Search results for "subcellular localization"

Cellular complexity in MAPK signaling in plants: Questions and emerging tools to answer them

2018

International audience; Mitogen activated protein kinase (MAPK) cascades play an important role in many aspects of plant growth, development, and environmental response. Because of their central role in many important processes, MAPKs have been extensively studied using biochemical and genetic approaches. This work has allowed for the identification of the MAPK genes and proteins involved in a number of different signaling pathways. Less well developed, however, is our understanding of how MAPK cascades and their corresponding signaling pathways are organized at subcellular levels. In this review, we will provide an overview of plant MAPK signaling, including a discussion of what is known a…

Nuclear signaling of plant MAPKs

2018

This article is part of the research topic: Post-Translational Modifications in Plant Nuclear Signaling: Novel Insights into Responses to Environmental Changes; International audience; Mitogen-activated protein kinases (MAPKs) are conserved protein kinases in eukaryotes that establish signaling modules where MAPK kinase kinases (MAPKKKs) activate MAPK kinases (MAPKKs) which in turn activate MAPKs. In plants, they are involved in the signaling of multiple environmental stresses and developmental programs. MAPKs phosphorylate their substrates and this post-translational modification (PTM) contributes to the regulation of proteins. PTMs may indeed modify the activity, subcellular localization,…

Differential subcellular localization of endogenous and transfected soluble epoxide hydrolase in mammalian cells: evidence for isozyme variants

1999

AbstractEndogenous, constitutive soluble epoxide hydrolase in mice 3T3 cells was localized via immunofluorescence microscopy exclusively in peroxisomes, whereas transiently expressed mouse soluble epoxide hydrolase (from clofibrate-treated liver) accumulated only in the cytosol of 3T3 and HeLa cells. When the C-terminal Ile of mouse soluble epoxide hydrolase was mutated to generate a prototypic putative type 1 PTS (-SKI to -SKL), the enzyme targeted to peroxisomes. The possibility that soluble epoxide hydrolase-SKI was sorted slowly to peroxiosmes from the cytosol was examined by stably expressing rat soluble epoxide hydrolase-SKI appended to the green fluorescent protein. Green fluorescent…

2013

Clusterin, also known as apolipoprotein J, is expressed from a variety of tissues and implicated in pathological disorders such as neurodegenerative diseases, ischemia and cancer. In contrast to secretory clusterin (sCLU), which acts as an extracellular chaperone, the synthesis, subcellular localization and function(s) of intracellular CLU isoforms is currently a matter of intense discussion. By investigating human CLU mRNAs we here unravel mechanisms leading to the synthesis of distinct CLU protein isoforms and analyze their subcellular localization and their impact on apoptosis and on NF-κB-activity. Quantitative PCR-analyses revealed the expression of four different stress-inducible CLU …

Localization of the two constitutively expressed nitric oxide synthase isoforms (nNOS and eNOS) in the same cell types in the saccule maculae of the …

2003

There is growing evidence for a nitric oxide/cyclic GMP pathway of signal transduction in the vestibular system. Recently, two isoforms of nitric oxide (NO) synthase (nNOS and eNOS) and NO itself have been identified at the light microscopic level in the vestibulocochlear system of mice using specific antibodies and a new fluorescence indicator. In order to acquire more information about signal transduction and tissue modulation in this neuroepithelium at the cellular and subcellular levels, ultrathin sections of London Resin White-embedded saccule maculae of the frog Rana pipiens were incubated with various concentrations of commercially available antibodies to nNOS and eNOS. The immunorea…

Subcellular localization of pentachlorophenol 4-monooxygenase in Sphingobium chlorophenolicum ATCC 39723.

2002

Abstract We have studied the subcellular localization of pentachlorophenol 4-monooxygenase (PCP4MO) in Sphingobium chlorophenolicum ATCC 39723 during induction by pentachlorophenol (PCP). Using a monoclonal antibody CL6 specific to the native and recombinant PCP4MO, the enzyme was primarily found soluble as determined by immunoblot and ELISA analyses of cellular fractions. However, the enzyme was observed both in the soluble and membrane-bound forms during induction for 2–4 h, suggesting its translocation out from the cytoplasm. Electron microscopy confirmed that PCP4MO was predominantly present in the cytoplasm at 1 h, whereas at 4 h significant amount was detected also in the membrane and…

GFP immunogold staining, from light to electron microscopy, in mammalian cells.

2012

GFP has emerged as an important reporter for monitoring gene expression, protein localization, cell transformation and cell lineage. The development of GFP as a marker in many different biological systems has emphasized the need to image GFP at high resolution. GFP immunogold labeling with colloidal gold particles becomes essential for electron microscopy (EM) ultrastructural detection. Because of the small size, colloidal gold particles require silver enhancement, a procedure to increase the size of the particle as well as gold toning to stabilize the silver layer. GFP preembedding immunogold staining enables high quality cellular-ultrastructural EM analysis mainly for two reasons, on one …

Reticulon-like proteins in Arabidopsis thaliana: structural organization and ER localization

2007

International audience; Reticulons are proteins that have been found predominantly associated with the endoplasmic reticulum in yeast and mammalian cells. While their functions are still poorly understood, recent findings suggest that they participate in the shaping of the tubular endoplamic reticulum (ER). Although reticulon-like proteins have been identified in plants, very little is known about their cellular localization and functions. Here, we characterized the reticulon-like protein family of Arabidopsis thaliana. Three subfamilies can be distinguished on the basis of structural organization and sequence homology. We investigated the subcellular localization of two members of the larg…

ALS-Related Mutant FUS Protein Is Mislocalized to Cytoplasm and Is Recruited into Stress Granules of Fibroblasts from Asymptomatic <b><i>…

2017

<b><i>Background:</i></b> Amyotrophic lateral sclerosis (ALS) shows a strong genetic basis, with <i>SOD1</i>, <i>FUS</i>, <i>TARDBP</i>, and <i>C9ORF72 </i>being the genes most frequently involved<i>. </i>This has allowed identification of asymptomatic mutation carriers, which may be of help in understanding the molecular changes preceding disease onset. <b><i>Objectives:</i></b> We studied the cellular expression of FUS protein and the effect of heat-shock- and dithiothreitol-induced stress in fibroblasts from <i>FUS</i> P525L mutation carriers, healthy controls, and pati…

2017

Several studies have demonstrated that the expression of odorant receptors (ORs) occurs in various tissues. These findings have served as a basis for functional studies that demonstrate the potential of ORs as drug targets for a clinical application. To the best of our knowledge, this report describes the first evaluation of the mRNA expression of ORs and the localization of OR proteins in the human retina that set a stage for subsequent functional analyses. RNA-Sequencing datasets of three individual neural retinae were generated using Next-generation sequencing and were compared to previously published but reanalyzed datasets of the peripheral and the macular human retina and to reference…