Rab24 interacts with the Rab7/Rab interacting lysosomal protein complex to regulate endosomal degradation
Endocytosis is a multistep process engaged in extracellular molecules internalization. Several proteins including the Rab GTPases family coordinate the endocytic pathway. The small GTPase Rab7 is present in late endosome (LE) compartments being a marker of endosome maturation. The Rab interacting lysosomal protein (RILP) is a downstream effector of Rab7 that recruits the functional dynein/dynactin motor complex to late compartments. In the present study, we have found Rab24 as a component of the endosome‐lysosome degradative pathway. Rab24 is an atypical protein of the Rab GTPase family, which has been attributed a funct...
Source: Traffic - October 2, 2016 Category: Research Authors: Celina Amaya, Rodrigo D. Militello, Sebasti án D. Calligaris, María I. Colombo Tags: Original Article Source Type: research
KymoAnalyzer: A Software Tool for the Quantitative Analysis of Intracellular Transport in Neurons
Abstract
In axons, proper localization of proteins, vesicles, organelles, and other cargoes is accomplished by the highly regulated coordination of kinesins and dyneins, molecular motors that bind to cargoes and translocate them along microtubule (MT) tracks. Impairment of axonal transport is implicated in the pathogenesis of multiple neurodegenerative disorders including Alzheimer's and Huntington's diseases. To understand how MT‐based cargo motility is regulated and to delineate its role in neurodegeneration, it is critical to analyze the detailed dynamics of moving cargoes inside axons. Here, we present KymoAnalyzer, ...
Source: Traffic - September 30, 2016 Category: Research Authors: Sylvia Neumann, Romain Chassefeyre, George E. Campbell, Sandra E. Encalada Tags: Toolbox Source Type: research
14 ‐3‐3 proteins regulate K2P5.1 surface expression on T lymphocytes
ABSTRACT
K2P5.1 channels (also called TASK‐2 or KCNK5) have already been shown to be relevant in the pathophysiology of autoimmune disease since they are known to be upregulated on peripheral and central T lymphocytes of multiple sclerosis (MS) patients. Moreover, overexpression of K2P5.1 channels in vitro provokes enhanced T‐cell effector functions. However, the molecular mechanisms regulating intracellular K2P5.1 channel trafficking are unknown so far. Thus, the aim of the study is to elucidate the trafficking of K2P5.1 channels on T lymphocytes. Using mass spectrometry analysis, we have identified 14‐3‐3 protein...
Source: Traffic - September 30, 2016 Category: Research Authors: Juncal Fern ández‐Orth, Petra Ehling, Tobias Ruck, Susann Pankratz, Majella‐Sophie Hofmann, Peter Landgraf, Daniela C. Dieterich, Karl‐Heinz Smalla, Thilo Kähne, Guiscard Seebohm, Thomas Budde, Heinz Wiendl, Stefan Bittner, Sven G. Meuth Tags: Original Article Source Type: research
Polyglutamine toxicity in yeast uncovers phenotypic variations between different fluorescent protein fusions
In this study, we monitored toxicity and aggregation in a yeast model of Huntington's diseases to highlight the differential impact of the most common fluorescent proteins on the aggregation and toxicity of expanded polyglutamine proteins. (Source: Traffic)
Source: Traffic - September 30, 2016 Category: Research Authors: Yuwei Jiang, Sonja E. DiGregorio, Martin L. Duennwald, Patrick Lajoie Tags: Toolbox Source Type: research
Microbe ‐inducible trafficking pathways that control Toll‐like Receptor signaling
Abstract
The receptors of the mammalian innate immune system are designed for rapid microbial detection, and are located in organelles that are conducive to serve these needs. However, emerging evidence indicates that the sites of microbial detection are not the sites of innate immune signal transduction. Rather, microbial detection triggers the movement of receptors to regions of the cell where factors called sorting adaptors detect active receptors and promote downstream inflammatory responses. These findings highlight the critical role that membrane trafficking pathways play in the initiation of innate immunity to infec...
Source: Traffic - September 30, 2016 Category: Research Authors: Yunhao Tan, Jonathan C. Kagan Tags: Review Source Type: research
An evolutionary balance: conservation vs. innovation in ciliate membrane trafficking
Abstract
As most of eukaryotic diversity lies in single‐celled protists, they represent unique opportunities to ask questions about the balance of conservation and innovation in cell biological features. Among free‐living protists the ciliates offer ease of culturing, a rich array of experimental approaches, and versatile molecular tools, particularly in Tetrahymena thermophila and Paramecium tetraurelia. These attributes have been exploited by researchers to analyze a wealth of cellular structures in these large and complex cells. This mini‐review focuses on three aspects of ciliate membrane dynamics, all linked wit...
Source: Traffic - September 30, 2016 Category: Research Authors: Sabrice Guerrier, Helmut Plattner, Elizabeth H. Richardson, Joel B. Dacks, Aaron P. Turkewitz Tags: Review Source Type: research
Characterization of a caveolin ‐1 mutation associated with both PAH and congenital generalized lipodystrophy
ABSTRACT
Congenital generalized lipodystrophy (CGL) and pulmonary arterial hypertension (PAH) have recently been associated with mutations in the caveolin‐1 (CAV1) gene, which encodes the primary structural protein of caveolae. However, little is currently known about how these CAV1 mutations impact caveolae formation or contribute to the development of disease. Here, we identify a heterozygous F160X CAV1 mutation predicted to generate a C‐terminally truncated mutant protein in a patient with both PAH and CGL using whole exome sequencing, and characterize the properties of CAV1, caveolae‐associated proteins, and cave...
Source: Traffic - September 26, 2016 Category: Research Authors: Bing Han, Courtney A. Copeland, Yumeko Kawano, Erika Berman Rosenzweig, Eric D. Austin, Layla Shahmirzadi, Sha Tang, Krishnan Raghunathan, Wendy K. Chung, Anne K. Kenworthy Tags: Case Report Source Type: research
Vps35 ‐dependent recycling of Trem2 regulates microglial function
In this study, we showed that Trem2 in the plasma membrane underwent endocytosis and recycling. Trem2 is internalized in a clathrin‐dependent manner and then recycled back to the plasma membrane through Vps35, the key component of cargo recognition core of retromer complex, but not Rab11. When Vps35 is knocked down, Trem2 accumulated in the lysosomes but not degraded. More importantly, Vps35 deficiency leads to excessive LPS‐induced iNOS expression and IL‐6 production, which can be abolished by Trem2 overexpression. Furthermore, R47H Trem2, an Alzheimer's disease‐associated mutant, failed to interact with Vps35 and...
Source: Traffic - September 25, 2016 Category: Research Authors: Jie Yin, Xiaocui Liu, Qing He, Lujun Zhou, Zengqiang Yuan, Siqi Zhao Tags: Original Article Source Type: research
Newly synthesized and recycling pools of the apical protein gp135 do not occupy the same compartments
Abstract
Polarized epithelial cells sort newly synthesized and recycling plasma membrane proteins into distinct trafficking pathways directed to either the apical or basolateral membrane domains. While the trans Golgi network is a well‐established site of protein sorting, increasing evidence indicates a key role for endosomes in the initial trafficking of newly synthesized proteins. Both basolateral and apical proteins have been shown to traverse endosomes en route to the plasma membrane. In particular, apical proteins traffic through either subapical early or recycling endosomes. Here we use the SNAP tag system to analy...
Source: Traffic - September 20, 2016 Category: Research Authors: Emily H. Stoops, Michael Hull, Michael J. Caplan Tags: Original Article Source Type: research
Cadherin Tales: Regulation of Cadherin Function by Endocytic Membrane Trafficking
Abstract
Cadherins are the primary adhesion molecules in adherens junctions and desmosomes and play essential roles in embryonic development. Although significant progress has been made in understanding cadherin structure and function, we lack a clear vision of how cells confer plasticity upon adhesive junctions to allow for cellular rearrangements during development, wound healing, and metastasis. Endocytic membrane trafficking has emerged as a fundamental mechanism by which cells confer a dynamic state to adhesive junctions. Recent studies indicate that the juxtamembrane domain of classical cadherins contains multiple en...
Source: Traffic - September 14, 2016 Category: Research Authors: Chantel M. Cadwell, Wenji Su, Andrew P. Kowalczyk Tags: Review Source Type: research
Characterization of Endocytic Vesicles Using Magnetic Microbeads Coated with Signaling Ligands
(Source: Traffic)
Source: Traffic - September 12, 2016 Category: Research Authors: Hai ‐sheng Li, Donna B. Stolz, Guillermo Romero Tags: Corrigendum Source Type: research
Issue Information
(Source: Traffic)
Source: Traffic - September 12, 2016 Category: Research Tags: Issue Information Source Type: research
Issue Cover (October 2016)
Cover legend: Occurrence of vesicles in a chloroplast at ambient temperature in a subepidermal cell of the proximal part of young, immature (still green) fruit pericarp of squash. See Lindquist et al. Traffic 2016; 17(10):1125–1138.
Read the full article on doi:10.1111/tra.12427 (Source: Traffic)
Source: Traffic - September 12, 2016 Category: Research Tags: Issue Cover Source Type: research
An antimicrobial origin of transit peptides accounts for early endosymbiotic events
Abstract
Primary endosymbiosis, which gave rise to mitochondria or chloroplasts, required successful targeting of a number of proteins from the host cytosol to the endosymbiotic organelles. A survey of studies published in separate fields of biological research over the past forty years argue for an antimicrobial origin of targeting peptides. It is proposed that mitochondria and chloroplast derive from microbes that developed a resistance strategy to antimicrobial peptides that consisted in their rapid internalization and proteolytic disposal by microbial peptidases.
Primary endosymbiosis, which gave rise to mitochondria...
Source: Traffic - September 12, 2016 Category: Research Authors: Francis ‐André Wollman Tags: Traffic Interchange Source Type: research
Cresyl violet: a superior fluorescent lysosomal marker
ABSTRACT
We have characterized cresyl violet as a membrane‐permeant fluorophore that localizes to lysosomes and acidic vacuoles of budding yeast, Drosophila, human, murine and canine cells. An acidotropic weak base, cresyl violet is shown to be virtually insensitive to physiological alkali and divalent cations. Because of its unique spectral properties, it can be used in combination with green, red and far‐red fluorophores, is less susceptible to photobleaching than alternative acidotropic probes, and does not undergo photoconversion. At concentrations that yield bright labeling of acidic compartments, cresyl violet do...
Source: Traffic - August 31, 2016 Category: Research Authors: Philip P. Ostrowski, Gregory D. Fairn, Sergio Grinstein, Danielle E. Johnson Tags: Toolbox Source Type: research
