1
|
Kasberg W, Luong P, Hanna MG, Minushkin K, Tsao A, Shankar R, Block S, Audhya A. The Sar1 GTPase is dispensable for COPII-dependent cargo export from the ER. Cell Rep 2023; 42:112635. [PMID: 37300835 PMCID: PMC10592460 DOI: 10.1016/j.celrep.2023.112635] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 04/21/2023] [Accepted: 05/25/2023] [Indexed: 06/12/2023] Open
Abstract
Coat protein complex II (COPII) plays an integral role in the packaging of secretory cargoes within membrane-enclosed transport carriers that leave the endoplasmic reticulum (ER) from discrete subdomains. Lipid bilayer remodeling necessary for this process is driven initially by membrane penetration mediated by the Sar1 GTPase and further stabilized by assembly of a multilayered complex of several COPII proteins. However, the relative contributions of these distinct factors to transport carrier formation and protein trafficking remain unclear. Here, we demonstrate that anterograde cargo transport from the ER continues in the absence of Sar1, although the efficiency of this process is dramatically reduced. Specifically, secretory cargoes are retained nearly five times longer at ER subdomains when Sar1 is depleted, but they ultimately remain capable of being translocated to the perinuclear region of cells. Taken together, our findings highlight alternative mechanisms by which COPII promotes transport carrier biogenesis.
Collapse
Affiliation(s)
- William Kasberg
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53706, USA
| | - Peter Luong
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53706, USA
| | - Michael G Hanna
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53706, USA
| | - Kayla Minushkin
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53706, USA
| | - Annabelle Tsao
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53706, USA
| | - Raakhee Shankar
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53706, USA
| | - Samuel Block
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53706, USA
| | - Anjon Audhya
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53706, USA.
| |
Collapse
|
2
|
Kasberg W, Luong P, Swift KA, Audhya A. Nutrient deprivation alters the rate of COPII coat assembly to tune secretory protein transport. Res Sq 2023:rs.3.rs-2652351. [PMID: 36993182 PMCID: PMC10055522 DOI: 10.21203/rs.3.rs-2652351/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Co-assembly of the multilayered coat protein complex II (COPII) with the Sari GTPase at subdomains of the endoplasmic reticulum (ER) enables secretory cargoes to be concentrated efficiently within nascent transport intermediates, which subsequently deliver their contents to ER-Golgi intermediate compartments. Here, we define the spatiotemporal accumulation of native COPII subunits and secretory cargoes at ER subdomains under differing nutrient availability conditions using a combination of CRISPR/Cas9-mediated genome editing and live cell imaging. Our findings demonstrate that the rate of inner COPII coat assembly serves as a determinant for the pace of cargo export, irrespective of COPII subunit expression levels. Moreover, increasing inner COPII coat assembly kinetics is sufficient to rescue cargo trafficking deficits caused by acute nutrient limitation in a manner dependent on Sar1 GTPase activity. Our findings are consistent with a model in which the rate of inner COPII coat formation acts as an important control point to regulate cargo export from the ER.
Collapse
Affiliation(s)
- William Kasberg
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53706, USA
| | - Peter Luong
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53706, USA
| | - Kevin A. Swift
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53706, USA
| | - Anjon Audhya
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53706, USA
| |
Collapse
|
3
|
Chen S, Wei X, Zhang X, Yao M, Qiu Z, Chen L, Zhang L. Supplementation with Tex261 provides a possible preventive treatment for hypoxic pulmonary artery hypertension. Front Pharmacol 2022; 13:1028058. [PMID: 36408272 PMCID: PMC9669906 DOI: 10.3389/fphar.2022.1028058] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 10/19/2022] [Indexed: 10/28/2023] Open
Abstract
Objectives: Pulmonary artery hypertension (PAH) is a serious disease for which there is no effective treatment. Its pathogenesis is complex and has not yet been clarified. Tex261 is a protein-coding gene whose functional enrichment nodes include the transporter activity of COP II. However, the role of Tex261 in PAH remains unknown. Methods: Sugen5416/Hypoxic PAH models were established, and pulmonary arteries (PAs) were isolated for proteomic sequencing. The binding sites between Hif-1α and Tex261 were verified by dual-luciferase reporter gene assay. Cell proliferation was detected by MTS and EdU assays. For determination of the preventive and therapeutic effects of Tex261, intratracheal instillation of adeno-associated virus (AVV6) with Tex261 vectors was performed. Results: Tex261 was screened according to the proteomic sequencing data. Hif-1α inhibited Tex261 promoter activity under hypoxia. Decreased Tex261 expression promoted PASMC proliferation. Tex261 regulated Sec23 via the Ndrg1-mediated Akt pathway. Tex261 overexpression improved the pressure and vessel remodeling of PAs induced by Sugen5416/hypoxia. Conclusion: Hypoxia suppressed Tex261 expression through Hif-1α activation. The decreased Tex261 could promote Ndrg1 and depress Akt activity and then inhibit Sec23 activity, which leads to cell proliferation and vessel remodeling. Elevated Tex261 has some preventive and therapeutic effects on rats with PAH.
Collapse
Affiliation(s)
- Shaokun Chen
- Department of Cardiac Surgery, Fujian Medical University Union Hospital, Fuzhou, China
- Department of Pathophysiology, The School of Basic Medical Sciences, The Key Laboratory of Fujian Province Universities on Ion Channel and Signal Transduction in Cardiovascular Diseases, Fuzhou, China
| | - Xiaozhen Wei
- Department of Cardiac Surgery, Fujian Medical University Union Hospital, Fuzhou, China
- Department of Pathophysiology, The School of Basic Medical Sciences, The Key Laboratory of Fujian Province Universities on Ion Channel and Signal Transduction in Cardiovascular Diseases, Fuzhou, China
| | - Xu Zhang
- Department of Cardiac Surgery, Fujian Medical University Union Hospital, Fuzhou, China
- Department of Pathophysiology, The School of Basic Medical Sciences, The Key Laboratory of Fujian Province Universities on Ion Channel and Signal Transduction in Cardiovascular Diseases, Fuzhou, China
| | - Mengge Yao
- Department of Cardiac Surgery, Fujian Medical University Union Hospital, Fuzhou, China
- Department of Pathophysiology, The School of Basic Medical Sciences, The Key Laboratory of Fujian Province Universities on Ion Channel and Signal Transduction in Cardiovascular Diseases, Fuzhou, China
| | - Zhihuang Qiu
- Department of Cardiac Surgery, Fujian Medical University Union Hospital, Fuzhou, China
| | - Liangwan Chen
- Department of Cardiac Surgery, Fujian Medical University Union Hospital, Fuzhou, China
| | - Li Zhang
- Department of Cardiac Surgery, Fujian Medical University Union Hospital, Fuzhou, China
- Department of Pathophysiology, The School of Basic Medical Sciences, The Key Laboratory of Fujian Province Universities on Ion Channel and Signal Transduction in Cardiovascular Diseases, Fuzhou, China
| |
Collapse
|
4
|
Vélez AM, Fishilevich E, Rangasamy M, Khajuria C, McCaskill DG, Pereira AE, Gandra P, Frey ML, Worden SE, Whitlock SL, Lo W, Schnelle KD, Lutz JR, Narva KE, Siegfried BD. Control of western corn rootworm via RNAi traits in maize: lethal and sublethal effects of Sec23 dsRNA. Pest Manag Sci 2020; 76:1500-1512. [PMID: 31677217 DOI: 10.1002/ps.5666] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 10/10/2019] [Accepted: 10/28/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND RNA interference (RNAi) triggered by maize plants expressing RNA hairpins against specific western corn rootworm (WCR) transcripts have proven to be effective at controlling this pest. To provide robust crop protection, mRNA transcripts targeted by double-stranded RNA must be sensitive to knockdown and encode essential proteins. RESULTS Using WCR adult feeding assays, we identified Sec23 as a highly lethal RNAi target. Sec23 encodes a coatomer protein, a component of the coat protein (COPII) complex that mediates ER-Golgi transport. The lethality detected in WCR adults was also observed in early instar larvae, the life stage causing most of the crop damage, suggesting that WCR adults can serve as an alternative to larvae for dsRNA screening. Surprisingly, over 85% transcript inhibition resulted in less than 40% protein knockdown, suggesting that complete protein knockdown is not necessary for Sec23 RNAi-mediated mortality. The efficacy of Sec23 dsRNA for rootworm control was confirmed in planta; T0 maize events carrying rootworm Sec23 hairpin transgenes showed high levels of root protection in greenhouse assays. A reduction in larval survival and weight were observed in the offspring of WCR females exposed to Sec23 dsRNA LC25 in diet bioassays. CONCLUSION We describe Sec23 as RNAi target for in planta rootworm control. High mortality in exposed adult and larvae and moderate sublethal effects in the offspring of females exposed to Sec23 dsRNA LC25 , suggest the potential for field application of this RNAi trait and the need to factor in responses to sublethal exposure into insect resistance management programs. © 2019 Society of Chemical Industry.
Collapse
Affiliation(s)
- Ana M Vélez
- Department of Entomology, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - Elane Fishilevich
- Department of Entomology, University of Nebraska-Lincoln, Lincoln, NE, USA
- Corteva Agriscience, Indianapolis, IN, USA
| | | | - Chitvan Khajuria
- Department of Entomology, University of Nebraska-Lincoln, Lincoln, NE, USA
| | | | - Adriano E Pereira
- Department of Entomology, University of Nebraska-Lincoln, Lincoln, NE, USA
| | | | | | | | | | - Wendy Lo
- Corteva Agriscience, Indianapolis, IN, USA
| | | | | | | | - Blair D Siegfried
- Entomology and Nematology Department, Charles Steinmetz Hall, University of Florida, Gainesville, FL, USA
| |
Collapse
|
5
|
Hanna MG, Peotter JL, Frankel EB, Audhya A. Membrane Transport at an Organelle Interface in the Early Secretory Pathway: Take Your Coat Off and Stay a While: Evolution of the metazoan early secretory pathway. Bioessays 2018; 40:e1800004. [PMID: 29741780 PMCID: PMC6166410 DOI: 10.1002/bies.201800004] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 04/09/2018] [Indexed: 01/25/2023]
Abstract
Most metazoan organisms have evolved a mildly acidified and calcium diminished sorting hub in the early secretory pathway commonly referred to as the Endoplasmic Reticulum-Golgi intermediate compartment (ERGIC). These membranous vesicular-tubular clusters are found tightly juxtaposed to ER subdomains that are competent for the production of COPII-coated transport carriers. In contrast to many unicellular systems, metazoan COPII carriers largely transit just a few hundred nanometers to the ERGIC, prior to COPI-dependent transport on to the cis-Golgi. The mechanisms underlying formation and maintenance of ERGIC membranes are poorly defined. However, recent evidence suggests an important role for Trk-fused gene (TFG) in regulating the integrity of the ER/ERGIC interface. Moreover, in the absence of cytoskeletal elements to scaffold tracks on which COPII carriers might move, TFG appears to promote anterograde cargo transport by locally tethering COPII carriers adjacent to ERGIC membranes. This action, regulated in part by the intrinsically disordered domain of TFG, provides sufficient time for COPII coat disassembly prior to heterotypic membrane fusion and cargo delivery to the ERGIC.
Collapse
Affiliation(s)
- Michael G. Hanna
- Department of Biomolecular Chemistry, University of Wisconsin-Madison School of Medicine and Public Health 440 Henry Mall, Madison, WI 53706, USA,
| | - Jennifer L. Peotter
- Department of Biomolecular Chemistry, University of Wisconsin-Madison School of Medicine and Public Health 440 Henry Mall, Madison, WI 53706, USA,
| | - E. B. Frankel
- Department of Biomolecular Chemistry, University of Wisconsin-Madison School of Medicine and Public Health 440 Henry Mall, Madison, WI 53706, USA,
| | - Anjon Audhya
- Department of Biomolecular Chemistry, University of Wisconsin-Madison School of Medicine and Public Health 440 Henry Mall, Madison, WI 53706, USA,
| |
Collapse
|
6
|
Gan W, Zhang C, Siu KY, Satoh A, Tanner JA, Yu S. ULK1 phosphorylates Sec23A and mediates autophagy-induced inhibition of ER-to-Golgi traffic. BMC Cell Biol 2017; 18:22. [PMID: 28486929 PMCID: PMC5424413 DOI: 10.1186/s12860-017-0138-8] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 04/20/2017] [Indexed: 02/04/2023] Open
Abstract
Background Autophagy is an inducible autodigestive process that allows cells to recycle proteins and other materials for survival during stress and nutrient deprived conditions. The kinase ULK1 is required to activate this process. ULK1 phosphorylates a number of target proteins and regulates many cellular processes including the early secretory pathway. Recently, ULK1 has been demonstrated to phosphorylate Sec16 and affects the transport of serotonin transporter at the ER exit sites (ERES), but whether ULK1 may affect the transport of other cargo proteins and general secretion has not been fully addressed. Results In this study, we identified Sec23A, a component of the COPII vesicle coat, as a target of ULK1 phosphorylation. Elevated autophagy, induced by amino acid starvation, rapamycin, or overexpression of ULK1 caused aggregation of the ERES, a region of the ER dedicated for the budding of COPII vesicles. Transport of cargo proteins was also inhibited under these conditions and was retained at the ERES. ULK1 phosphorylation of Sec23A reduced the interaction between Sec23A and Sec31A. We identified serine 207, serine 312 and threonine 405 on Sec23A as ULK1 phosphorylation sites. Among these residues, serine 207, when changed to phospho-deficient and phospho-mimicking mutants, most faithfully recapitulated the above-mentioned effects of ULK1 phospho-regulation. Conclusion These findings identify Sec23A as a new target of ULK1 and uncover a mechanism of coordinating intracellular protein transport and autophagy. Electronic supplementary material The online version of this article (doi:10.1186/s12860-017-0138-8) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Wenjia Gan
- School of Biomedical Sciences, Shatin, N.T., Hong Kong, Special Administrative Region of China.,Department of Clinical Laboratory, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, People's Republic of China
| | - Caiyun Zhang
- School of Biomedical Sciences, Shatin, N.T., Hong Kong, Special Administrative Region of China
| | - Ka Yu Siu
- School of Biomedical Sciences, Shatin, N.T., Hong Kong, Special Administrative Region of China
| | - Ayano Satoh
- The Graduate School of Natural Science and Technology, Okayama University, Tsushima naka 3-1-1, Okayama, 7008530, Japan
| | - Julian A Tanner
- School of Biomedical Sciences, University of Hong Kong, 21 Sassoon Road, Pok Fu Lam, Hong Kong, Special Administrative Region of China
| | - Sidney Yu
- School of Biomedical Sciences, Shatin, N.T., Hong Kong, Special Administrative Region of China. .,Epithelial Cell Biology Research Center, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, Special Administrative Region of China.
| |
Collapse
|
7
|
Zeng Y, Chung KP, Li B, Lai CM, Lam SK, Wang X, Cui Y, Gao C, Luo M, Wong KB, Schekman R, Jiang L. Unique COPII component AtSar1a/At Sec23a pair is required for the distinct function of protein ER export in Arabidopsis thaliana. Proc Natl Acad Sci U S A 2015; 112:14360-5. [PMID: 26578783 DOI: 10.1073/pnas.1519333112] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Secretory proteins traffic from endoplasmic reticulum (ER) to Golgi via the coat protein complex II (COPII) vesicle, which consists of five cytosolic components (Sar1, Sec23-24, and Sec13-31). In eukaryotes, COPII transport has diversified due to gene duplication, creating multiple COPII paralogs. Evidence has accumulated, revealing the functional heterogeneity of COPII paralogs in protein ER export. Sar1B, the small GTPase of COPII machinery, seems to be specialized for large cargo secretion in mammals. Arabidopsis contains five Sar1 and seven Sec23 homologs, and AtSar1a was previously shown to exhibit different effects on α-amylase secretion. However, mechanisms underlying the functional diversity of Sar1 paralogs remain unclear in higher organisms. Here, we show that the Arabidopsis Sar1 homolog AtSar1a exhibits distinct localization in plant cells. Transgenic Arabidopsis plants expressing dominant-negative AtSar1a exhibit distinct effects on ER cargo export. Mutagenesis analysis identified a single amino acid, Cys84, as being responsible for the functional diversity of AtSar1a. Structure homology modeling and interaction studies revealed that Cys84 is crucial for the specific interaction of AtSar1a with AtSec23a, a distinct Arabidopsis Sec23 homolog. Structure modeling and coimmunoprecipitation further identified a corresponding amino acid, Cys484, on AtSec23a as being essential for the specific pair formation. At the cellular level, the Cys484 mutation affects the distinct function of AtSec23a on vacuolar cargo trafficking. Additionally, dominant-negative AtSar1a affects the ER export of the transcription factor bZIP28 under ER stress. We have demonstrated a unique plant pair of COPII machinery function in ER export and the mechanism underlying the functional diversity of COPII paralogs in eukaryotes.
Collapse
|
8
|
Amodio G, Venditti R, De Matteis MA, Moltedo O, Pignataro P, Remondelli P. Endoplasmic reticulum stress reduces COPII vesicle formation and modifies Sec23a cycling at ERESs. FEBS Lett 2013; 587:3261-6. [PMID: 23994533 DOI: 10.1016/j.febslet.2013.08.021] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Accepted: 08/08/2013] [Indexed: 01/03/2023]
Abstract
Exit from the Endoplasmic Reticulum (ER) of newly synthesized proteins is mediated by COPII vesicles that bud from the ER at the ER Exit Sites (ERESs). Disruption of ER homeostasis causes accumulation of unfolded and misfolded proteins in the ER. This condition is referred to as ER stress. Previously, we demonstrated that ER stress rapidly impairs the formation of COPII vesicles. Here, we show that membrane association of COPII components, and in particular of Sec23a, is impaired by ER stress-inducing agents suggesting the existence of a dynamic interplay between protein folding and COPII assembly at the ER.
Collapse
Affiliation(s)
- Giuseppina Amodio
- Dipartimento di Farmacia, Università degli Studi di Salerno, 84084 Fisciano, Salerno, Italy
| | | | | | | | | | | |
Collapse
|