Review
Biochemistry & Molecular Biology
Antonio Galindo, Sean Munro
Summary: Transport Protein Particle (TRAPP) complexes are conserved complexes that act as nucleotide exchange factors for Rab GTPases. They play roles in protein secretion, autophagy, and other processes. There are two complexes in metazoans: TRAPPII activates Rab11, and TRAPPIII activates Rab1. Crystal and cryo-EM structures have provided insights into the organization and activation mechanisms of these complexes.
Article
Cell Biology
Jieqiong Gao, Raffaele Nicastro, Marie-Pierre Peli-Gulli, Sophie Grziwa, Zilei Chen, Rainer Kurre, Jacob Piehler, Claudio De Virgilio, Florian Froehlich, Christian Ungermann
Summary: This study demonstrates the importance of SEs in maintaining cellular homeostasis during cell growth and proliferation. The function of the HOPS tethering complex is crucial for maintaining the identity of SEs and the activity of TORC1 on cell membranes.
JOURNAL OF CELL BIOLOGY
(2022)
Article
Cell Biology
Ayelen Gonzalez Montoro, Prado Vargas Duarte, Kathrin Auffarth, Stefan Walter, Florian Froehlich, Christian Ungermann
Summary: The hexameric HOPS complex is involved in tethering and promoting fusion events at the lysosome-like vacuole, and the Vps39 subunit has a specific role in vCLAMP formation. VCLAMPs and HOPS compete for the same pool of Vps39, and the CORVET subunit Vps3 can replace Vps39 in HOPS. This suggests a dynamic assembly of HOPS and CORVET complexes, with individual subunits like Vps39 participating in multiple functions while maintaining their role in tethering and fusion.
MOLECULAR BIOLOGY OF THE CELL
(2021)
Article
Biology
R. Sikora, P. Bun, L. Danglot, M. Alqabandi, P. Bassereau, F. Niedergang, T. Galli, A. Zahraoui
Summary: Secreted proteins are transported along intracellular route from the endoplasmic reticulum through the Golgi before reaching the plasma membrane. Small GTPase Rab and their effectors play a key role in membrane trafficking. MICAL-L1 is found to be associated with tubulo-vesicular structures and to have a significant colocalization with markers of the Golgi apparatus and recycling endosomes, revealing a new role in cargo delivery to the plasma membrane.
Article
Multidisciplinary Sciences
Natalia Gomez-Navarro, Julija Maldutyte, Kristina Poljak, Sew-Yeu Peak-Chew, Jonathon Orme, Brittany J. Bisnett, Caitlin H. Lamb, Michael Boyce, Davide Gianni, Elizabeth A. Miller
Summary: This study explores the possibility of selectively inhibiting protein secretion by perturbing protein-protein interactions involved in capture into transport vesicles. The researchers discovered a specific small molecule that can disrupt the function of the SEC24 protein, leading to decreased secretion of specific proteins.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Multidisciplinary Sciences
Gerard Duart, Assaf Elazar, Jonathan Y. Weinstein, Laura Gadea-Salom, Juan Ortiz-Mateu, Sarel J. Fleishman, Ismael Mingarro, Luis Martinez-Gil
Summary: Several methods have been developed to explore protein-protein interactions, but there is a need for more research on targeting transmembrane domains (TMDs). This study developed a computational approach to design sequences that can modulate protein-protein interactions in the membrane, and successfully applied it to BclxL. The findings enhance our understanding of protein-protein interactions in membranes and may lead to the development of inhibitors targeting TMD interactions.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Article
Cell Biology
Viktoria Szentgyoergyi, Anne Spang
Summary: Cargo delivery in cellular organelles relies on the fusion of vesicles with the help of tethering factors. Recent studies show that tethers play a significant role in membrane fusion, and the discovery of novel tether FERARI complex has changed our understanding of cargo transport.
JOURNAL OF CELL SCIENCE
(2023)
Article
Biochemistry & Molecular Biology
Antonio Galindo, Vicente J. Planelles-Herrero, Gianluca Degliesposti, Sean Munro
Summary: TRAPP complexes, which are nucleotide exchange factors, play vital roles in membrane traffic and autophagy. TRAPPII activates Rab11, while TRAPPIII activates Rab1, with shared core subunits affecting nucleotide exchange and specific large subunits essential for in vivo activity. Cryo-EM structures reveal the assembly of TRAPPIII complex, showing how TRAPPIII-specific subunits hold the catalytic core and large arms determine specificity. The lower resolution structure of TRAPPII suggests evolution from a single ur-TRAPP.
Article
Cell Biology
Futaba Osaki, Takahide Matsui, Shu Hiragi, Yuta Homma, Mitsunori Fukuda
Summary: A new engineered Rab11-specific binding domain (RBD11) was developed to visualize endogenous Rab11 and inhibit epithelial morphogenesis. Additionally, tools for temporally and reversibly analyzing Rab11-dependent membrane trafficking were also created in this study.
JOURNAL OF CELL SCIENCE
(2021)
Review
Cell Biology
Chad A. Sallaberry, Barbie J. Voss, Jaroslaw Majewski, Jacek Biernat, Eckhard Mandelkow, Eva Y. Chi, Crystal M. Vander Zanden
Summary: Misfolded tau protein is associated with various neurodegenerative diseases, particularly due to electrostatic interactions with anionic cellular membranes and membrane proteins, leading to the formation of reversible condensates and toxic oligomers at the membrane surface. Emerging evidence suggests that polyanionic membranes may serve as a site for phase-separated tau condensation, potentially regulating tau folding/misfolding and directing tau for native membrane-mediated functions.
FRONTIERS IN CELL AND DEVELOPMENTAL BIOLOGY
(2021)
Review
Biochemistry & Molecular Biology
Yuta Homma, Shu Hiragi, Mitsunori Fukuda
Summary: The Rab family of small GTPases plays a crucial role in regulating intracellular membrane trafficking by cycling between active and inactive states, controlled by GEFs and GAPs. Identification of new GEFs, GAPs, effectors, and post-translational modifications of Rabs have expanded our understanding of their functions beyond simple effector recruitment. Advances in CRISPR/Cas technology have accelerated knockout analyses, revealing previously unknown physiological roles of many Rabs.
Review
Oncology
Mitsunori Fukuda
Summary: Melanosomes, specialized organelles in melanocytes that produce and store melanin pigments, mature in stages and are transported to neighboring keratinocytes for pigment transfer. Rab GTPases play a crucial role in membrane trafficking processes important for skin and hair pigmentation.
PIGMENT CELL & MELANOMA RESEARCH
(2021)
Article
Multidisciplinary Sciences
Bijeta Prasai, Gideon J. Haber, Marie-Paule Strub, Regina Ahn, John A. Ciemniecki, Kem A. Sochacki, Justin W. Taraska
Summary: By utilizing correlative super-resolution light and electron microscopy, researchers have mapped the location and organization of Rab-GTPases and their effectors on exocytic vesicles, shedding light on their functional roles within cells.
NATURE COMMUNICATIONS
(2021)
Article
Plant Sciences
Emi Ito, Tomohiro Uemura
Summary: This article mainly introduces the basic principles of membrane traffic and its diversity in plants. Through the study of regulators in the trans-Golgi network, it summarizes their functions in different transport pathways and their roles in plant development and environmental stimuli.
JOURNAL OF PLANT RESEARCH
(2022)
Article
Multidisciplinary Sciences
Agnieszka Biernatowska, Paulina Olszewska, Krzysztof Grzymajlo, Dominik Drabik, Sebastian Kraszewski, Aleksander F. Sikorski, Aleksander Czogalla
Summary: Research has found that high-affinity complexes of MPP1 and flotillins are formed in erythroid cells, while overexpression of peptides containing a specific flotillin binding motif leads to disorganization of raft domains in erythroid precursor cells. This discovery highlights new molecular details concerning the mechanism whereby MPP1 functionally links flotillins to exert their physiological role in raft domain formation.
SCIENTIFIC REPORTS
(2021)
Article
Biology
Matthew L. Schwartz, Daniel P. Nickerson, Braden T. Lobingier, Rachael L. Plemel, Mengtong Duan, Cortney G. Angers, Michael Zick, Alexey J. Merz
Article
Microbiology
Rachel D. Hood, Pragya Singh, FoSheng Hsu, Tuezuen Guevener, Mike A. Carl, Rex R. S. Trinidad, Julie M. Silverman, Brooks B. Ohlson, Kevin G. Hicks, Rachael L. Plemel, Mo Li, Sandra Schwarz, Wenzhuo Y. Wang, Alexey J. Merz, David R. Goodlett, Joseph D. Mougous
CELL HOST & MICROBE
(2010)
Editorial Material
Microbiology
Siddharth Jaggavarapu, David S. Weiss
CELL HOST & MICROBE
(2018)
Article
Cell Biology
Matthew L. Schwartz, Alexey J. Merz
JOURNAL OF CELL BIOLOGY
(2009)
Article
Cell Biology
John R. Collette, Richard J. Chi, Douglas R. Boettner, Isabel M. Fernandez-Golbano, Rachael Plemel, Alex J. Merz, Maria Isabel Geli, Linton M. Traub, Sandra K. Lemmon
MOLECULAR BIOLOGY OF THE CELL
(2009)
Article
Biochemistry & Molecular Biology
Sheng-Ying Lo, Christopher L. Brett, Rachael L. Plemel, Marissa Vignali, Stanley Fields, Tamir Gonen, Alexey J. Merz
NATURE STRUCTURAL & MOLECULAR BIOLOGY
(2012)