1
|
Tang X, Liu Y, Wang J, Long T, Yee Mok BW, Huang Y, Peng Z, Jia Q, Liu C, So PK, Pui-Kam Tse S, Hei Ng C, Liu S, Sun F, Tang S, Yao ZP, Chen H, Guo Y. Identifications of novel host cell factors that interact with the receptor-binding domain of the SARS-CoV-2 spike protein. J Biol Chem 2024; 300:107390. [PMID: 38777146 PMCID: PMC11237930 DOI: 10.1016/j.jbc.2024.107390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Revised: 04/08/2024] [Accepted: 04/25/2024] [Indexed: 05/25/2024] Open
Abstract
SARS-CoV-2 entry into host cells is facilitated by the interaction between the receptor-binding domain of its spike protein (CoV2-RBD) and host cell receptor, ACE2, promoting viral membrane fusion. The virus also uses endocytic pathways for entry, but the mediating host factors remain largely unknown. It is also unknown whether mutations in the RBD of SARS-CoV-2 variants promote interactions with additional host factors to promote viral entry. Here, we used the GST pull-down approach to identify novel surface-located host factors that bind to CoV2-RBD. One of these factors, SH3BP4, regulates internalization of CoV2-RBD in an ACE2-independent but integrin- and clathrin-dependent manner and mediates SARS-CoV-2 pseudovirus entry, suggesting that SH3BP4 promotes viral entry via the endocytic route. Many of the identified factors, including SH3BP4, ADAM9, and TMEM2, show stronger affinity to CoV2-RBD than to RBD of the less infective SARS-CoV, suggesting SARS-CoV-2-specific utilization. We also found factors preferentially binding to the RBD of the SARS-CoV-2 Delta variant, potentially enhancing its entry. These data identify the repertoire of host cell surface factors that function in the events leading to the entry of SARS-CoV-2.
Collapse
Affiliation(s)
- Xiao Tang
- Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Metabolic Diseases, College of Life Sciences, Anhui Normal University, Wuhu, China; Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong SAR, China
| | - Yang Liu
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong SAR, China
| | - Jinhui Wang
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong SAR, China
| | - Teng Long
- Department of Microbiology, The University of Hong Kong, Hong Kong SAR, China; Centre for Virology, Vaccinology and Therapeutics Limited, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Bobo Wing Yee Mok
- Department of Microbiology, The University of Hong Kong, Hong Kong SAR, China; Centre for Virology, Vaccinology and Therapeutics Limited, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Yan Huang
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong SAR, China
| | - Ziqing Peng
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong SAR, China
| | - Qinyu Jia
- State Key Laboratory of Chemical Biology and Drug Discovery, Research Institute for Future Food, Research Centre for Chinese Medicine Innovation, and Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China
| | - Chengxi Liu
- State Key Laboratory of Chemical Biology and Drug Discovery, Research Institute for Future Food, Research Centre for Chinese Medicine Innovation, and Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China
| | - Pui-Kin So
- State Key Laboratory of Chemical Biology and Drug Discovery, Research Institute for Future Food, Research Centre for Chinese Medicine Innovation, and Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China
| | - Sirius Pui-Kam Tse
- State Key Laboratory of Chemical Biology and Drug Discovery, Research Institute for Future Food, Research Centre for Chinese Medicine Innovation, and Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China
| | - Cheuk Hei Ng
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong SAR, China
| | - Shiyi Liu
- Thrust of Bioscience and Biomedical Engineering, Hong Kong University of Science and Technology (Guangzhou), Guangzhou, China
| | - Fei Sun
- Department of Chemical and Biological Engineering, Hong Kong University of Science and Technology, Hong Kong SAR, China
| | - Shaojun Tang
- Thrust of Bioscience and Biomedical Engineering, Hong Kong University of Science and Technology (Guangzhou), Guangzhou, China
| | - Zhong-Ping Yao
- State Key Laboratory of Chemical Biology and Drug Discovery, Research Institute for Future Food, Research Centre for Chinese Medicine Innovation, and Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China
| | - Honglin Chen
- Department of Microbiology, The University of Hong Kong, Hong Kong SAR, China; Centre for Virology, Vaccinology and Therapeutics Limited, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Yusong Guo
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong SAR, China; Hong Kong University of Science and Technology, Shenzhen Research Institute, Shenzhen, China.
| |
Collapse
|
2
|
Tamilselvan E, Sotomayor M. CELSR1, a core planar cell polarity protein, features a weakly adhesive and flexible cadherin ectodomain. Structure 2024; 32:476-491.e5. [PMID: 38307021 DOI: 10.1016/j.str.2024.01.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2023] [Revised: 09/30/2023] [Accepted: 01/08/2024] [Indexed: 02/04/2024]
Abstract
Planar cell polarity (PCP), essential to multicellular developmental processes, arises when cells polarize and align across tissues. Central to PCP is CELSR1, an atypical cadherin featuring a long ectodomain with nine extracellular cadherin (EC) repeats, a membrane adjacent domain (MAD10), and several characteristic adhesion GPCR domains. Cell-based aggregation assays have demonstrated CELSR1's homophilic adhesive nature, but mechanistic details are missing. Here, we investigate the possible adhesive properties and structures of CELSR1 EC repeats. Our bead aggregation assays do not support strong adhesion by EC repeats alone. Consistently, EC1-4 only dimerizes at high concentration in solution. Crystal structures of human CELSR1 EC1-4 and EC4-7 reveal typical folds and a non-canonical linker between EC5 and EC6. Simulations and experiments using EC4-7 indicate flexibility at EC5-6, and solution experiments show EC7-MAD10-mediated dimerization. Our results suggest weak homophilic adhesion by CELSR1 cadherin repeats and provide mechanistic insights into the structural determinants of CELSR1 function.
Collapse
Affiliation(s)
- Elakkiya Tamilselvan
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA; Biophysics Program, The Ohio State University, Columbus, OH 43210, USA
| | - Marcos Sotomayor
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA; Biophysics Program, The Ohio State University, Columbus, OH 43210, USA.
| |
Collapse
|
3
|
Li T, Yang F, Heng Y, Zhou S, Wang G, Wang J, Wang J, Chen X, Yao ZP, Wu Z, Guo Y. TMED10 mediates the trafficking of insulin-like growth factor 2 along the secretory pathway for myoblast differentiation. Proc Natl Acad Sci U S A 2023; 120:e2215285120. [PMID: 37931110 PMCID: PMC10655563 DOI: 10.1073/pnas.2215285120] [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: 09/07/2022] [Accepted: 10/02/2023] [Indexed: 11/08/2023] Open
Abstract
The insulin-like growth factor 2 (IGF2) plays critical roles in cell proliferation, migration, differentiation, and survival. Despite its importance, the molecular mechanisms mediating the trafficking of IGF2 along the secretory pathway remain unclear. Here, we utilized a Retention Using Selective Hook system to analyze molecular mechanisms that regulate the secretion of IGF2. We found that a type I transmembrane protein, TMED10, is essential for the secretion of IGF2 and for differentiation of mouse myoblast C2C12 cells. Further analyses indicate that the residues 112-140 in IGF2 are important for the secretion of IGF2 and these residues directly interact with the GOLD domain of TMED10. We then reconstituted the release of IGF2 into COPII vesicles. This assay suggests that TMED10 mediates the packaging of IGF2 into COPII vesicles to be efficiently delivered to the Golgi. Moreover, TMED10 also mediates ER export of TGN-localized cargo receptor, sortilin, which subsequently mediates TGN export of IGF2. These analyses indicate that TMED10 is critical for IGF2 secretion by directly regulating ER export and indirectly regulating TGN export of IGF2, providing insights into trafficking of IGF2 for myoblast differentiation.
Collapse
Affiliation(s)
- Tiantian Li
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Feng Yang
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Youshan Heng
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Shaopu Zhou
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Gang Wang
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Jianying Wang
- State Key Laboratory of Chemical Biology and Drug Discovery, Research Institute for Future Food, Research Centre for Chinese Medicine Innovation, and Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hong Kong, China
| | - Jinhui Wang
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Xianwei Chen
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Zhong-Ping Yao
- State Key Laboratory of Chemical Biology and Drug Discovery, Research Institute for Future Food, Research Centre for Chinese Medicine Innovation, and Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hong Kong, China
- State Key Laboratory of Chinese Medicine and Molecular Pharmacology (Incubation) and Shenzhen Key Laboratory of Food Biological Safety Control, Hong Kong Polytechnic University, Shenzhen Research Institute, Shenzhen 518057, China
| | - Zhenguo Wu
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Yusong Guo
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong, China
- Hong Kong University of Science and Technology, Shenzhen Research Institute, Shenzhen 518057, China
- Thrust of Bioscience and Biomedical Engineering, Hong Kong University of Science and Technology, Guangzhou 511453, China
| |
Collapse
|
4
|
Cetera M, Sharan R, Hayward-Lara G, Phillips B, Biswas A, Halley M, Beall E, vonHoldt B, Devenport D. Region-specific reversal of epidermal planar polarity in the rosette fancy mouse. Development 2023; 150:dev202078. [PMID: 37622728 PMCID: PMC10499026 DOI: 10.1242/dev.202078] [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: 06/13/2023] [Accepted: 08/21/2023] [Indexed: 08/26/2023]
Abstract
The planar cell polarity (PCP) pathway collectively orients cells with respect to a body axis. Hair follicles of the murine epidermis provide a striking readout of PCP activity in their uniform alignment across the skin. Here, we characterize, from the molecular to tissue-scale, PCP establishment in the rosette fancy mouse, a natural variant with posterior-specific whorls in its fur, to understand how epidermal polarity is coordinated across the tissue. We find that rosette hair follicles emerge with reversed orientations specifically in the posterior region, creating a mirror image of epidermal polarity. The rosette trait is associated with a missense mutation in the core PCP gene Fzd6, which alters a consensus site for N-linked glycosylation, inhibiting its membrane localization. Unexpectedly, the Fzd6 trafficking defect does not block asymmetric localization of the other PCP proteins. Rather, the normally uniform axis of PCP asymmetry rotates where the PCP-directed cell movements that orient follicles are reversed, suggesting the PCP axis rotates 180°. Collectively, our multiscale analysis of epidermal polarity reveals PCP patterning can be regionally decoupled to produce posterior whorls in the rosette fancy mouse.
Collapse
Affiliation(s)
- Maureen Cetera
- Department of Genetics, Cell Biology and Development, University of Minnesota Twin Cities, Minneapolis, MN 55455, USA
| | - Rishabh Sharan
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08540, USA
| | | | - Brooke Phillips
- Department of Molecular Biology, Princeton University, Princeton, NJ 08540, USA
| | - Abhishek Biswas
- Department of Molecular Biology, Princeton University, Princeton, NJ 08540, USA
- Research Computing, Office of Information Technology, Princeton University, Princeton, NJ 08540, USA
| | - Madalene Halley
- Department of Genetics, Cell Biology and Development, University of Minnesota Twin Cities, Minneapolis, MN 55455, USA
| | - Evalyn Beall
- Department of Genetics, Cell Biology and Development, University of Minnesota Twin Cities, Minneapolis, MN 55455, USA
| | - Bridgett vonHoldt
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08540, USA
| | - Danelle Devenport
- Department of Molecular Biology, Princeton University, Princeton, NJ 08540, USA
| |
Collapse
|
5
|
Cetera M, Sharan R, Hayward-Lara G, Phillips B, Biswas A, Halley M, Beall E, vonHoldt B, Devenport D. Region-specific reversal of epidermal planar polarity in the fancy rosette mouse. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.27.550849. [PMID: 37546950 PMCID: PMC10402159 DOI: 10.1101/2023.07.27.550849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
The planar cell polarity (PCP) pathway collectively orients thousands of cells with respect to a body axis to direct cellular behaviors that are essential for embryonic morphogenesis. Hair follicles of the murine epidermis provide a striking readout of PCP activity in their uniform alignment along the entire skin surface. Here, we characterize, from the molecular to tissue-scale, PCP establishment in the rosette fancy mouse, a natural variant with posterior-specific whorls in its fur, to understand how epidermal polarity is coordinated across the tissue. We find that embryonic hair follicles of rosette mutants emerge with reversed orientations specifically in the posterior region, creating a mirror image of epidermal polarity. The rosette trait is associated with a missense mutation in the core PCP gene Fzd6 , which alters a consensus site for N-linked glycosylation and inhibits its membrane localization. Unexpectedly, this defect in Fzd6 trafficking, observed across the entire dorsal epidermis, does not interfere with the ability of other core PCP proteins to localize asymmetrically. Rather, the normally uniform axis of PCP asymmetry is disrupted and rotated in the posterior region such that polarity is reflected on either side of a transition zone. The result is a reversal of polarized cell movements that orient nascent follicles, specifically in the posterior of the embryo. Collectively, our multiscale analysis of epidermal polarity reveals PCP patterning can be regionally decoupled to produce the unique posterior whorls of the fancy rosette mouse. Summary Region-specific rotation of the Planar Cell Polarity axis reverses posterior hair follicles in the fancy rosette mouse.
Collapse
|
6
|
Wang M, Wang J, Guo Y. Reconstitution of Vesicle Budding from the TGN and Immunoisolation of Vesicles Enriched with a Specific Cargo Client. Methods Mol Biol 2022; 2557:289-302. [PMID: 36512223 DOI: 10.1007/978-1-0716-2639-9_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The trans-Golgi network (TGN) is an important cargo sorting station in the secretory pathway. To reveal insights into protein sorting at the TGN, it is important to develop an assay to quantify the efficiency of cargo capture. Here, we describe an experimental approach to reconstitute the packaging of cargo proteins into vesicles at the TGN in vitro. We also describe an experimental approach to immunoisolate vesicles enriched with a specific transmembrane cargo client from the in vitro vesicle formation assay. These assays provide robust tools to directly measure the enrichment of cargo proteins into TGN-derived vesicles and to reveal novel factors that regulate TGN export process.
Collapse
Affiliation(s)
- Mo Wang
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Jinhui Wang
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Yusong Guo
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong, China. .,Hong Kong University of Science and Technology Shenzhen Research Institute, Shenzhen, China. .,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China.
| |
Collapse
|
7
|
Tang X, Wang T, Guo Y. Export of polybasic motif-containing secretory proteins BMP8A and SFRP1 from the endoplasmic reticulum is regulated by surfeit locus protein 4. J Biol Chem 2022; 298:102687. [PMID: 36370847 PMCID: PMC9731852 DOI: 10.1016/j.jbc.2022.102687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 10/29/2022] [Accepted: 11/01/2022] [Indexed: 11/11/2022] Open
Abstract
In the conventional secretory pathway, cargo receptors play important roles in exporting newly synthesized secretory proteins from the endoplasmic reticulum (ER). We previously showed that a cargo receptor, surfeit locus protein 4 (SURF4), promotes ER export of a soluble signaling molecule, sonic hedgehog, via recognizing the polybasic residues within its Cardin-Weintraub motif. In addition to sonic hedgehog, we found 30 more secretory proteins containing the polybasic motif (K/R)(K/R)(K/R)XX(K/R)(K/R), but whether SURF4 plays a general role in mediating ER export of these secretory proteins is unclear. Here, we analyzed the trafficking of four of these secretory proteins: desert hedgehog, Indian hedgehog, bone morphogenetic protein 8A (BMP8A), and secreted frizzled-related protein 1 (SFRP1). We found that the polybasic motifs contained in these cargo proteins are important for their ER export. Further analyses indicated that the polybasic motifs of BMP8A and SFRP1 interact with the triacidic motif on the predicted first luminal domain of SURF4. These interactions with SURF4 are essential and sufficient for the ER-to-Golgi trafficking of BMP8A and SFRP1. Moreover, we demonstrated that SURF4 localizes at a subpopulation of ER exit sites to regulate the ER export of its clients. Taken together, these results suggest that SURF4 is recruited to specific ER exit sites and plays a general role in capturing polybasic motif-containing secretory cargo proteins through electrostatic interactions.
Collapse
Affiliation(s)
- Xiao Tang
- College of Life Sciences, Anhui Normal University, Wuhu, Anhui, China,Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Tingxuan Wang
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Yusong Guo
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong, China,Hong Kong University of Science and Technology Shenzhen Research Institute, Shenzhen, China,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China,For correspondence: Yusong Guo
| |
Collapse
|
8
|
A SURF4-to-proteoglycan relay mechanism that mediates the sorting and secretion of a tagged variant of sonic hedgehog. Proc Natl Acad Sci U S A 2022; 119:e2113991119. [PMID: 35271396 PMCID: PMC8931250 DOI: 10.1073/pnas.2113991119] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
SignificanceSonic Hedgehog (Shh) is a key signaling molecule that plays important roles in embryonic patterning, cell differentiation, and organ development. Although fundamentally important, the molecular mechanisms that regulate secretion of newly synthesized Shh are still unclear. Our study reveals a role for the cargo receptor, SURF4, in facilitating export of Shh from the endoplasmic reticulum (ER) via a ER export signal. In addition, our study provides evidence suggesting that proteoglycans promote the dissociation of SURF4 from Shh at the Golgi, suggesting a SURF4-to-proteoglycan relay mechanism. These analyses provide insight into an important question in cell biology: how do cargo receptors capture their clients in one compartment, then disengage at their destination?
Collapse
|
9
|
Zhang N, Zabotina OA. Critical Determinants in ER-Golgi Trafficking of Enzymes Involved in Glycosylation. PLANTS (BASEL, SWITZERLAND) 2022; 11:plants11030428. [PMID: 35161411 PMCID: PMC8840164 DOI: 10.3390/plants11030428] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 01/31/2022] [Accepted: 02/01/2022] [Indexed: 05/03/2023]
Abstract
All living cells generate structurally complex and compositionally diverse spectra of glycans and glycoconjugates, critical for organismal evolution, development, functioning, defense, and survival. Glycosyltransferases (GTs) catalyze the glycosylation reaction between activated sugar and acceptor substrate to synthesize a wide variety of glycans. GTs are distributed among more than 130 gene families and are involved in metabolic processes, signal pathways, cell wall polysaccharide biosynthesis, cell development, and growth. Glycosylation mainly takes place in the endoplasmic reticulum (ER) and Golgi, where GTs and glycosidases involved in this process are distributed to different locations of these compartments and sequentially add or cleave various sugars to synthesize the final products of glycosylation. Therefore, delivery of these enzymes to the proper locations, the glycosylation sites, in the cell is essential and involves numerous secretory pathway components. This review presents the current state of knowledge about the mechanisms of protein trafficking between ER and Golgi. It describes what is known about the primary components of protein sorting machinery and trafficking, which are recognition sites on the proteins that are important for their interaction with the critical components of this machinery.
Collapse
|
10
|
Li T, Guo Y. ADP-Ribosylation Factor Family of Small GTP-Binding Proteins: Their Membrane Recruitment, Activation, Crosstalk and Functions. Front Cell Dev Biol 2022; 10:813353. [PMID: 35186926 PMCID: PMC8850633 DOI: 10.3389/fcell.2022.813353] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Accepted: 01/14/2022] [Indexed: 11/13/2022] Open
Abstract
Members of the ADP-ribosylation factor (ARF) family of guanine-nucleotide binding proteins play critical roles in various cellular processes, especially in regulating the secretory, and endocytic pathways. The fidelity of intracellular vesicular trafficking depends on proper activations and precise subcellular distributions of ARF family proteins regulated by guanine nucleotide exchange factors (GEFs) and GTPase-activating proteins (GAPs). Here we review recent progress in understanding the membrane recruitment, activation, crosstalk, and functions of ARF family proteins.
Collapse
Affiliation(s)
- Tiantian Li
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Kowloon, Hong Kong SAR, China
| | - Yusong Guo
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Kowloon, Hong Kong SAR, China
- Hong Kong University of Science and Technology, Shenzhen Research Institute, Shenzhen, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China
- *Correspondence: Yusong Guo,
| |
Collapse
|
11
|
An in vitro vesicle formation assay reveals cargo clients and factors that mediate vesicular trafficking. Proc Natl Acad Sci U S A 2021; 118:2101287118. [PMID: 34433667 PMCID: PMC8536394 DOI: 10.1073/pnas.2101287118] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Protein sorting in the secretory pathway is a fundamentally important cellular process, but the clients of a specific cargo sorting machinery remains largely underinvestigated. Here, utilizing a vesicle formation assay to profile proteins associated with vesicles, we identified cytosolic proteins that are associated with vesicle membranes in a GTP-dependent manner or that interact with GTP-bound Sar1A. We found that two of them, FAM84B and PRRC1, regulate anterograde trafficking. Moreover, we revealed specific clients of two export adaptors, SURF4 and ERGIC53. These analyses demonstrate that our approach is powerful to identify factors that regulate vesicular trafficking and to uncover clients of specific cargo receptors, providing a robust method to reveal insights into the secretory pathway. The fidelity of protein transport in the secretory pathway relies on the accurate sorting of proteins to their correct destinations. To deepen our understanding of the underlying molecular mechanisms, it is important to develop a robust approach to systematically reveal cargo proteins that depend on specific sorting machinery to be enriched into transport vesicles. Here, we used an in vitro assay that reconstitutes packaging of human cargo proteins into vesicles to quantify cargo capture. Quantitative mass spectrometry (MS) analyses of the isolated vesicles revealed cytosolic proteins that are associated with vesicle membranes in a GTP-dependent manner. We found that two of them, FAM84B (also known as LRAT domain containing 2 or LRATD2) and PRRC1, contain proline-rich domains and regulate anterograde trafficking. Further analyses revealed that PRRC1 is recruited to endoplasmic reticulum (ER) exit sites, interacts with the inner COPII coat, and its absence increases membrane association of COPII. In addition, we uncovered cargo proteins that depend on GTP hydrolysis to be captured into vesicles. Comparing control cells with cells depleted of the cargo receptors, SURF4 or ERGIC53, we revealed specific clients of each of these two export adaptors. Our results indicate that the vesicle formation assay in combination with quantitative MS analysis is a robust and powerful tool to uncover novel factors that mediate vesicular trafficking and to uncover cargo clients of specific cellular factors.
Collapse
|
12
|
Endoplasmic reticulum composition and form: Proteins in and out. Curr Opin Cell Biol 2021; 71:1-6. [PMID: 33611096 DOI: 10.1016/j.ceb.2021.01.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 01/18/2021] [Accepted: 01/19/2021] [Indexed: 02/07/2023]
Abstract
The endoplasmic reticulum (ER) is the main harbor for newly synthesized proteins in eukaryotic cells. Through a continuous membrane network of sheets and tubules, the ER hosts secretory proteins, integral membrane proteins, and luminal proteins of the endomembrane system. These proteins are translated by ribosomes outside the ER and require subsequent integration into or translocation across the lipid bilayer of the ER. They are then modified post-translationally and folded in the ER. Some of these proteins are packaged into coat protein complex II-coated vesicles for export. Here, we review recent advances in understanding the mechanism of protein translocation and transmembrane domain insertion in the ER, summarize new insights into selective cargo packaging, and discuss the roles of ER morphological dynamics in these processes.
Collapse
|