Search results for "Activating protein"
showing 10 items of 25 documents
Quantitative proteomics reveals a dynamic association of proteins to detergent-resistant membranes upon elicitor signaling in tobacco.
2009
International audience; A large body of evidence from the past decade supports the existence, in membrane from animal and yeast cells, of functional microdomains playing important roles in protein sorting, signal transduction, or infection by pathogens. In plants, as previously observed for animal microdomains, detergent-resistant fractions, enriched in sphingolipids and sterols, were isolated from plasma membrane. A characterization of their proteic content revealed their enrichment in proteins involved in signaling and response to biotic and abiotic stress and cell trafficking suggesting that these domains were likely to be involved in such physiological processes. In the present study, w…
The integration of autophagy and cellular trafficking pathways via RAB GAPs.
2015
Macroautophagy is a conserved degradative pathway in which a double-membrane compartment sequesters cytoplasmic cargo and delivers the contents to lysosomes for degradation. Efficient formation and maturation of autophagic vesicles, so-called phagophores that are precursors to autophagosomes, and their subsequent trafficking to lysosomes relies on the activity of small RAB GTPases, which are essential factors of cellular vesicle transport systems. The activity of RAB GTPases is coordinated by upstream factors, which include guanine nucleotide exchange factors (RAB GEFs) and RAB GTPase activating proteins (RAB GAPs). A role in macroautophagy regulation for different TRE2-BUB2-CDC16 (TBC) dom…
Oligophrenin 1 mutations frequently cause X-linked mental retardation with cerebellar hypoplasia
2005
Background: Mutations of oligophrenin 1, one of the first genes identified in nonspecific X-linked mental retardation (MRX), have been described in patients with moderate to severe cognitive impairment and predominant cerebellar hypoplasia, in the vermis. Objective: To further delineate the phenotypic and mutational spectrum of the syndrome, by screening oligophrenin 1 in two cohorts of male patients with mental retardation (MR) with or without known posterior fossa anomalies. Methods: Clinical examination, cognitive testing, MRI studies, and mutational analysis (denaturing gradient gel electrophoresis and direct sequencing) on blood lymphocytes were performed in 213 unrelated affected indi…
Polymorphisms of cyclo-oxygenases and 5-lipo-oxygenase-activating protein are associated with chronic spontaneous urticaria and urinary leukotriene E4
2011
The mechanisms of chronic spontaneous urticaria (CSU) continue to be unknown. Our working hypothesis is that polymorphisms of cyclo-oxygenases and 5-lipo-oxygenase-activating protein may be involved in the pathways leading to CSU. We examined five candidate polymorphisms of cyclo-oxygenases 1 and 2 and of 5-lipo-oxygenase-activating protein in 109 controls and in 94 CSU patients from Northern Italy. We also examined the levels of urinary leukotriene E4 (LTE4) before and after challenge with ASA. A multiple regression model was found to show that COX-2 5'UTR T/G, COX-2 Exon 10 T/C, and FLAP -336 G/A polymorphisms were significantly associated with CSU, with the minor allele more represented …
A genome-wide association study of monozygotic twin-pairs suggests a locus related to variability of serum high-density lipoprotein cholesterol
2012
Serum lipid levels have been associated with cardiovascular diseases, metabolic syndrome and type II diabetes (Kannel et al., 1961; Miller & Miller, 1975; Pilia et al., 2006). Variation in lipids levels is highly influenced by heritable factors (Friedlander et al., 1997) and 95 loci have already been associated with levels of high density lipoprotein (HDL) cholesterol, low density lipoprotein (LDL) cholesterol, triglycerides (TG) and total cholesterol (TC) in numerous study samples and replicated in various populations using genome-wide approaches (Aulchenko et al., 2008; Kathiresan et al., 2008; Kooner et al., 2008; Teslovich et al., 2010; Willer et al., 2008). However, the genetic associa…
Decreasing dietary linoleic acid promotes long chain omega-3 fatty acid incorporation into rat retina and modifies gene expression
2011
International audience; Age-related macular degeneration (AMD) may be partially prevented by dietary habits privileging the consumption of ω3 long chain polyunsaturated fatty acids (ω3s) while lowering linoleic acid (LA) intake. The present study aimed to document whether following these epidemiological guidelines would enrich the neurosensory retina and RPE with ω3s and modulate gene expression in the neurosensory retina. Rat progenitors and pups were fed with diets containing low or high LA, and low or high ω3s. After scotopic single flash and 8-Hz-Flicker electroretinography, rat pups were euthanized at adulthood. The fatty acid profile of the neurosensory retina, RPE, liver, adipose tis…
The ARF GAPs ELMOD1 and ELMOD3 act at the Golgi and cilia to regulate ciliogenesis and ciliary protein traffic
2022
ELMODs are a family of three mammalian paralogs that display GTPase activating protein (GAP) activity towards a uniquely broad array of ADP-ribosylation factor (ARF) family GTPases that includes ARF-like (ARL) proteins. ELMODs are ubiquitously expressed in mammalian tissues, highly conserved across eukaryotes, and ancient in origin, being present in the last eukaryotic common ancestor. We described functions of ELMOD2 in immortalized mouse embryonic fibroblasts (MEFs) in the regulation of cell division, microtubules, ciliogenesis, and mitochondrial fusion. Here, using similar strategies with the paralogs ELMOD1 and ELMOD3, we identify novel functions and locations of these cell regulators a…
Competitive binding of Rab21 and p120RasGAP to integrins regulates receptor traffic and migration
2011
P120RasGAP competes with Rab21 for binding to the cytoplasmic domain of integrin α-subunits, thereby promoting receptor escape from early endosomes and recycling to the plasma membrane.
Roles for ELMOD2 and Rootletin in ciliogenesis.
2021
AbstractELMOD2 is a GTPase activating protein (GAP) with uniquely broad specificity for ARF family GTPases. We previously showed that it acts with ARL2 in mitochondrial fusion and microtubule stability and with ARF6 during cytokinesis. Mouse embryonic fibroblasts deleted for ELMOD2 also displayed changes in cilia related processes including increased ciliation, multiciliation, ciliary morphology, ciliary signaling, centrin accumulation inside cilia, and loss of rootlets at centrosomes with loss of centrosome cohesion. Increasing ARL2 activity or overexpressing Rootletin reversed these defects, revealing close functional links between the three proteins. This was further supported by the fin…
RAB3GAP1 and RAB3GAP2 modulate basal and rapamycin-induced autophagy
2014
Macroautophagy is a degradative pathway that sequesters and transports cytosolic cargo in autophagosomes to lysosomes, and its deterioration affects intracellular proteostasis. Membrane dynamics accompanying autophagy are mostly elusive and depend on trafficking processes. RAB GTPase activating proteins (RABGAPs) are important factors for the coordination of cellular vesicle transport systems, and several TBC (TRE2-BUB2-CDC16) domain-containing RABGAPs are associated with autophagy. Employing C. elegans and human primary fibroblasts, we show that RAB3GAP1 and RAB3GAP2, which are components of the TBC domain-free RAB3GAP complex, influence protein aggregation and affect autophagy at basal an…