipid-derived phytohormones, regulate plant growth, development and defenses against biotic stresses. CORONATINE INSENSITIVE1 perceives bioactive JA and recruits JASMONATE ZIM-DOMAIN (JAZ) proteins for ubiquitination and subsequent degradation via the 26S proteasome, which de-represses JAZ-targeted transcription factors that regulate diverse JA responses. Recent studies showed that the Arabidopsis basic helix-loop-helix transcription factor MYC5 interacts with JAZs and regulates stamen development...
August 10, 2017: Plant & Cell Physiology
Jian-Ping An, Xin Liu, Hao-Hao Li, Chun-Xiang You, Xiao-Fei Wang, Yu-Jin Hao
MdMYB1 is an important regulator for anthocyanin accumulation in apple (Malus × domestica). Here, an apple RING E3 ligase, MdMIEL1, was screened out as a partner of MdMYB1 with a yeast two-hybrid approach. Pull-down, bimolecular fluorescence complementation and coimmunoprecipitation assays further verified the interaction between MdMIEL1 and MdMYB1 proteins. Subsequently, in vitro and in vivo experiments indicated that MdMIEL1 functioned as a ubiquitin E3 ligase to ubiquitinate MdMYB1 protein, followed by degradation through a 26S proteasome pathway...
November 1, 2017: Plant & Cell Physiology
Toshiyuki Okumura, Kazuhiro Ikeda, Takafumi Ujihira, Koji Okamoto, Kuniko Horie-Inoue, Satoru Takeda, Satoshi Inoue
Endocrine therapy using antiestrogens and aromatase inhibitors is usually efficient to treat patients with hormone-sensitive breast cancer. Many patients with endocrine therapy, however, often acquire resistance. In the present study, we performed functional screening using short hairpin RNA library to dissect genes involved in antiestrogen tamoxifen resistance in MCF-7 breast cancer cells. We identified seven candidate genes that are associated with poor prognosis of breast cancer patients based on clinical dataset...
August 3, 2017: Journal of Biochemistry
Haiou Li, Ruifeng Yao, Sui Ma, Shuai Hu, Suhua Li, Yupei Wang, Chun Yan, Daoxin Xie, Jianbin Yan
Ubiquitin-mediated protein degradation plays an essential role in plant growth and development as well as responses to environmental and endogenous signals. F-box protein is one of the key components of the SCF (SKP1-CUL1-F-box protein) E3 ubiquitin ligase complex, which recruit specific substrate proteins for subsequent ubiquitination and 26S proteasome-mediated degradation to regulate developmental processes and signaling networks. However, it is not easy to obtain purified F-box proteins with high activity due to their unstable protein structures...
September 5, 2017: Plant Journal: for Cell and Molecular Biology
Chunhua Han, Ran Zhao, John Kroger, Jinshan He, Gulzar Wani, Qi-En Wang, Altaf A Wani
Subunit 2 of DNA damage-binding protein complex (DDB2) is an early sensor of nucleotide excision repair (NER) pathway for eliminating DNA damage induced by UV radiation (UVR) and cisplatin treatments of mammalian cells. DDB2 is modified by ubiquitin and poly(ADP-ribose) (PAR) in response to UVR, and these modifications play a crucial role in regulating NER. Here, using immuno-analysis of irradiated cell extracts, we have identified multiple post-irradiation modifications of DDB2 protein. Interestingly, although the DNA lesions induced by both UVR and cisplatin are corrected by NER, only the UV irradiation, but not the cisplatin treatment, induces any discernable DDB2 modifications...
October 1, 2017: Carcinogenesis
Jordan J S VerPlank, Alfred L Goldberg
The ubiquitin proteasome system degrades the great majority of proteins in mammalian cells. Countless studies have described how ubiquitination promotes the selective degradation of different cell proteins. However, there is a small but the growing literature that protein half-lives can also be regulated by post-translational modifications of the 26S proteasome. The present study reviews the ability of several kinases to alter proteasome function through subunit phosphorylation. For example, PKA (protein kinase A) and DYRK2 (dual-specificity tyrosine-regulated kinase 2) stimulate the proteasome's ability to degrade ubiquitinated proteins, peptides, and adenosine triphosphate, while one kinase, ASK1 (apoptosis signal-regulating kinase 1), inhibits proteasome function during apoptosis...
September 24, 2017: Biochemical Journal
Lisa Zondler, Marcus Kostka, Patrick Garidel, Udo Heinzelmann, Bastian Hengerer, Benjamin Mayer, Jochen H Weishaupt, Frank Gillardon, Karin M Danzer
Parkinson's disease (PD) is the second most prevalent neurodegenerative disorder worldwide and characterized by the loss of dopaminergic neurons in the patients' midbrains. Both the presence of the protein α-synuclein in intracellular protein aggregates in surviving neurons and the genetic linking of the α-synuclein encoding gene point towards a major role of α-synuclein in PD etiology. The exact pathogenic mechanisms of PD development are not entirely described to date, neither is the specific role of α-synuclein in this context...
2017: PloS One
M Osman Sheikh, David Thieker, Gordon Chalmers, Christopher M Schafer, Mayumi Ishihara, Parastoo Azadi, Robert J Woods, John N Glushka, Brad Bendiak, James H Prestegard, Christopher M West
Skp1 is a conserved protein linking cullin-1 to F-box proteins in SCF (Skp1-Cullin1-F-box) E3 ubiquitin ligases, which modify protein substrates with polyubiquitin chains that typically target them for 26S proteasome-mediated degradation. In Dictyostelium (a social amoeba), Toxoplasma gondii (the agent for human toxoplasmosis), and other protists, Skp1 is regulated by a unique pentasaccharide attached to hydroxylated Pro-143 within its C-terminal F-box binding domain. Prolyl hydroxylation of Skp1 contributes to O2-dependent Dictyostelium development, but full glycosylation at that position is required for optimal O2 sensing...
September 19, 2017: Journal of Biological Chemistry
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"