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Vaishali Kakkar, E F Elsiena Kuiper, Abhinav Pandey, Ineke Braakman, Harm H Kampinga
Parkinson's disease is one of the most common neurodegenerative disorders and several mutations in different genes have been identified to contribute to the disease. A loss of function parkin RING1 domain mutant (C289G) is associated with autosomal-recessive juvenile-onset Parkinsonism (AR-JP) and displays altered solubility and sequesters into aggregates. Single overexpression of almost each individual member of the Hsp40 (DNAJ) family of chaperones efficiently reduces parkin C289G aggregation and requires interaction with and activity of endogenously expressed Hsp70 s...
October 7, 2016: Scientific Reports
Yonghe Ding, Pamela A Long, J Martijn Bos, Yu-Huan Shih, Xiao Ma, Rhianna S Sundsbak, Jianhua Chen, Yiwen Jiang, Liqun Zhao, Xinyang Hu, Jianan Wang, Yongyong Shi, Michael J Ackerman, Xueying Lin, Stephen C Ekker, Margaret M Redfield, Timothy M Olson, Xiaolei Xu
Mutagenesis screening is a powerful forward genetic approach that has been successfully applied in lower-model organisms to discover genetic factors for biological processes. This phenotype-based approach has yet to be established in vertebrates for probing major human diseases, largely because of the complexity of colony management. Herein, we report a rapid strategy for identifying genetic modifiers of cardiomyopathy (CM). Based on the application of doxorubicin stress to zebrafish insertional cardiac (ZIC) mutants, we identified 4 candidate CM-modifying genes, of which 3 have been linked previously to CM...
September 8, 2016: JCI Insight
Feng Yang, Tai-Yen Chen, Łukasz Krzemiński, Ace George Santiago, Won Jung, Peng Chen
In bacteria, trigger factor (TF) is the molecular chaperone that interacts with the ribosome to assist the folding of nascent polypeptides. Studies in vitro have provided insights into the function and mechanism of TF. Much is to be elucidated, however, about how TF functions in vivo. Here we use single-molecule tracking, in combination with genetic manipulations, to study the dynamics and function of TF in living E. coli cells. We find that TF, besides interacting with the 70S ribosome, may also bind to ribosomal subunits and form TF-polypeptide complexes that may include DnaK/DnaJ proteins...
September 14, 2016: Molecular Microbiology
Rui Yang, Qingyun Bai, Jiaqi Zhang, Yuchen Sheng, Lili Ji
MicroRNA (miRNA) has been reported to play important roles in regulating drug-induced liver injury. Ethyl acetate extract isolated from rhizoma Dioscoreae bulbifera (EF) has been reported to induce hepatotoxicity in our previous studies. This study aims to observe the altered liver miRNA profile and its related signalling pathway involved in EF-induced hepatotoxicity. Serum alanine/aspartate aminotransferase assay showed that EF (450 mg/kg)-induced hepatotoxicity in mice. Results of miRNA chip analysis showed that the expression of eight miRNAs was up-regulated and of other nine miRNAs was down-regulated in livers from EF-treated mice...
September 7, 2016: Human & Experimental Toxicology
Jung Wook Kim, Hyun-Kyung Kim, Gi Su Kang, Il-Hwan Kim, Hwa Su Kim, Yeong Seon Lee, Jae Il Yoo
BACKGROUND: Bacterial two-component regulatory systems (TCRS) are associated with the expression of virulence factors and antibiotic susceptibility. In Staphylococcus aureus, 16 TCRS types have been identified. The histidine kinase/response regulator SAV1321/SAV1322 in the S. aureus shares considerable homology with the TCRS DesKR in Bacillus subtilis. However, a function for the SAV1322 locus has not yet been assigned. RESULTS: Deletion of the SAV1322 locus in S...
2016: BMC Microbiology
Yingying Wu, Jingjing Cui, Xuemei Zhang, Song Gao, Feng Ma, Hua Yao, Xiaoyu Sun, Yujuan He, Yibing Yin, Wenchun Xu
Pneumococcal DnaJ was recently shown to be a potential protein vaccine antigen that induces strong Th1 and Th17 immune response against streptococcus pneumoniae infection in mice. However, how DnaJ mediates T cell immune response against S. pneumoniae infection has not been addressed. Here, we investigate whether DnaJ contributes to the development of T cell immunity through the activation of bone marrow-derived dendritic cells (BMDCs). We found that endotoxin-free recombinant DnaJ (rDnaJ) induced activation and maturation of BMDCs via recognition of Toll-like receptor 4 (TLR4) and activation of MAPKs, NF-κB and PI3K-Akt pathways...
August 31, 2016: Immunobiology
Julia Behnke, Melissa J Mann, Fei-Lin Scruggs, Matthias J Feige, Linda M Hendershot
Protein maturation in the endoplasmic reticulum is controlled by multiple chaperones, but how they recognize and determine the fate of their clients remains unclear. We developed an in vivo peptide library covering substrates of the ER Hsp70 system: BiP, Grp170, and three of BiP's DnaJ-family co-factors (ERdj3, ERdj4, and ERdj5). In vivo binding studies revealed that sites for pro-folding chaperones BiP and ERdj3 were frequent and dispersed throughout the clients, whereas Grp170, ERdj4, and ERdj5 specifically recognized a distinct type of rarer sequence with a high predicted aggregation potential...
September 1, 2016: Molecular Cell
Jie Wang, Sheng-Hua Ying, Yue Hu, Ming-Guang Feng
Mdj1 is a member of the Hsp40 family containing a DnaJ or J domain. Here, we have examined the functions of an Mdj1 orthologue (56.68 kDa) in Beauveria bassiana, a filamentous fungal insect pathogen widely applied in biological control of insect pests. Deletion of mdj1 in B. bassiana resulted in significant growth defects on a variety of complex and minimal media. The Δmdj1 mutant exhibited not only a drastic reduction (92 %) in aerial conidiation during optimal cultivation but also a remarkable decrease (77 %) in submerged blastospore production...
August 11, 2016: Applied Microbiology and Biotechnology
Pryank Patel, Gerald R Prescott, Robert D Burgoyne, Lu-Yun Lian, Alan Morgan
Cysteine string protein (CSP) is a member of the DnaJ/Hsp40 chaperone family that localizes to neuronal synaptic vesicles. Impaired CSP function leads to neurodegeneration in humans and model organisms as a result of misfolding of client proteins involved in neurotransmission. Mammalian CSP is phosphorylated in vivo on Ser10, and this modulates its protein interactions and effects on neurotransmitter release. However, there are no data on the structural consequences of CSP phosphorylation to explain these functional effects...
August 2, 2016: Structure
Elena Sanchez, Hossein Darvish, Roxana Mesias, Shaghyegh Taghavi, Saghar Ghasemi Firouzabadi, Ruth H Walker, Abbas Tafakhori, Coro Paisán-Ruiz
In this study, we described the identification of a large DNAJB2 (HSJ1) deletion in a family with recessive spinal muscular atrophy and Parkinsonism. After performing homozygosity mapping and whole genome sequencing, we identified a 3.8 kb deletion, spanning the entire DnaJ domain of the HSJ1 protein, as the disease-segregating mutation. By performing functional assays, we showed that HSJ1b-related DnaJ domain deletion leads to loss of HSJ1b mRNA and protein levels, increased HSJ1a mRNA and protein expressions, increased cell death, protein aggregation, and enhanced autophagy...
November 2016: Human Mutation
Xinyao Lu, Shuying He, Hong Zong, Jian Song, Wen Chen, Bin Zhuge
1, 2, 4-Butanetriol (BT) is a high-value non-natural chemical and has important applications in polymers, medical production and military industry. In the constructed BT biosynthesis pathway from xylose in Escherichia coli, the xylose dehydrogenase (Xdh) and the benzoylformate decarboxylase (MdlC) are heterologous enzymes and the activity of MdlC is the key limiting factor for BT production. In this study, six chaperone protein systems were introduced into the engineered E. coli harboring the recombinant BT pathway...
September 2016: World Journal of Microbiology & Biotechnology
Shikha Koul, Vipin Chandra Kalia
Bacteria possessing multiple copies of 16S rRNA (rrs) gene demonstrate high intragenomic heterogeneity. It hinders clear distinction at species level and even leads to overestimation of the bacterial diversity. Fifty completely sequenced genomes belonging to 19 species of Lactobacillus species were found to possess 4-9 copies of rrs each. Multiple sequence alignment of 268 rrs genes from all the 19 species could be classified into 20 groups. Lactobacillus sanfranciscensis TMW 1.1304 was the only species where all the 7 copies of rrs were exactly similar and thus formed a distinct group...
September 2016: Indian Journal of Microbiology
Cam Chau Nguyen, Kentaro Nakaminami, Akihiro Matsui, Shuhei Kobayashi, Yukio Kurihara, Kiminori Toyooka, Maho Tanaka, Motoaki Seki
Stress granules (SGs), which are formed in the plant cytoplasm under stress conditions, are transient dynamic sites (particles) for mRNA storage. SGs are actively involved in protecting mRNAs from degradation. Oligouridylate binding protein 1b (UBP1b) is a component of SGs. The formation of microscopically visible cytoplasmic foci, referred to as UBP1b SG, was induced by heat treatment in UBP1b-overexpressing Arabidopsis plants (UBP1b-ox). A detailed understanding of the function of UBP1b, however, is still not clear...
2016: Frontiers in Plant Science
Cheng Wang, Hong-Mi Cui, Tian-Hong Huang, Tong-Kun Liu, Xi-Lin Hou, Ying Li
Non-heading Chinese cabbage (Brassica rapa ssp. chinensis Makino) is an important vegetable member of Brassica rapa crops. It exhibits a typical sporophytic self-incompatibility (SI) system and is an ideal model plant to explore the mechanism of SI. Gene expression research are frequently used to unravel the complex genetic mechanism and in such studies appropriate reference selection is vital. Validation of reference genes have neither been conducted in Brassica rapa flowers nor in SI trait. In this study, 13 candidate reference genes were selected and examined systematically in 96 non-heading Chinese cabbage flower samples that represent four strategic groups in compatible and self-incompatible lines of non-heading Chinese cabbage...
2016: Frontiers in Plant Science
Laura M Carroll, Teresa M Bergholz, Ian M Hildebrandt, Bradley P Marks
Sublethal heating, which can occur during slow cooking of meat products, is known to induce increased thermal resistance in Salmonella. However, very few studies have addressed the kinetics of this response. Although several recent studies have reported improved thermal inactivation models that include the effect of prior sublethal history on subsequent thermal resistance, none of these models were based on cellular-level responses to sublethal thermal stress. The goal of this study was to determine whether a nonlinear model could accurately portray the response of Salmonella to heat stress induced by prolonged exposure to sublethal temperatures...
July 2016: Journal of Food Protection
Hemanth Tummala, Amanda J Walne, Mike Williams, Nicholas Bockett, Laura Collopy, Shirleny Cardoso, Alicia Ellison, Rob Wynn, Thierry Leblanc, Jude Fitzgibbon, David P Kelsell, David A van Heel, Elspeth Payne, Vincent Plagnol, Inderjeet Dokal, Tom Vulliamy
A substantial number of individuals with bone marrow failure (BMF) present with one or more extra-hematopoietic abnormality. This suggests a constitutional or inherited basis, and yet many of them do not fit the diagnostic criteria of the known BMF syndromes. Through exome sequencing, we have now identified a subgroup of these individuals, defined by germline biallelic mutations in DNAJC21 (DNAJ homolog subfamily C member 21). They present with global BMF, and one individual developed a hematological cancer (acute myeloid leukemia) in childhood...
July 7, 2016: American Journal of Human Genetics
D Stępień-Pyśniak, J Wilczyński, A Marek, A Śmiech, U Kosikowska, T Hauschild
This report suggests a strong association between coagulase-negative Staphylococcus  simulans and endocarditis in broiler chickens of a single flock. Clinical signs included increased mortality and lameness, and some dead chickens were found on their backs. Lesions included cauliflower-like, fibrinous vegetative lesions on the left atrioventricular (AV) valve; cream-coloured, necrotic foci of varying size in the liver, and necrosis of the femoral head. Histopathological examination of the heart revealed multifocal conglomerates of bacterial colonies attached to the valvular endocardium, threads of fibrin, inflammatory cells with the presence of heterophils...
June 22, 2016: Avian Pathology: Journal of the W.V.P.A
Erhong Meng, Lalita A Shevde, Rajeev S Samant
DNAJB6 also known as mammalian relative of DnaJ (MRJ) encodes a highly conserved member of the DnaJ/Hsp40 family of co-chaperone proteins that function with Hsp70 chaperones. DNAJB6 is widely expressed in all tissues, with higher expression levels detected in the brain. DNAJB6 is involved in diverse cellular functions ranging from murine placental development, reducing the formation and toxicity of mis-folded protein aggregates, to self-renewal of neural stem cells. Involvement of DNAJB6 is implicated in multiple pathologies such as Huntington's disease, Parkinson's diseases, limb-girdle muscular dystrophy, cardiomyocyte hypertrophy and cancer...
June 2, 2016: Oncotarget
Sarah N Fontaine, Dali Zheng, Jonathan J Sabbagh, Mackenzie D Martin, Dale Chaput, April Darling, Justin H Trotter, Andrew R Stothert, Bryce A Nordhues, April Lussier, Jeremy Baker, Lindsey Shelton, Mahnoor Kahn, Laura J Blair, Stanley M Stevens, Chad A Dickey
It is now known that proteins associated with neurodegenerative disease can spread throughout the brain in a prionlike manner. However, the mechanisms regulating the trans-synaptic spread propagation, including the neuronal release of these proteins, remain unknown. The interaction of neurodegenerative disease-associated proteins with the molecular chaperone Hsc70 is well known, and we hypothesized that much like disaggregation, refolding, degradation, and even normal function, Hsc70 may dictate the extracellular fate of these proteins...
July 15, 2016: EMBO Journal
Rupa Banerjee, Gopal Gunanathan Jayaraj, Joshua Jebakumar Peter, Vignesh Kumar, Koyeli Mapa
DnaK or Hsp70 of Escherichia coli is a master regulator of the bacterial proteostasis network. Allosteric communication between the two functional domains of DnaK, the N-terminal nucleotide-binding domain (NBD) and the C-terminal substrate- or peptide-binding domain (SBD) regulate its activity. X-ray crystallography and NMR studies have provided snapshots of distinct conformations of Hsp70 proteins in various physiological states; however, the conformational heterogeneity and dynamics of allostery-driven Hsp70 activity remains underexplored...
August 2016: FEBS Journal
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