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Ragagnin AMG, Sundaramoorthy V, Farzana F, Gautam S, Saravanabavan S, Takalloo Z, Mehta P, Do-Ha D, Parakh S, Shadfar S, Hunter J, Vidal M, Jagaraj CJ, Brocardo M, Konopka A, Yang S, Rayner SL, Williams KL, Blair IP, Chung RS, Lee A, Ooi L, Atkin JD. ALS/FTD-associated mutation in cyclin F inhibits ER-Golgi trafficking, inducing ER stress, ERAD and Golgi fragmentation. Sci Rep 2023; 13:20467. [PMID: 37993492 PMCID: PMC10665471 DOI: 10.1038/s41598-023-46802-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 11/05/2023] [Indexed: 11/24/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a severely debilitating neurodegenerative condition that is part of the same disease spectrum as frontotemporal dementia (FTD). Mutations in the CCNF gene, encoding cyclin F, are present in both sporadic and familial ALS and FTD. However, the pathophysiological mechanisms underlying neurodegeneration remain unclear. Proper functioning of the endoplasmic reticulum (ER) and Golgi apparatus compartments is essential for normal physiological activities and to maintain cellular viability. Here, we demonstrate that ALS/FTD-associated variant cyclin FS621G inhibits secretory protein transport from the ER to Golgi apparatus, by a mechanism involving dysregulation of COPII vesicles at ER exit sites. Consistent with this finding, cyclin FS621G also induces fragmentation of the Golgi apparatus and activates ER stress, ER-associated degradation, and apoptosis. Induction of Golgi fragmentation and ER stress were confirmed with a second ALS/FTD variant cyclin FS195R, and in cortical primary neurons. Hence, this study provides novel insights into pathogenic mechanisms associated with ALS/FTD-variant cyclin F, involving perturbations to both secretory protein trafficking and ER-Golgi homeostasis.
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Affiliation(s)
- Audrey M G Ragagnin
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Vinod Sundaramoorthy
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Fabiha Farzana
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Shashi Gautam
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Sayanthooran Saravanabavan
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Zeinab Takalloo
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Prachi Mehta
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Dzung Do-Ha
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Northfields Avenue, Wollongong, NSW, 2522, Australia
| | - Sonam Parakh
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Sina Shadfar
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Julie Hunter
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Marta Vidal
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Cyril J Jagaraj
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Mariana Brocardo
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Anna Konopka
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Shu Yang
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Stephanie L Rayner
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Kelly L Williams
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Ian P Blair
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Roger S Chung
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Albert Lee
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Lezanne Ooi
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Northfields Avenue, Wollongong, NSW, 2522, Australia
| | - Julie D Atkin
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, 2109, Australia.
- La Trobe Institute for Molecular Science, La Trobe University, Bundoora, Melbourne, VIC, 3086, Australia.
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2
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Tanaka T, Moriya K, Tsunenaga M, Yanagawa T, Morita H, Minowa T, Tagawa YI, Hanagata N, Inagaki Y, Ikoma T. Visualized procollagen Iα1 demonstrates the intracellular processing of propeptides. Life Sci Alliance 2022; 5:5/5/e202101060. [PMID: 35181633 PMCID: PMC8860094 DOI: 10.26508/lsa.202101060] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 01/26/2022] [Accepted: 01/26/2022] [Indexed: 12/26/2022] Open
Abstract
Procollagen Iα1 with two tags reveals the different fates of processed propeptides, the rate-limiting step in collagen secretion, and a link between defects in intracellular processing and diseases. The processing of type I procollagen is essential for fibril formation; however, the steps involved remain controversial. We constructed a live cell imaging system by inserting fluorescent proteins into type I pre-procollagen α1. Based on live imaging and immunostaining, the C-propeptide is intracellularly cleaved at the perinuclear region, including the endoplasmic reticulum, and subsequently accumulates at the upside of the cell. The N-propeptide is also intracellularly cleaved, but is transported with the repeating structure domain of collagen into the extracellular region. This system makes it possible to detect relative increases and decreases in collagen secretion in a high-throughput manner by assaying fluorescence in the culture medium, and revealed that the rate-limiting step for collagen secretion occurs after the synthesis of procollagen. In the present study, we identified a defect in procollagen processing in activated hepatic stellate cells, which secrete aberrant collagen fibrils. The results obtained demonstrated the intracellular processing of type I procollagen, and revealed a link between dysfunctional processing and diseases such as hepatic fibrosis.
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Affiliation(s)
- Toshiaki Tanaka
- School of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsuta, Yokohama, Japan
| | - Koji Moriya
- School of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsuta, Yokohama, Japan
| | - Makoto Tsunenaga
- Shiseido Global Innovation Center, 1-2-11 Takashima, Yokohama, Japan
| | - Takayo Yanagawa
- School of Medicine, Tokai University, 143 Shimo-kasuya, Isehara, Japan
| | - Hiromi Morita
- Nanotechnology Innovation Station, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Japan
| | - Takashi Minowa
- Nanotechnology Innovation Station, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Japan
| | - Yoh-Ichi Tagawa
- School of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsuta, Yokohama, Japan
| | - Nobutaka Hanagata
- Nanotechnology Innovation Station, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Japan
| | - Yutaka Inagaki
- School of Medicine, Tokai University, 143 Shimo-kasuya, Isehara, Japan
| | - Toshiyuki Ikoma
- School of Materials and Chemical Technology, Tokyo Institute of Technology, Tokyo, Japan
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3
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Moreira DDP, Suzuki AM, Silva ALTE, Varella-Branco E, Meneghetti MCZ, Kobayashi GS, Fogo M, Ferrari MDFR, Cardoso RR, Lourenço NCV, Griesi-Oliveira K, Zachi EC, Bertola DR, Weinmann KDS, de Lima MA, Nader HB, Sertié AL, Passos-Bueno MR. Neuroprogenitor Cells From Patients With TBCK Encephalopathy Suggest Deregulation of Early Secretory Vesicle Transport. Front Cell Neurosci 2022; 15:803302. [PMID: 35095425 PMCID: PMC8793280 DOI: 10.3389/fncel.2021.803302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 12/15/2021] [Indexed: 11/13/2022] Open
Abstract
Biallelic pathogenic variants in TBCK cause encephaloneuropathy, infantile hypotonia with psychomotor retardation, and characteristic facies 3 (IHPRF3). The molecular mechanisms underlying its neuronal phenotype are largely unexplored. In this study, we reported two sisters, who harbored biallelic variants in TBCK and met diagnostic criteria for IHPRF3. We provided evidence that TBCK may play an important role in the early secretory pathway in neuroprogenitor cells (iNPC) differentiated from induced pluripotent stem cells (iPSC). Lack of functional TBCK protein in iNPC is associated with impaired endoplasmic reticulum-to-Golgi vesicle transport and autophagosome biogenesis, as well as altered cell cycle progression and severe impairment in the capacity of migration. Alteration in these processes, which are crucial for neurogenesis, neuronal migration, and cytoarchitecture organization, may represent an important causative mechanism of both neurodevelopmental and neurodegenerative phenotypes observed in IHPRF3. Whether reduced mechanistic target of rapamycin (mTOR) signaling is secondary to impaired TBCK function over other secretory transport regulators still needs further investigation.
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Affiliation(s)
- Danielle de Paula Moreira
- Centro de Pesquisas Sobre o Genoma Humano e Células-Tronco, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
| | - Angela May Suzuki
- Centro de Pesquisas Sobre o Genoma Humano e Células-Tronco, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
| | | | - Elisa Varella-Branco
- Centro de Pesquisas Sobre o Genoma Humano e Células-Tronco, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
| | | | - Gerson Shigeru Kobayashi
- Centro de Pesquisas Sobre o Genoma Humano e Células-Tronco, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
| | - Mariana Fogo
- Centro de Pesquisas Sobre o Genoma Humano e Células-Tronco, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
- Instituto de Ensino e Pesquisa Albert Einstein, Albert Einstein Hospital, São Paulo, Brazil
| | | | - Rafaela Regina Cardoso
- Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
| | - Naila Cristina Vilaça Lourenço
- Centro de Pesquisas Sobre o Genoma Humano e Células-Tronco, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
| | - Karina Griesi-Oliveira
- Centro de Pesquisas Sobre o Genoma Humano e Células-Tronco, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
- Instituto de Ensino e Pesquisa Albert Einstein, Albert Einstein Hospital, São Paulo, Brazil
| | - Elaine Cristina Zachi
- Centro de Pesquisas Sobre o Genoma Humano e Células-Tronco, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
| | - Débora Romeo Bertola
- Centro de Pesquisas Sobre o Genoma Humano e Células-Tronco, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
- Instituto da Criança do Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Karina de Souza Weinmann
- Centro de Pesquisas Sobre o Genoma Humano e Células-Tronco, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
| | - Marcelo Andrade de Lima
- Departamento de Bioquímica, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Helena Bonciani Nader
- Departamento de Bioquímica, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Andrea Laurato Sertié
- Instituto de Ensino e Pesquisa Albert Einstein, Albert Einstein Hospital, São Paulo, Brazil
| | - Maria Rita Passos-Bueno
- Centro de Pesquisas Sobre o Genoma Humano e Células-Tronco, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
- *Correspondence: Maria Rita Passos-Bueno,
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Molecular basis of ubiquitin-specific protease 8 autoinhibition by the WW-like domain. Commun Biol 2021; 4:1272. [PMID: 34750505 PMCID: PMC8576004 DOI: 10.1038/s42003-021-02802-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 10/22/2021] [Indexed: 12/26/2022] Open
Abstract
Ubiquitin-specific protease 8 (USP8) is a deubiquitinating enzyme involved in multiple membrane trafficking pathways. The enzyme activity is inhibited by binding to 14-3-3 proteins. Mutations in the 14-3-3-binding motif in USP8 are related to Cushing’s disease. However, the molecular basis of USP8 activity regulation remains unclear. This study identified amino acids 645–684 of USP8 as an autoinhibitory region, which might interact with the catalytic USP domain, as per the results of pull-down and single-molecule FRET assays performed in this study. In silico modelling indicated that the region forms a WW-like domain structure, plugs the catalytic cleft, and narrows the entrance to the ubiquitin-binding pocket. Furthermore, 14-3-3 inhibited USP8 activity partly by enhancing the interaction between the WW-like and USP domains. These findings provide the molecular basis of USP8 autoinhibition via the WW-like domain. Moreover, they suggest that the release of autoinhibition may underlie Cushing’s disease due to USP8 mutations. In order to advance our understanding of the regulation of Ubiquitin-specific protease 8 (USP8), which is known to play a role in Cushing’s Disease, Kakihara et al identify and characterise amino acids 645–684 of USP8, which serve as an autoinhibitory region. Their pull-down and single-molecule FRET analysis, as well as in silico modelling, suggest that the release of USP8 autoinhibition may underlie Cushing’s disease.
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5
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Bisnett BJ, Condon BM, Lamb CH, Georgiou GR, Boyce M. Export Control: Post-transcriptional Regulation of the COPII Trafficking Pathway. Front Cell Dev Biol 2021; 8:618652. [PMID: 33511128 PMCID: PMC7835409 DOI: 10.3389/fcell.2020.618652] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Accepted: 12/14/2020] [Indexed: 11/13/2022] Open
Abstract
The coat protein complex II (COPII) mediates forward trafficking of protein and lipid cargoes from the endoplasmic reticulum. COPII is an ancient and essential pathway in all eukaryotes and COPII dysfunction underlies a range of human diseases. Despite this broad significance, major aspects of COPII trafficking remain incompletely understood. For example, while the biochemical features of COPII vesicle formation are relatively well characterized, much less is known about how the COPII system dynamically adjusts its activity to changing physiologic cues or stresses. Recently, post-transcriptional mechanisms have emerged as a major mode of COPII regulation. Here, we review the current literature on how post-transcriptional events, and especially post-translational modifications, govern the COPII pathway.
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Affiliation(s)
- Brittany J Bisnett
- Department of Biochemistry, Duke University School of Medicine, Durham, NC, United States
| | - Brett M Condon
- Department of Biochemistry, Duke University School of Medicine, Durham, NC, United States
| | - Caitlin H Lamb
- Department of Biochemistry, Duke University School of Medicine, Durham, NC, United States
| | - George R Georgiou
- Department of Biochemistry, Duke University School of Medicine, Durham, NC, United States
| | - Michael Boyce
- Department of Biochemistry, Duke University School of Medicine, Durham, NC, United States
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6
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Blondelle J, Marrocco V, Clark M, Desmond P, Myers S, Nguyen J, Wright M, Bremner S, Pierantozzi E, Ward S, Estève E, Sorrentino V, Ghassemian M, Lange S. Murine obscurin and Obsl1 have functionally redundant roles in sarcolemmal integrity, sarcoplasmic reticulum organization, and muscle metabolism. Commun Biol 2019; 2:178. [PMID: 31098411 PMCID: PMC6509138 DOI: 10.1038/s42003-019-0405-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Accepted: 03/28/2019] [Indexed: 12/19/2022] Open
Abstract
Biological roles of obscurin and its close homolog Obsl1 (obscurin-like 1) have been enigmatic. While obscurin is highly expressed in striated muscles, Obsl1 is found ubiquitously. Accordingly, obscurin mutations have been linked to myopathies, whereas mutations in Obsl1 result in 3M-growth syndrome. To further study unique and redundant functions of these closely related proteins, we generated and characterized Obsl1 knockouts. Global Obsl1 knockouts are embryonically lethal. In contrast, skeletal muscle-specific Obsl1 knockouts show a benign phenotype similar to obscurin knockouts. Only deletion of both proteins and removal of their functional redundancy revealed their roles for sarcolemmal stability and sarcoplasmic reticulum organization. To gain unbiased insights into changes to the muscle proteome, we analyzed tibialis anterior and soleus muscles by mass spectrometry, uncovering additional changes to the muscle metabolism. Our analyses suggest that all obscurin protein family members play functions for muscle membrane systems.
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Affiliation(s)
- Jordan Blondelle
- Division of Cardiology, School of Medicine, University of California, San Diego, 92093 CA USA
| | - Valeria Marrocco
- Division of Cardiology, School of Medicine, University of California, San Diego, 92093 CA USA
| | - Madison Clark
- Division of Cardiology, School of Medicine, University of California, San Diego, 92093 CA USA
| | - Patrick Desmond
- Division of Cardiology, School of Medicine, University of California, San Diego, 92093 CA USA
| | - Stephanie Myers
- Division of Cardiology, School of Medicine, University of California, San Diego, 92093 CA USA
| | - Jim Nguyen
- Division of Cardiology, School of Medicine, University of California, San Diego, 92093 CA USA
| | - Matthew Wright
- Division of Cardiology, School of Medicine, University of California, San Diego, 92093 CA USA
| | - Shannon Bremner
- Department of Orthopedic Surgery, School of Medicine, University of California, San Diego, 92093 CA USA
| | - Enrico Pierantozzi
- Molecular Medicine Section, Department of Molecular and Developmental Medicine, University of Siena, Siena, 53100 Italy
| | - Samuel Ward
- Department of Orthopedic Surgery, School of Medicine, University of California, San Diego, 92093 CA USA
| | - Eric Estève
- Division of Cardiology, School of Medicine, University of California, San Diego, 92093 CA USA
- Université Grenoble Alpes, HP2, Grenoble, 38706 France
| | - Vincenzo Sorrentino
- Molecular Medicine Section, Department of Molecular and Developmental Medicine, University of Siena, Siena, 53100 Italy
| | - Majid Ghassemian
- Department of Chemistry and Biochemistry, University of California, San Diego, 92093 CA USA
| | - Stephan Lange
- Division of Cardiology, School of Medicine, University of California, San Diego, 92093 CA USA
- Wallenberg Laboratory, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg, Gothenburg, 413 45 Sweden
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Aridor M. COPII gets in shape: Lessons derived from morphological aspects of early secretion. Traffic 2018; 19:823-839. [DOI: 10.1111/tra.12603] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Revised: 06/26/2018] [Accepted: 07/04/2018] [Indexed: 12/13/2022]
Affiliation(s)
- Meir Aridor
- Department of Cell Biology; University of Pittsburgh School of Medicine; Pittsburgh Pennsylvania
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8
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McCaughey J, Stephens DJ. COPII-dependent ER export in animal cells: adaptation and control for diverse cargo. Histochem Cell Biol 2018; 150:119-131. [PMID: 29916038 PMCID: PMC6096569 DOI: 10.1007/s00418-018-1689-2] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/06/2018] [Indexed: 12/31/2022]
Abstract
The export of newly synthesized proteins from the endoplasmic reticulum is fundamental to the ongoing maintenance of cell and tissue structure and function. After co-translational translocation into the ER, proteins destined for downstream intracellular compartments or secretion from the cell are sorted and packaged into transport vesicles by the COPII coat protein complex. The fundamental discovery and characterization of the pathway has now been augmented by a greater understanding of the role of COPII in diverse aspects of cell function. We now have a deep understanding of how COPII contributes to the trafficking of diverse cargoes including extracellular matrix molecules, developmental signalling proteins, and key metabolic factors such as lipoproteins. Structural and functional studies have shown that the COPII coat is both highly flexible and subject to multiple modes of regulation. This has led to new discoveries defining roles of COPII in development, autophagy, and tissue organization. Many of these newly emerging features of the canonical COPII pathway are placed in a context of procollagen secretion because of the fundamental interest in how a coat complex that typically generates 80-nm transport vesicles can package a cargo reported to be over 300 nm. Here we review the current understanding of COPII and assess the current consensus on its role in packaging diverse cargo proteins.
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Affiliation(s)
- Janine McCaughey
- Cell Biology Laboratories, School of Biochemistry, University Walk, University of Bristol, Bristol, BS8 1TD, UK
| | - David J Stephens
- Cell Biology Laboratories, School of Biochemistry, University Walk, University of Bristol, Bristol, BS8 1TD, UK.
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