journal
MENU ▼
Read by QxMD icon Read
search

Small GTPases

journal
https://www.readbyqxmd.com/read/28146371/critical-importance-of-rab-proteins-for-synaptic-function
#1
Maria Lidia Mignogna, Patrizia D'Adamo
Neurons are highly polarized cells that exhibit one of the more complex morphology and function. Neuronal intracellular trafficking plays a key role in dictating the directionality and specificity of vesicle formation, transport and fusion, allowing the transmission of information in sophisticate cellular network. Thus, the integrity of protein trafficking and spatial organization is especially important in neuronal cells. RAB proteins, small monomeric GTPases belonging to the RAS superfamily, spatially and temporally orchestrate specific vesicular trafficking steps...
February 1, 2017: Small GTPases
https://www.readbyqxmd.com/read/28136018/co-existence-of-ras-activation-in-a-chemotactic-signal-transduction-pathway-and-in-an-autonomous-wave-forming-system
#2
Mary Ecke, Günther Gerisch
The activation of Ras is common to two activities in cells of Dictyostelium discoideum: the directed movement in a gradient of chemoattractant and the autonomous generation of propagating waves of actin polymerization on the substrate-attached cell surface. We produced large cells by electric-pulse induced fusion to simultaneously study both activities in one cell. For imaging, a fluorescent label for activated Ras was combined with labels for filamentous actin, PIP3, or PTEN. Chemotactic responses were elicited in a diffusion gradient of cyclic AMP...
January 31, 2017: Small GTPases
https://www.readbyqxmd.com/read/28135905/new-insights-into-the-function-of-rab-gtpases-in-the-context-of-exosomal-secretion
#3
Lionel Blanc, Michel Vidal
In the last two decades, extracellular vesicle-mediated communication between cells has become a major field in cell biology. However, the function of extracellular vesicles is far from clear, especially due to the disparity of released vesicles by cells. Basically, one must consider vesicles budding from the cell plasma membrane (ectosomes) and vesicles released upon fusion of an endosomal multivesicular compartment (exosomes). Moreover, even for exosomes, we report and discuss here the possibility that different routes regulated by specific Rab GTPases might produce exosomes having various biologic functions...
January 31, 2017: Small GTPases
https://www.readbyqxmd.com/read/28129089/activation-of-compensatory-pathways-via-rac2-in-the-absence-of-the-cdc42-effector-wiskott-aldrich-syndrome-protein-in-dendritic-cells
#4
Marisa A P Baptista, Lisa S Westerberg
There is extensive crosstalk between different Rho GTPases, including Cdc42, Rac1, and Rac2, and they can activate or inhibit the activity of each other. Dendritic cells express both Rac1 and Rac2. Due to posttranslational modification of lipid anchors, Rac1 localizes mainly to the plasma membrane whereas Rac2 localizes to the phagosomal membrane where it assembles the NADPH complex. Our recent study of primary immunodeficiency disease caused by mutations in the Cdc42 effector Wiskott-Aldrich syndrome protein (WASp) has shed light on the compensatory mechanisms between Rho GTPases and their effector proteins...
January 27, 2017: Small GTPases
https://www.readbyqxmd.com/read/28129039/coordination-of-synaptic-vesicle-trafficking-and-turnover-by-the-rab35-signaling-network
#5
Patricia Sheehan, Clarissa L Waites
Rab35 and the Rab35 network of GAPs, GEFs, and effectors are important regulators of membrane trafficking for a variety of cellular processes, from cytokinesis and phagocytosis to neurite outgrowth. In the past five years, components of this signaling network have also been implicated as critical mediators of synaptic vesicle (SV) recycling and protein homeostasis. Recent studies by several groups, including our own, have demonstrated that Rab35-mediated endosomal sorting is required for the degradation of SV proteins via the ESCRT pathway, thereby eliminating old or damaged proteins from the SV pool...
January 27, 2017: Small GTPases
https://www.readbyqxmd.com/read/28129038/regulation-of-small-gtpase-activity-by-g1-cyclins
#6
Neus Pedraza, Tània Cemeli, Ma Ventura Monserrat, Eloi Garí, Francisco Ferrezuelo
Together with a cyclin-dependent kinase (CDK) partner G1 cyclins control cell cycle entry by phosphorylating a number of nuclear targets and releasing a transcriptional program at the end of G1 phase. Yeast G1 cyclins also operate on cytoplasmic targets involved in the polarization of the cytoskeleton and vesicle trafficking. These processes are mainly controlled by the small GTPase Cdc42, and G1 cyclins regulate the activity of this and other small GTPases through the modulation of their regulators and effectors...
January 27, 2017: Small GTPases
https://www.readbyqxmd.com/read/28129037/multivalency-in-rab-effector-interactions
#7
Amrita Rai, Roger S Goody, Matthias P Müller
Rab proteins regulate vesicular transport in eukaryotic cells and establish connections to various cellular structures and processes by interacting with so-called effector molecules. Several of these effectors are known to not only bind a single Rab protein, but to be able to bind multiple different Rabs simultaneously. In this review we will give a short overview of effectors in general and (putative) functions of the aforementioned multivalent Rab:effector interactions.
January 27, 2017: Small GTPases
https://www.readbyqxmd.com/read/28129035/where-no-ras-has-gone-before-vps35-steers-n-ras-through-the-cytosol
#8
Mo Zhou, Mark R Philips
Ras is the best-studied member of the superfamily of small GTPases because of its role in cancer. Ras proteins transmit signals for proliferation, differentiation and survival. Three RAS genes encode 4 isoforms. All Ras isoforms have long been considered membrane bound, a localization required for function. Our recent study revealed that N-Ras differs from all other isoforms in being largely cytosolic even following modification with a prenyl lipid. Endogenous, cytosolic N-Ras chromatographed in both high and low molecular weight pools, a pattern that required prenylation, suggesting prenyl-dependent interaction with other proteins...
January 27, 2017: Small GTPases
https://www.readbyqxmd.com/read/28125340/rabs-set-the-stage-for-polarity
#9
Sara S Parker, Christopher Cox, Jean M Wilson
Cell polarity refers to the asymmetric localization of cellular components that allows cells to carry out their specialized functions, be they epithelial barrier function, transmission of action potentials in nerve cells, or modulation of the immune response. The establishment and maintenance of cell polarity requires the directed trafficking of membrane proteins and lipids - essential processes that are mediated by Rab GTPases. Interestingly, several of the Rabs that impact polarity are present in the earliest eukaryotes, and the Rab polarity repertoire has expanded as cells have become more complex...
January 26, 2017: Small GTPases
https://www.readbyqxmd.com/read/28125336/new-insights-into-mechanisms-of-nuclear-translocation-of-g-protein-coupled-receptors
#10
Vikrant K Bhosle, José Carlos Rivera, Sylvain Chemtob
The G-protein coupled receptor (GPCR) signaling was long believed to involve activation of receptor exclusively at the cell surface, followed by its binding to heterotrimeric G-proteins and arrestins to trigger various intracellular signaling cascades, and termination of signaling by internalization of the receptor. It is now accepted that many GPCRs continue to signal after internalization in the endosomes. Since the breakthrough discoveries of nuclear binding sites for their ligands in 1980s, several GPCRs have been detected at cell nuclei...
January 26, 2017: Small GTPases
https://www.readbyqxmd.com/read/28125332/the-versatility-of-rhoa-activities-in-neural-differentiation
#11
Arie Horowitz, Junning Yang, Jingli Cai, Lorraine Iacovitti
In this commentary we discuss a paper we published recently on the activities of the GTPase RhoA during neural differentiation of murine embryonic stem cells, and relate our findings to previous studies. We narrate how we found that RhoA impedes neural differentiation by inhibiting the production as well as the secretion of noggin, a soluble factor that antagonizes bone morphogenetic protein. We discuss how the questions we tried to address shaped the study, and how embryonic stem cells isolated from a genetically modified mouse model devoid of Syx, a RhoA-specific guanine exchange factor, were used to address them...
January 26, 2017: Small GTPases
https://www.readbyqxmd.com/read/28125329/role-of-rab-gtpases-in-the-export-trafficking-of-g-protein-coupled-receptors
#12
Guansong Wang, Zhe Wei, Guangyu Wu
G protein-coupled receptors (GPCRs) constitute a superfamily of cell surface receptors that regulate a variety of cell functions. As the cell surface is the functional destination for most GPCRs, the cell surface targeting process represents a crucial checkpoint in controlling the functionality of the receptors. However, the molecular mechanisms underlying the cell surface delivery of newly synthesized GPCRs remain poorly understood. In this review, we will highlight the role of Rab GTPases in GPCR cell surface transport, particularly post-Golgi traffic, and discuss the underlying molecular mechanisms...
January 26, 2017: Small GTPases
https://www.readbyqxmd.com/read/28118081/rabs-on-the-fly-functions-of-rab-gtpases-during-development
#13
Sara Caviglia, David Flores-Benitez, Johanna Lattner, Stefan Luschnig, Marko Brankatschk
The organisation of intracellular transport processes is adapted specifically to different cell types, developmental stages, and physiological requirements. Some protein traffic routes are universal to all cells and constitutively active, while other routes are cell-type specific, transient, and induced under particular conditions only. Small GTPases of the Rab (Ras related in brain) subfamily are conserved across eukaryotes and regulate most intracellular transit pathways. The complete sets of Rab proteins have been identified in model organisms, and molecular principles underlying Rab functions have been uncovered...
January 24, 2017: Small GTPases
https://www.readbyqxmd.com/read/28103137/cap-gly-proteins-contribute-to-microtubule-dependent-trafficking-via-interactions-with-the-c-terminal-aromatic-residue-of-%C3%AE-tubulin
#14
Annie Andrieux, Laurence Aubry, Cécile Boscheron
In mammals, the C-terminal tyrosine residue of α-tubulin is subjected to removal/re-addition cycles resulting in tyrosinated microtubules and detyrosinated Glu-microtubules. CLIP170 and its yeast ortholog (Bik1) interact weakly with Glu-microtubules. Recently, we described a Microtubule- Rho1- and Bik1-dependent mechanism involved in Snc1 routing. Here, we further show a contribution of the yeast p150Glued ortholog (Nip100) in Snc1 trafficking. Both CLIP170 and p150Glued are CAP-Gly-containing proteins that belong to the microtubule +end-tracking protein family (known as +Tips)...
January 19, 2017: Small GTPases
https://www.readbyqxmd.com/read/28060560/harnessing-membrane-trafficking-to-promote-cancer-spreading-and-invasion-the-case-of-rab2a
#15
Hiroaki Kajiho, Yuko Kajiho, Giorgio Scita
How cancer disseminates and metastasizes remains an outstanding open question. Emerging evidence indicates that membrane trafficking is frequently harnessed by tumors of epithelial origin to acquire a mesenchymal program of invasiveness. However, the critical molecular hubs used by cancer cells this context have only began to be elucidated. Here, we discussed the results of a recent phenotypic screening that led to the identification of the small GTPase RAB2A, not previously involved in cancer dissemination, as pivotal for the acquisition of pericellular proteolysis, cell dissemination and distant metastatic spreading of human breast cancer...
January 6, 2017: Small GTPases
https://www.readbyqxmd.com/read/28055293/epidermal-activation-of-the-small-gtpase-rac1-in-psoriasis-pathogenesis
#16
Mårten C G Winge, M Peter Marinkovich
The small GTPase Ras-related C3 botulinum toxin substrate 1 (RAC1) plays a central role in skin homeostasis, including barrier function, wound healing and inflammatory responses. Psoriasis is a common skin disease characterized by deregulation of these functions, and affected skin exhibit keratinocyte hyperproliferation, inflammation and immune cell infiltration. Although psoriasis is often triggered by environmental stimulus, there is a strong genetic association with genes expressed in both immune cells and keratinocytes, of which several are linked to Rac1 signaling...
January 5, 2017: Small GTPases
https://www.readbyqxmd.com/read/28055292/molecular-control-of-rab-activity-by-gefs-gaps-and-gdi
#17
Matthias P Müller, Roger S Goody
Rab proteins are the major regulators of vesicular trafficking in eukaryotic cells. Their activity can be tightly controlled within cells: Regulated by guanine nucleotide exchange factors (GEFs) and GTPase activating proteins (GAPs), they switch between an active GTP-bound state and an inactive GDP-bound state, interacting with downstream effector proteins only in the active state. Additionally, they can bind to membranes via C-terminal prenylated cysteine residues and they can be solubilized and shuttled between membranes by chaperone-like molecules called GDP dissociation inhibitors (GDIs)...
January 5, 2017: Small GTPases
https://www.readbyqxmd.com/read/28005455/small-gtpases-controlling-autophagy-related-membrane-traffic-in-yeast-and-metazoans
#18
Szabolcs Takáts, Attila Boda, Tamás Csizmadia, Gábor Juhász
During macroautophagy, the phagophore-mediated formation of autophagosomes and their subsequent fusion with lysosomes requires extensive transformation of the endomembrane system. Membrane dynamics in eukaryotic cells is regulated by small GTPase proteins including Arfs and Rabs. The small GTPase proteins that regulate autophagic membrane traffic are mostly conserved in yeast and metazoans, but there are also several differences. In this mini-review, we compare the small GTPase network of yeast and metazoan cells that regulates autophagy, and point out the similarities and differences in these organisms...
December 22, 2016: Small GTPases
https://www.readbyqxmd.com/read/28001501/the-small-gtpase-arf6-regulates-protein-trafficking-to-control-cellular-function-during-development-and-in-disease
#19
Allie H Grossmann, Helong Zhao, Noah Jenkins, Weiquan Zhu, Jackson R Richards, Jae Hyuk Yoo, Jacob M Winter, Bianca Rich, Tara M Mleynek, Dean Y Li, Shannon J Odelberg
The activation of the small GTPase ARF6 has been implicated in promoting several pathological processes related to vascular instability and tumor formation, growth, and metastasis. ARF6 also plays a vital role during embryonic development. Recent studies have suggested that ARF6 carries out these disparate functions primarily by controlling protein trafficking within the cell. ARF6 helps direct proteins to intracellular or extracellular locations where they function in normal cellular responses during development and in pathological processes later in life...
December 21, 2016: Small GTPases
https://www.readbyqxmd.com/read/27936345/targeting-integrin-linked-kinase-to-suppress-oncogenic-kras-signaling-in-pancreatic-cancer
#20
Po-Chen Chu, Samuel K Kulp, Tanios Bekaii-Saab, Ching-Shih Chen
Although oncogenic KRAS represents a therapeutically relevant target in pancreatic cancer, it is deemed "non-druggable" because of the intrinsic difficulty in designing direct inhibitors of KRAS. Our recent work demonstrated a KRAS-integrin-linked kinase (ILK) regulatory feedback loop that allows pancreatic cancer cells to regulate KRAS expression and to interact with the tumor microenvironment to promote aggressive phenotype. KRAS induces E2F1-mediated transcriptional activation of ILK expression, and ILK, in turn, controls KRAS expression via hnRNPA1, which binds and destabilizes the G-quadruplex in the KRAS promoter...
December 9, 2016: Small GTPases
journal
journal
43017
1
2
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"