The ESCRT machinery: new functions in viral and cellular biology

2009 ◽  
Vol 37 (1) ◽  
pp. 195-199 ◽  
Author(s):  
Jeremy G. Carlton ◽  
Juan Martin-Serrano
Keyword(s):  
Cell Division ◽  
Multivesicular Body ◽  
Cellular Biology ◽  
Cytosolic Proteins ◽  
Body Formation ◽  
Endosomal Sorting ◽  
Escrt Machinery ◽  
Viral Egress

The ESCRT (endosomal sorting complex required for transport) machinery consists of a number of cytosolic proteins that make up three functional subcomplexes: ESCRT-I, ESCRT-II and ESCRT-III. These proteins function in multivesicular body formation and cell division and are co-opted by enveloped retroviruses to facilitate viral egress. Analysis of these functions may help illuminate conserved mechanisms of ESCRT function.

scholarly journals VPS37A directs ESCRT recruitment for phagophore closure

2019 ◽  
Vol 218 (10) ◽  
pp. 3336-3354 ◽  
Author(s):  
Yoshinori Takahashi ◽  
Xinwen Liang ◽  
Tatsuya Hattori ◽  
Zhenyuan Tang ◽  
Haiyan He ◽  
...  
Keyword(s):  
Mammalian Cells ◽  
Growth Factor Receptor ◽  
Multivesicular Body ◽  
Regulatory Mechanisms ◽  
Endosomal Sorting ◽  
Aaa Atpase ◽  
Escrt Machinery ◽  
Genome Wide ◽  
A Genome ◽  
Epidermal Growth

The process of phagophore closure requires the endosomal sorting complex required for transport III (ESCRT-III) subunit CHMP2A and the AAA ATPase VPS4, but their regulatory mechanisms remain unknown. Here, we establish a FACS-based HaloTag-LC3 autophagosome completion assay to screen a genome-wide CRISPR library and identify the ESCRT-I subunit VPS37A as a critical component for phagophore closure. VPS37A localizes on the phagophore through the N-terminal putative ubiquitin E2 variant domain, which is found to be required for autophagosome completion but dispensable for ESCRT-I complex formation and the degradation of epidermal growth factor receptor in the multivesicular body pathway. Notably, loss of VPS37A abrogates the phagophore recruitment of the ESCRT-I subunit VPS28 and CHMP2A, whereas inhibition of membrane closure by CHMP2A depletion or VPS4 inhibition accumulates VPS37A on the phagophore. These observations suggest that VPS37A coordinates the recruitment of a unique set of ESCRT machinery components for phagophore closure in mammalian cells.

scholarly journals Unexpected organellar locations of ESCRT machinery in Giardia intestinalis and complex evolutionary dynamics spanning the transition to parasitism in the lineage Fornicata

BMC Biology ◽  
2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Shweta V. Pipaliya ◽  
Rui Santos ◽  
Dayana Salas-Leiva ◽  
Erina A. Balmer ◽  
Corina D. Wirdnam ◽  
...  
Keyword(s):  
Evolutionary Dynamics ◽  
Gastrointestinal Disease ◽  
Multivesicular Body ◽  
Giardia Intestinalis ◽  
Endosomal Sorting ◽  
Escrt Machinery ◽  
Parasitic Lifestyle ◽  
Cellular Compartments ◽  
Related Proteins ◽  
First Time

Abstract Background Comparing a parasitic lineage to its free-living relatives is a powerful way to understand how that evolutionary transition to parasitism occurred. Giardia intestinalis (Fornicata) is a leading cause of gastrointestinal disease world-wide and is famous for its unusual complement of cellular compartments, such as having peripheral vacuoles instead of typical endosomal compartments. Endocytosis plays an important role in Giardia’s pathogenesis. Endosomal sorting complexes required for transport (ESCRT) are membrane-deforming proteins associated with the late endosome/multivesicular body (MVB). MVBs are ill-defined in G. intestinalis, and roles for identified ESCRT-related proteins are not fully understood in the context of its unique endocytic system. Furthermore, components thought to be required for full ESCRT functionality have not yet been documented in this species. Results We used genomic and transcriptomic data from several Fornicata species to clarify the evolutionary genome streamlining observed in Giardia, as well as to detect any divergent orthologs of the Fornicata ESCRT subunits. We observed differences in the ESCRT machinery complement between Giardia strains. Microscopy-based investigations of key components of ESCRT machinery such as GiVPS36 and GiVPS25 link them to peripheral vacuoles, highlighting these organelles as simplified MVB equivalents. Unexpectedly, we show ESCRT components associated with the endoplasmic reticulum and, for the first time, mitosomes. Finally, we identified the rare ESCRT component CHMP7 in several fornicate representatives, including Giardia and show that contrary to current understanding, CHMP7 evolved from a gene fusion of VPS25 and SNF7 domains, prior to the last eukaryotic common ancestor, over 1.5 billion years ago. Conclusions Our findings show that ESCRT machinery in G. intestinalis is far more varied and complete than previously thought, associates to multiple cellular locations, and presents changes in ESCRT complement which pre-date adoption of a parasitic lifestyle.

scholarly journals Efficient Cargo Sorting by ESCRT-I and the Subsequent Release of ESCRT-I from Multivesicular Bodies Requires the Subunit Mvb12

2007 ◽  
Vol 18 (2) ◽  
pp. 636-645 ◽  
Author(s):  
Matt Curtiss ◽  
Charles Jones ◽  
Markus Babst
Keyword(s):  
Protein Complex ◽  
Transmembrane Proteins ◽  
Multivesicular Body ◽  
Multivesicular Bodies ◽  
Rapid Degradation ◽  
Endosomal Sorting ◽  
Escrt Machinery ◽  
Complex Functions ◽  
Vacuolar Protein ◽  
Cargo Sorting

The endosomal sorting complex required for transport (ESCRT)-I protein complex functions in recognition and sorting of ubiquitinated transmembrane proteins into multivesicular body (MVB) vesicles. It has been shown that ESCRT-I contains the vacuolar protein sorting (Vps) proteins Vps23, Vps28, and Vps37. We identified an additional subunit of yeast ESCRT-I called Mvb12, which seems to associate with ESCRT-I by binding to Vps37. Transient recruitment of ESCRT-I to MVBs results in the rapid degradation of Mvb12. In contrast to mutations in other ESCRT-I subunits, which result in strong defects in MVB cargo sorting, deletion of MVB12 resulted in only a partial sorting phenotype. This trafficking defect was fully suppressed by overexpression of the ESCRT-II complex. Mutations in MVB12 did not affect recruitment of ESCRT-I to MVBs, but they did result in delivery of ESCRT-I to the vacuolar lumen via the MVB pathway. Together, these observations suggest that Mvb12 may function in regulating the interactions of ESCRT-I with cargo and other proteins of the ESCRT machinery to efficiently coordinate cargo sorting and release of ESCRT-I from the MVB.

Cell Polarity and Migration: Emerging Role for the Endosomal Sorting Machinery

Physiology ◽  
2011 ◽  
Vol 26 (3) ◽  
pp. 171-180 ◽  
Author(s):  
Viola Hélène Lobert ◽  
Harald Stenmark
Keyword(s):  
Cell Migration ◽  
Cell Division ◽  
Cell Polarity ◽  
Tumor Suppressors ◽  
Potential Role ◽  
Endosomal Sorting ◽  
Escrt Machinery ◽  
Viral Budding ◽  
And Migration

The endosomal sorting complex required for transport (ESCRT) machinery has been implicated in the regulation of endosomal sorting, cell division, viral budding, autophagy, and cell signaling. Here, we review recent evidence that implicates ESCRTs in cell polarity and cell migration, and discuss the potential role of ESCRTs as tumor suppressors.

scholarly journals Regulation of Vps4 ATPase activity by ESCRT-III

2009 ◽  
Vol 37 (1) ◽  
pp. 143-145 ◽  
Author(s):  
Brian A. Davies ◽  
Ishara F. Azmi ◽  
David J. Katzmann
Keyword(s):  
Atpase Activity ◽  
Multivesicular Body ◽  
Critical Function ◽  
Body Formation ◽  
Temporal Regulation ◽  
Endosomal Sorting ◽  
Aaa Atpase ◽  
Endosomal Membrane ◽  
Endosomal Membranes ◽  
Vacuolar Protein

MVB (multivesicular body) formation occurs when the limiting membrane of an endosome invaginates into the intraluminal space and buds into the lumen, bringing with it a subset of transmembrane cargoes. Exvagination of the endosomal membrane from the cytosol is topologically similar to the budding of retroviral particles and cytokinesis, wherein membranes bud away from the cytoplasm, and the machinery responsible for MVB sorting has been implicated in these phenomena. The AAA (ATPase associated with various cellular activities) Vps4 (vacuolar protein sorting 4) performs a critical function in the MVB sorting pathway. Vps4 appears to dissociate the ESCRTs (endosomal sorting complexes required for transport) from endosomal membranes during the course of MVB sorting, but it is unclear how Vps4 ATPase activity is synchronized with ESCRT release. We have investigated the mechanisms by which ESCRT components stimulate the ATPase activity of Vps4. These studies support a model wherein Vps4 activity is subject to spatial and temporal regulation via distinct mechanisms during MVB sorting.

scholarly journals Essential Role of hIST1 in Cytokinesis

2009 ◽  
Vol 20 (5) ◽  
pp. 1374-1387 ◽  
Author(s):  
Monica Agromayor ◽  
Jez G. Carlton ◽  
John P. Phelan ◽  
Daniel R. Matthews ◽  
Leo M. Carlin ◽  
...  
Keyword(s):  
Mammalian Cells ◽  
Multivesicular Body ◽  
Endosomal Sorting ◽  
Escrt Machinery ◽  
Membrane Fission ◽  
Immunodeficiency Virus ◽  
Positive Modulator ◽  
Essential Function ◽  
Hiv 1

The last steps of multivesicular body (MVB) formation, human immunodeficiency virus (HIV)-1 budding and cytokinesis require a functional endosomal sorting complex required for transport (ESCRT) machinery to facilitate topologically equivalent membrane fission events. Increased sodium tolerance (IST) 1, a new positive modulator of the ESCRT pathway, has been described recently, but an essential function of this highly conserved protein has not been identified. Here, we describe the previously uncharacterized KIAA0174 as the human homologue of IST1 (hIST1), and we report its conserved interaction with VPS4, CHMP1A/B, and LIP5. We also identify a microtubule interacting and transport (MIT) domain interacting motif (MIM) in hIST1 that is necessary for its interaction with VPS4, LIP5 and other MIT domain-containing proteins, namely, MITD1, AMSH, UBPY, and Spastin. Importantly, hIST1 is essential for cytokinesis in mammalian cells but not for HIV-1 budding, thus providing a novel mechanism of functional diversification of the ESCRT machinery. Last, we show that the hIST1 MIM activity is essential for cytokinesis, suggesting possible mechanisms to explain the role of hIST1 in the last step of mammalian cell division.

scholarly journals Toxoplasma gondii subverts the host ESCRT machinery for parasite uptake of host cytosolic proteins

2021 ◽  
Author(s):  
Yolanda Rivera-Cuevas ◽  
Joshua Mayoral ◽  
Manlio Di Cristina ◽  
Anna-Lisa E. Lawrence ◽  
Einar B. Olafsson ◽  
...  
Keyword(s):  
Toxoplasma Gondii ◽  
Parasitophorous Vacuole ◽  
Dense Granule ◽  
Cytosolic Proteins ◽  
Endosomal Sorting ◽  
Dense Granules ◽  
Escrt Machinery ◽  
Late Domain ◽  
Cytosolic Protein ◽  
Hiv Virus

Toxoplasma gondii is a master manipulator capable of effectively siphoning the resources from the host cell for its intracellular subsistence. However, the molecular underpinnings of how the parasite gains resources from its host remain largely unknown. Residing within a non-fusogenic parasitophorous vacuole, the parasite must acquire resources across the limiting membrane of its replicative niche, which is decorated with parasite proteins including those secreted from dense granules. We discovered a role for the Endosomal Sorting Complex Required for Transport (ESCRT) machinery in host cytosolic protein uptake by T. gondii by disrupting host ESCRT function. We identified the transmembrane dense granule protein TgGRA14, which contains motifs homologous to the late domain motifs of HIV-1 Gag, as a candidate for the recruitment of the host ESCRT machinery to the PV membrane. Using an HIV virus-like particle (VLP) release assay, we found that the motif-containing portion of TgGRA14 is sufficient to substitute for HIV Gag late domain to mediate ESCRT-dependent VLP budding. We also show that TgGRA14 is proximal to and interacts with host ESCRT components and other dense granule proteins during infection. Furthermore, analysis of GRA14-deficient parasites revealed a marked reduction in ingestion of a host cytosolic protein compared to WT parasites. Thus, we propose a model in which T. gondii recruits the host ESCRT machinery to the PV where it can interact with TgGRA14 for the internalization of host cytosolic proteins across the PVM. These findings provide new insight into how T. gondii accesses contents of the host cytosol by exploiting a key pathway for vesicular budding and membrane scission.

scholarly journals Unexpected organellar locations of ESCRT machinery in Giardia intestinalis and complex evolutionary dynamics spanning the transition to parasitism in the lineage Fornicata

2021 ◽  
Author(s):  
Shweta V. Pipaliya ◽  
Rui Santos ◽  
Dayana Salas-Leiva ◽  
Erina A. Balmer ◽  
Corina D. Wirdnam ◽  
...  
Keyword(s):  
Evolutionary Dynamics ◽  
Gastrointestinal Disease ◽  
Multivesicular Body ◽  
Giardia Intestinalis ◽  
Endosomal Sorting ◽  
Escrt Machinery ◽  
Parasitic Lifestyle ◽  
Cellular Compartments ◽  
Related Proteins ◽  
First Time

ABSTRACTComparing a parasitic lineage to its free-living relatives is a powerful way to understand how the evolutionary transition to parasitism occurred. Giardia intestinalis (Fornicata) is a leading cause of gastrointestinal disease world-wide and is famous for its unusual complement of cellular compartments, such as having peripheral vacuoles instead of typical endosomal compartments. Endocytosis plays an important role in Giardia’s pathogenesis. Endosomal sorting complexes required for transport (ESCRT) are membrane-deforming proteins associated with the late endosome/multivesicular body (MVB). MVBs are ill-defined in G. intestinalis and roles for identified ESCRT-related proteins are not fully understood in the context of its unique endocytic system. Furthermore, components thought to be required for full ESCRT functionality have not yet been documented in this species.We used genomic and transcriptomic data from several Fornicata species to clarify the evolutionary genome streamlining observed in Giardia, as well as to detect any divergent orthologs of the Fornicata ESCRT subunits. We observed differences in the ESCRT machinery complement between Giardia strains. Microscopy-based investigations of key components of ESCRT machinery such as GiVPS36and GiVPS25 link them to peripheral vacuoles, highlighting these organelles as simplified MVB equivalents. Unexpectedly, we show ESCRT components associated with the Endoplasmic Reticulum, and for the first time, mitosomes. Finally, we identified the rare ESCRT component CHMP7 in several fornicate representatives, including Giardia, and show that contrary to current understanding, CHMP7 evolved from a gene fusion of VPS25 and SNF7 domains, prior to the last eukaryotic common ancestor, over 1.5 billion years ago. Our findings show that ESCRT machinery in G. intestinalis is far more varied and complete than previously thought, and associating to multiple cellular locations and presenting changes in ESCRT complement which pre-date adoption of a parasitic lifestyle.

scholarly journals Toxoplasma gondii exploits the host ESCRT machinery for parasite uptake of host cytosolic proteins

2021 ◽  
Vol 17 (12) ◽  
pp. e1010138
Author(s):  
Yolanda Rivera-Cuevas ◽  
Joshua Mayoral ◽  
Manlio Di Cristina ◽  
Anna-Lisa E. Lawrence ◽  
Einar B. Olafsson ◽  
...  
Keyword(s):  
Toxoplasma Gondii ◽  
Parasitophorous Vacuole ◽  
Dense Granule ◽  
Cytosolic Proteins ◽  
Endosomal Sorting ◽  
Dense Granules ◽  
Escrt Machinery ◽  
Late Domain ◽  
Cytosolic Protein ◽  
Hiv 1

Toxoplasma gondii is a master manipulator capable of effectively siphoning the resources from the host cell for its intracellular subsistence. However, the molecular underpinnings of how the parasite gains resources from its host remain largely unknown. Residing within a non-fusogenic parasitophorous vacuole (PV), the parasite must acquire resources across the limiting membrane of its replicative niche, which is decorated with parasite proteins including those secreted from dense granules. We discovered a role for the Endosomal Sorting Complex Required for Transport (ESCRT) machinery in host cytosolic protein uptake by T. gondii by disrupting host ESCRT function. We identified the transmembrane dense granule protein TgGRA14, which contains motifs homologous to the late domain motifs of HIV-1 Gag, as a candidate for the recruitment of the host ESCRT machinery to the PV membrane. Using an HIV-1 virus-like particle (VLP) release assay, we found that the motif-containing portion of TgGRA14 is sufficient to substitute for HIV-1 Gag late domain to mediate ESCRT-dependent VLP budding. We also show that TgGRA14 is proximal to and interacts with host ESCRT components and other dense granule proteins during infection. Furthermore, analysis of TgGRA14-deficient parasites revealed a marked reduction in ingestion of a host cytosolic protein compared to WT parasites. Thus, we propose a model in which T. gondii recruits the host ESCRT machinery to the PV where it can interact with TgGRA14 for the internalization of host cytosolic proteins across the PV membrane (PVM). These findings provide new insight into how T. gondii accesses contents of the host cytosol by exploiting a key pathway for vesicular budding and membrane scission.

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