51
|
Hashimoto H, Ramirez DH, Lautier O, Pawlak N, Blobel G, Palancade B, Debler EW. Structure of the pre-mRNA leakage 39-kDa protein reveals a single domain of integrated zf-C3HC and Rsm1 modules. Sci Rep 2022; 12:17691. [PMID: 36271106 PMCID: PMC9586977 DOI: 10.1038/s41598-022-22183-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 10/11/2022] [Indexed: 01/18/2023] Open
Abstract
In Saccharomyces cerevisiae, the pre-mRNA leakage 39-kDa protein (ScPml39) was reported to retain unspliced pre-mRNA prior to export through nuclear pore complexes (NPCs). Pml39 homologs outside the Saccharomycetaceae family are currently unknown, and mechanistic insight into Pml39 function is lacking. Here we determined the crystal structure of ScPml39 at 2.5 Å resolution to facilitate the discovery of orthologs beyond Saccharomycetaceae, e.g. in Schizosaccharomyces pombe or human. The crystal structure revealed integrated zf-C3HC and Rsm1 modules, which are tightly associated through a hydrophobic interface to form a single domain. Both zf-C3HC and Rsm1 modules belong to the Zn-containing BIR (Baculovirus IAP repeat)-like super family, with key residues of the canonical BIR domain being conserved. Features unique to the Pml39 modules refer to the spacing between the Zn-coordinating residues, giving rise to a substantially tilted helix αC in the zf-C3HC and Rsm1 modules, and an extra helix αAB' in the Rsm1 module. Conservation of key residues responsible for its distinct features identifies S. pombe Rsm1 and Homo sapiens NIPA/ZC3HC1 as structural orthologs of ScPml39. Based on the recent functional characterization of NIPA/ZC3HC1 as a scaffold protein that stabilizes the nuclear basket of the NPC, our data suggest an analogous function of ScPml39 in S. cerevisiae.
Collapse
Affiliation(s)
- Hideharu Hashimoto
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | - Daniel H Ramirez
- Laboratory of Cell Biology, Howard Hughes Medical Institute, The Rockefeller University, New York, NY, 10065, USA
| | - Ophélie Lautier
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013, Paris, France
| | - Natalie Pawlak
- Laboratory of Cell Biology, Howard Hughes Medical Institute, The Rockefeller University, New York, NY, 10065, USA
| | - Günter Blobel
- Laboratory of Cell Biology, Howard Hughes Medical Institute, The Rockefeller University, New York, NY, 10065, USA
| | - Benoît Palancade
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013, Paris, France.
| | - Erik W Debler
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, PA, 19107, USA.
- Laboratory of Cell Biology, Howard Hughes Medical Institute, The Rockefeller University, New York, NY, 10065, USA.
| |
Collapse
|
52
|
Pladevall-Morera D, Zylicz JJ. Chromatin as a sensor of metabolic changes during early development. Front Cell Dev Biol 2022; 10:1014498. [PMID: 36299478 PMCID: PMC9588933 DOI: 10.3389/fcell.2022.1014498] [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: 08/08/2022] [Accepted: 09/13/2022] [Indexed: 11/13/2022] Open
Abstract
Cellular metabolism is a complex network of biochemical reactions fueling development with energy and biomass; however, it can also shape the cellular epigenome. Indeed, some intermediates of metabolic reactions exert a non-canonical function by acting as co-factors, substrates or inhibitors of chromatin modifying enzymes. Therefore, fluctuating availability of such molecules has the potential to regulate the epigenetic landscape. Thanks to this functional coupling, chromatin can act as a sensor of metabolic changes and thus impact cell fate. Growing evidence suggest that both metabolic and epigenetic reprogramming are crucial for ensuring a successful embryo development from the zygote until gastrulation. In this review, we provide an overview of the complex relationship between metabolism and epigenetics in regulating the early stages of mammalian embryo development. We report on recent breakthroughs in uncovering the non-canonical functions of metabolism especially when re-localized to the nucleus. In addition, we identify the challenges and outline future perspectives to advance the novel field of epi-metabolomics especially in the context of early development.
Collapse
|
53
|
Archambault V, Li J, Emond-Fraser V, Larouche M. Dephosphorylation in nuclear reassembly after mitosis. Front Cell Dev Biol 2022; 10:1012768. [PMID: 36268509 PMCID: PMC9576876 DOI: 10.3389/fcell.2022.1012768] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Accepted: 08/31/2022] [Indexed: 11/13/2022] Open
Abstract
In most animal cell types, the interphase nucleus is largely disassembled during mitotic entry. The nuclear envelope breaks down and chromosomes are compacted into separated masses. Chromatin organization is also mostly lost and kinetochores assemble on centromeres. Mitotic protein kinases play several roles in inducing these transformations by phosphorylating multiple effector proteins. In many of these events, the mechanistic consequences of phosphorylation have been characterized. In comparison, how the nucleus reassembles at the end of mitosis is less well understood in mechanistic terms. In recent years, much progress has been made in deciphering how dephosphorylation of several effector proteins promotes nuclear envelope reassembly, chromosome decondensation, kinetochore disassembly and interphase chromatin organization. The precise roles of protein phosphatases in this process, in particular of the PP1 and PP2A groups, are emerging. Moreover, how these enzymes are temporally and spatially regulated to ensure that nuclear reassembly progresses in a coordinated manner has been partly uncovered. This review provides a global view of nuclear reassembly with a focus on the roles of dephosphorylation events. It also identifies important open questions and proposes hypotheses.
Collapse
Affiliation(s)
- Vincent Archambault
- Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, QC, Canada
- Département de Biochimie et Médecine Moléculaire, Université de Montréal, Montréal, QC, Canada
- *Correspondence: Vincent Archambault,
| | - Jingjing Li
- Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, QC, Canada
- Département de Biochimie et Médecine Moléculaire, Université de Montréal, Montréal, QC, Canada
| | - Virginie Emond-Fraser
- Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, QC, Canada
- Département de Biochimie et Médecine Moléculaire, Université de Montréal, Montréal, QC, Canada
| | - Myreille Larouche
- Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, QC, Canada
| |
Collapse
|
54
|
Sending the message: specialized RNA export mechanisms in trypanosomes. Trends Parasitol 2022; 38:854-867. [PMID: 36028415 PMCID: PMC9894534 DOI: 10.1016/j.pt.2022.07.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 07/25/2022] [Accepted: 07/25/2022] [Indexed: 02/04/2023]
Abstract
Export of RNA from the nucleus is essential for all eukaryotic cells and has emerged as a major step in the control of gene expression. mRNA molecules are required to complete a complex series of processing events and pass a quality control system to protect the cytoplasm from the translation of aberrant proteins. Many of these events are highly conserved across eukaryotes, reflecting their ancient origin, but significant deviation from a canonical pathway as described from animals and fungi has emerged in the trypanosomatids. With significant implications for the mechanisms that control gene expression and hence differentiation, responses to altered environments and fitness as a parasite, these deviations may also reveal additional, previously unsuspected, mRNA export pathways.
Collapse
|
55
|
Borah S, Dhanasekaran K, Kumar S. The LEM-ESCRT toolkit: Repair and maintenance of the nucleus. Front Cell Dev Biol 2022; 10:989217. [PMID: 36172278 PMCID: PMC9512039 DOI: 10.3389/fcell.2022.989217] [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: 07/08/2022] [Accepted: 08/24/2022] [Indexed: 12/04/2022] Open
Abstract
The eukaryotic genome is enclosed in a nuclear envelope that protects it from potentially damaging cellular activities and physically segregates transcription and translation.Transport across the NE is highly regulated and occurs primarily via the macromolecular nuclear pore complexes.Loss of nuclear compartmentalization due to defects in NPC function and NE integrity are tied to neurological and ageing disorders like Alzheimer’s, viral pathogenesis, immune disorders, and cancer progression.Recent work implicates inner-nuclear membrane proteins of the conserved LEM domain family and the ESCRT machinery in NE reformation during cell division and NE repair upon rupture in migrating cancer cells, and generating seals over defective NPCs. In this review, we discuss the recent in-roads made into defining the molecular mechanisms and biochemical networks engaged by LEM and many other integral inner nuclear membrane proteins to preserve the nuclear barrier.
Collapse
Affiliation(s)
- Sapan Borah
- National Institute of Immunohaematology, Mumbai, Maharashtra, India
- *Correspondence: Sapan Borah, ; Karthigeyan Dhanasekaran, ; Santosh Kumar,
| | - Karthigeyan Dhanasekaran
- Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, Haryana, India
- *Correspondence: Sapan Borah, ; Karthigeyan Dhanasekaran, ; Santosh Kumar,
| | - Santosh Kumar
- National Centre for Cell Science, Pune, Maharashtra, India
- *Correspondence: Sapan Borah, ; Karthigeyan Dhanasekaran, ; Santosh Kumar,
| |
Collapse
|
56
|
Mannino PJ, Lusk CP. Quality control mechanisms that protect nuclear envelope identity and function. J Biophys Biochem Cytol 2022; 221:213424. [PMID: 36036741 PMCID: PMC9442147 DOI: 10.1083/jcb.202205123] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 08/08/2022] [Accepted: 08/10/2022] [Indexed: 11/22/2022] Open
Abstract
The nuclear envelope (NE) is a specialization of the endoplasmic reticulum with distinct biochemistry that defines inner and outer membranes connected at a pore membrane that houses nuclear pore complexes (NPCs). Quality control mechanisms that maintain the physical integrity and biochemical identity of these membranes are critical to ensure that the NE acts as a selective barrier that also contributes to genome stability and metabolism. As the proteome of the NE is highly integrated, it is challenging to turn over by conventional ubiquitin-proteasome and autophagy mechanisms. Further, removal of entire sections of the NE requires elaborate membrane remodeling that is poorly understood. Nonetheless, recent work has made inroads into discovering specializations of cellular degradative machineries tailored to meeting the unique challenges imposed by the NE. In addition, cells have evolved mechanisms to surveil and repair the NE barrier to protect against the deleterious effects of a breach in NE integrity, in the form of either a ruptured NE or a dysfunctional NPC. Here, we synthesize the most recent work exploring NE quality control mechanisms across eukaryotes.
Collapse
|
57
|
Kralt A, Wojtynek M, Fischer JS, Agote-Aran A, Mancini R, Dultz E, Noor E, Uliana F, Tatarek-Nossol M, Antonin W, Onischenko E, Medalia O, Weis K. An amphipathic helix in Brl1 is required for nuclear pore complex biogenesis in S. cerevisiae. eLife 2022; 11:78385. [PMID: 36000978 PMCID: PMC9402233 DOI: 10.7554/elife.78385] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 08/03/2022] [Indexed: 12/28/2022] Open
Abstract
The nuclear pore complex (NPC) is the central portal for macromolecular exchange between the nucleus and cytoplasm. In all eukaryotes, NPCs assemble into an intact nuclear envelope (NE) during interphase, but the process of NPC biogenesis remains poorly characterized. Furthermore, little is known about how NPC assembly leads to the fusion of the outer and inner NE, and no factors have been identified that could trigger this event. Here, we characterize the transmembrane protein Brl1 as an NPC assembly factor required for NE fusion in budding yeast. Brl1 preferentially associates with NPC assembly intermediates and its depletion halts NPC biogenesis, leading to NE herniations that contain inner and outer ring nucleoporins but lack the cytoplasmic export platform. Furthermore, we identify an essential amphipathic helix in the luminal domain of Brl1 that mediates interactions with lipid bilayers. Mutations in this amphipathic helix lead to NPC assembly defects, and cryo-electron tomography analyses reveal multilayered herniations of the inner nuclear membrane with NPC-like structures at the neck, indicating a failure in NE fusion. Taken together, our results identify a role for Brl1 in NPC assembly and suggest a function of its amphipathic helix in mediating the fusion of the inner and outer nuclear membranes.
Collapse
Affiliation(s)
- Annemarie Kralt
- Institute of Biochemistry, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Matthias Wojtynek
- Institute of Biochemistry, Department of Biology, ETH Zurich, Zurich, Switzerland.,Department of Biochemistry, University of Zurich, Zürich, Switzerland
| | - Jonas S Fischer
- Institute of Biochemistry, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Arantxa Agote-Aran
- Institute of Biochemistry, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Roberta Mancini
- Institute of Biochemistry, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Elisa Dultz
- Institute of Biochemistry, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Elad Noor
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Federico Uliana
- Institute of Biochemistry, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Marianna Tatarek-Nossol
- Institute of Biochemistry and Molecular Cell Biology, Medical School, RWTH Aachen University, Aachen, Germany
| | - Wolfram Antonin
- Institute of Biochemistry and Molecular Cell Biology, Medical School, RWTH Aachen University, Aachen, Germany
| | - Evgeny Onischenko
- Department of Biological Sciences, University of Bergen, Bergen, Norway
| | - Ohad Medalia
- Department of Biochemistry, University of Zurich, Zürich, Switzerland
| | - Karsten Weis
- Institute of Biochemistry, Department of Biology, ETH Zurich, Zurich, Switzerland
| |
Collapse
|
58
|
Inagaki E, Yoshimatsu S, Okano H. Accelerated neuronal aging in vitro ∼melting watch ∼. Front Aging Neurosci 2022; 14:868770. [PMID: 36016855 PMCID: PMC9397486 DOI: 10.3389/fnagi.2022.868770] [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: 02/03/2022] [Accepted: 07/04/2022] [Indexed: 11/13/2022] Open
Abstract
In developed countries, the aging of the population and the associated increase in age-related diseases are causing major unresolved medical, social, and environmental matters. Therefore, research on aging has become one of the most important and urgent issues in life sciences. If the molecular mechanisms of the onset and progression of neurodegenerative diseases are elucidated, we can expect to develop disease-modifying methods to prevent neurodegeneration itself. Since the discovery of induced pluripotent stem cells (iPSCs), there has been an explosion of disease models using disease-specific iPSCs derived from patient-derived somatic cells. By inducing the differentiation of iPSCs into neurons, disease models that reflect the patient-derived pathology can be reproduced in culture dishes, and are playing an active role in elucidating new pathological mechanisms and as a platform for new drug discovery. At the same time, however, we are faced with a new problem: how to recapitulate aging in culture dishes. It has been pointed out that cells differentiated from pluripotent stem cells are juvenile, retain embryonic traits, and may not be fully mature. Therefore, attempts are being made to induce cell maturation, senescence, and stress signals through culture conditions. It has also been reported that direct conversion of fibroblasts into neurons can reproduce human neurons with an aged phenotype. Here, we outline some state-of-the-art insights into models of neuronal aging in vitro. New frontiers in which stem cells and methods for inducing differentiation of tissue regeneration can be applied to aging research are just now approaching, and we need to keep a close eye on them. These models are forefront and intended to advance our knowledge of the molecular mechanisms of aging and contribute to the development of novel therapies for human neurodegenerative diseases associated with aging.
Collapse
Affiliation(s)
- Emi Inagaki
- Department of Physiology, Keio University School of Medicine, Tokyo, Japan
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
- Japanese Society for the Promotion of Science (JSPS), Tokyo, Japan
| | - Sho Yoshimatsu
- Department of Physiology, Keio University School of Medicine, Tokyo, Japan
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
| | - Hideyuki Okano
- Department of Physiology, Keio University School of Medicine, Tokyo, Japan
- *Correspondence: Hideyuki Okano,
| |
Collapse
|
59
|
Nag N, Tripathi T. Tau-FG-nucleoporin98 interaction and impaired nucleocytoplasmic transport in Alzheimer's disease. Brief Funct Genomics 2022; 22:161-167. [PMID: 35923096 DOI: 10.1093/bfgp/elac022] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 06/29/2022] [Accepted: 07/11/2022] [Indexed: 11/14/2022] Open
Abstract
An emerging pathophysiology associated with the neurodegenerative Alzheimer's disease (AD) is the impairment of nucleocytoplasmic transport (NCT). The impairment can originate from damage to the nuclear pore complex (NPC) or other factors involved in NCT. The phenylalanine-glycine nucleoporins (FG-Nups) form a crucial component of the NPC, which is central to NCT. Recent discoveries have highlighted that the neuropathological protein tau is involved in direct interactions with the FG-Nups and impairment of the NCT process. Targeting such interactions may lead to the identification of novel interaction inhibitors and offer new therapeutic alternatives for the treatment of AD. This review highlights recent findings associated with impaired NCT in AD and the interaction between tau and the FG-Nups.
Collapse
Affiliation(s)
- Niharika Nag
- Molecular and Structural Biophysics Laboratory, Department of Biochemistry, North-Eastern Hill University, Shillong 793022, India
| | - Timir Tripathi
- Regional Director's Office, Indira Gandhi National Open University (IGNOU), Regional Centre Kohima, Kenuozou, Kohima 797001, India
| |
Collapse
|
60
|
Up-regulation of POM121 is linked to prostate cancer aggressiveness and serves as a prognostic biomarker. Urol Oncol 2022; 40:380.e11-380.e18. [DOI: 10.1016/j.urolonc.2022.05.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 03/13/2022] [Accepted: 05/19/2022] [Indexed: 11/18/2022]
|
61
|
Lim S, Liu Y, Rhie BH, Kim C, Ryu HY, Ahn SH. Sus1 maintains a normal lifespan through regulation of TREX-2 complex-mediated mRNA export. Aging (Albany NY) 2022; 14:4990-5012. [PMID: 35771153 PMCID: PMC9271307 DOI: 10.18632/aging.204146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 06/14/2022] [Indexed: 11/29/2022]
Abstract
Eukaryotic gene expression requires multiple cellular events, including transcription and RNA processing and transport. Sus1, a common subunit in both the Spt-Ada-Gcn5 acetyltransferase (SAGA) and transcription and export complex-2 (TREX-2) complexes, is a key factor in coupling transcription activation to mRNA nuclear export. Here, we report that the SAGA DUB module and TREX-2 distinctly regulate yeast replicative lifespan in a Sir2-dependent and -independent manner, respectively. The growth and lifespan impaired by SUS1 loss depend on TREX-2 but not on the SAGA DUB module. Notably, an increased dose of the mRNA export factors Mex67 and Dbp5 rescues the growth defect, shortened lifespan, and nuclear accumulation of poly(A)+ RNA in sus1Δ cells, suggesting that boosting the mRNA export process restores the mRNA transport defect and the growth and lifespan damage in sus1Δ cells. Moreover, Sus1 is required for the proper association of Mex67 and Dbp5 with the nuclear rim. Together, these data indicate that Sus1 links transcription and mRNA nuclear export to the lifespan control pathway, suggesting that prevention of an abnormal accumulation of nuclear RNA is necessary for maintenance of a normal lifespan.
Collapse
Affiliation(s)
- Suji Lim
- Department of Molecular and Life Science, College of Science and Convergence Technology, Hanyang University, Ansan, Gyeonggi-do 15588, Republic of Korea
| | - Yan Liu
- Department of Molecular and Life Science, College of Science and Convergence Technology, Hanyang University, Ansan, Gyeonggi-do 15588, Republic of Korea
| | - Byung-Ho Rhie
- Department of Molecular and Life Science, College of Science and Convergence Technology, Hanyang University, Ansan, Gyeonggi-do 15588, Republic of Korea
| | - Chun Kim
- Department of Molecular and Life Science, College of Science and Convergence Technology, Hanyang University, Ansan, Gyeonggi-do 15588, Republic of Korea
| | - Hong-Yeoul Ryu
- BK21 Plus KNU Creative BioResearch Group, School of Life Sciences, College of National Sciences, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Seong Hoon Ahn
- Department of Molecular and Life Science, College of Science and Convergence Technology, Hanyang University, Ansan, Gyeonggi-do 15588, Republic of Korea
| |
Collapse
|
62
|
Tingey M, Yang W. Unraveling docking and initiation of mRNA export through the nuclear pore complex. Bioessays 2022; 44:e2200027. [PMID: 35754154 PMCID: PMC9308666 DOI: 10.1002/bies.202200027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 05/18/2022] [Accepted: 06/03/2022] [Indexed: 11/07/2022]
Abstract
The nuclear export of mRNA through the nuclear pore complex (NPC) is a process required for the healthy functioning of human cells, making it a critical area of research. However, the geometries of mRNA and the NPC are well below the diffraction limit of light microscopy, thereby presenting significant challenges in evaluating the discrete interactions and dynamics involved in mRNA nuclear export through the native NPC. Recent advances in biotechnology and single-molecule super-resolution light microscopy have enabled researchers to gain granular insight into the specific contributions made by discrete nucleoporins in the nuclear basket of the NPC to the export of mRNA. Specifically, by expanding upon the docking step facilitated by the protein TPR in the nuclear basket as well as identifying NUP153 as being the primary nuclear basket protein initiating export through the central channel of the NPC.
Collapse
Affiliation(s)
- Mark Tingey
- Department of Biology, Temple University, Philadelphia, Pennsylvania, USA
| | - Weidong Yang
- Department of Biology, Temple University, Philadelphia, Pennsylvania, USA
| |
Collapse
|
63
|
Size regulation of multiple organelles competing for a limiting subunit pool. PLoS Comput Biol 2022; 18:e1010253. [PMID: 35714135 PMCID: PMC9246132 DOI: 10.1371/journal.pcbi.1010253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 06/30/2022] [Accepted: 05/26/2022] [Indexed: 11/20/2022] Open
Abstract
How cells regulate the size of intracellular structures and organelles is a longstanding question. Recent experiments suggest that size control of intracellular structures is achieved through the depletion of a limiting subunit pool in the cytoplasm. While the limiting pool model ensures organelle-to-cell size scaling, it does not provide a mechanism for robust size control of multiple co-existing structures. Here we develop a generalized theory for size-dependent growth of intracellular structures to demonstrate that robust size control of multiple intracellular structures, competing for a limiting subunit pool, is achieved via a negative feedback between the growth rate and the size of the individual structure. This design principle captures size maintenance of a wide variety of subcellular structures, from cytoskeletal filaments to three-dimensional organelles. We identify the feedback motifs for structure size regulation based on known molecular processes, and compare our theory to existing models of size regulation in biological assemblies. Furthermore, we show that positive feedback between structure size and growth rate can lead to bistable size distribution and spontaneous size selection. Organelle size control is essential for the proper physiological functioning of eukaryotic cells, but the underlying mechanisms of size regulation remain poorly understood. By developing a general theory for organelle size control, we show that robust size control of intracellular structures and organelles is achieved via a negative feedback between individual organelle size and their net growth rates. This design principle not only describes size maintenance of single organelles, but also ensures size stability of multiple co-existing organelles that are built from a limiting pool of subunits. Our results delineate the role of limiting pool as a size scaling mechanism rather than a size control mechanism, supporting the idea that negative feedback control of organelle size via depletion of a limiting subunit pool is not sufficient to maintain the size of multiple competing organelles. In the case of positive feedback between organelle size and growth rate, our model reproduces phenomena such as bistability in organelle size distribution and spontaneous emergence of cell polarity.
Collapse
|
64
|
Gleixner AM, Verdone BM, Otte CG, Anderson EN, Ramesh N, Shapiro OR, Gale JR, Mauna JC, Mann JR, Copley KE, Daley EL, Ortega JA, Cicardi ME, Kiskinis E, Kofler J, Pandey UB, Trotti D, Donnelly CJ. NUP62 localizes to ALS/FTLD pathological assemblies and contributes to TDP-43 insolubility. Nat Commun 2022; 13:3380. [PMID: 35697676 PMCID: PMC9192689 DOI: 10.1038/s41467-022-31098-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Accepted: 06/03/2022] [Indexed: 01/12/2023] Open
Abstract
A G4C2 hexanucleotide repeat expansion in the C9orf72 gene is the most common genetic cause of ALS and FTLD (C9-ALS/FTLD) with cytoplasmic TDP-43 inclusions observed in regions of neurodegeneration. The accumulation of repetitive RNAs and dipeptide repeat protein (DPR) are two proposed mechanisms of toxicity in C9-ALS/FTLD and linked to impaired nucleocytoplasmic transport. Nucleocytoplasmic transport is regulated by the phenylalanine-glycine nucleoporins (FG nups) that comprise the nuclear pore complex (NPC) permeability barrier. However, the relationship between FG nups and TDP-43 pathology remains elusive. Our studies show that nuclear depletion and cytoplasmic mislocalization of one FG nup, NUP62, is linked to TDP-43 mislocalization in C9-ALS/FTLD iPSC neurons. Poly-glycine arginine (GR) DPR accumulation initiates the formation of cytoplasmic RNA granules that recruit NUP62 and TDP-43. Cytoplasmic NUP62 and TDP-43 interactions promotes their insolubility and NUP62:TDP-43 inclusions are frequently found in C9orf72 ALS/FTLD as well as sporadic ALS/FTLD postmortem CNS tissue. Our findings indicate NUP62 cytoplasmic mislocalization contributes to TDP-43 proteinopathy in ALS/FTLD.
Collapse
Affiliation(s)
- Amanda M Gleixner
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- LiveLikeLou Center for ALS Research, University of Pittsburgh Brain Institute, Pittsburgh, PA, USA
| | - Brandie Morris Verdone
- Department of Neuroscience, Jefferson Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Thomas Jefferson University, Philadelphia, PA, USA
| | - Charlton G Otte
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- LiveLikeLou Center for ALS Research, University of Pittsburgh Brain Institute, Pittsburgh, PA, USA
- Physician Scientist Training Program, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Eric N Anderson
- Department of Pediatrics, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Nandini Ramesh
- Department of Pediatrics, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
- Department of Human Genetics, University of Pittsburgh Graduate School of Public Health, Pittsburgh, PA, USA
| | - Olivia R Shapiro
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- LiveLikeLou Center for ALS Research, University of Pittsburgh Brain Institute, Pittsburgh, PA, USA
| | - Jenna R Gale
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- LiveLikeLou Center for ALS Research, University of Pittsburgh Brain Institute, Pittsburgh, PA, USA
| | - Jocelyn C Mauna
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- LiveLikeLou Center for ALS Research, University of Pittsburgh Brain Institute, Pittsburgh, PA, USA
| | - Jacob R Mann
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- LiveLikeLou Center for ALS Research, University of Pittsburgh Brain Institute, Pittsburgh, PA, USA
- Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, USA
| | - Katie E Copley
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- LiveLikeLou Center for ALS Research, University of Pittsburgh Brain Institute, Pittsburgh, PA, USA
| | - Elizabeth L Daley
- The Ken & Ruth Davee Department of Neurology, Northwestern University of Feinberg School of Medicine, Chicago, IL, USA
| | - Juan A Ortega
- The Ken & Ruth Davee Department of Neurology, Northwestern University of Feinberg School of Medicine, Chicago, IL, USA
| | - Maria Elena Cicardi
- Department of Neuroscience, Jefferson Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Thomas Jefferson University, Philadelphia, PA, USA
| | - Evangelos Kiskinis
- The Ken & Ruth Davee Department of Neurology, Northwestern University of Feinberg School of Medicine, Chicago, IL, USA
- Department of Neuroscience, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Julia Kofler
- LiveLikeLou Center for ALS Research, University of Pittsburgh Brain Institute, Pittsburgh, PA, USA
- Department of Pathology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Udai B Pandey
- LiveLikeLou Center for ALS Research, University of Pittsburgh Brain Institute, Pittsburgh, PA, USA
- Department of Human Genetics, University of Pittsburgh Graduate School of Public Health, Pittsburgh, PA, USA
- Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, USA
| | - Davide Trotti
- Department of Neuroscience, Jefferson Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Thomas Jefferson University, Philadelphia, PA, USA
| | - Christopher J Donnelly
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
- LiveLikeLou Center for ALS Research, University of Pittsburgh Brain Institute, Pittsburgh, PA, USA.
- Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, USA.
| |
Collapse
|
65
|
A role for nuclear stretching and NPCs changes in the cytoplasmic-nuclear trafficking of YAP: An experimental and numerical modelling approach. Mater Today Bio 2022; 15:100335. [PMID: 35813578 PMCID: PMC9263995 DOI: 10.1016/j.mtbio.2022.100335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 05/27/2022] [Accepted: 06/16/2022] [Indexed: 11/22/2022] Open
Abstract
Mechanical forces, acting on eukaryotic cells, are responsible for cell shape, cell proliferation, cell polarity, and cell differentiation thanks to two cells abilities known as mechanosensing and mechanotransduction. Mechanosensing consists of the ability of a cell to sense mechanical cues, while mechanotransduction is the capacity of a cell to respond to these signals by translating mechanical stimuli into biochemical ones. These signals propagate from the extracellular matrix to the nucleus with different well known physical connections, but how the mechanical signals are transduced into biochemical ones remains an open challenge. Recent findings showed that the cell-generated forces affect the translocation of transcription factors (TFs) from the cytoplasm to the nucleus. This mechanism is affected by the features of nuclear pore complexes. Owing to the complex patterns of strains and stresses of the nuclear envelope caused by cytoskeletal forces, it is likely that the morphology of NPC changes as cytoskeleton assemblies’ change. This may ultimately affect molecular transport through the nucleus, hence altering cell functions. Among the various TFs, Yes-associated protein (YAP), which is typically involved in cell proliferation, survival, and differentiation, is able to activate specific pathways when entrapped into the cell nucleus. Here, starting from experimental results, we develop a multiscale finite element (FE) model aimed to simulate the macroscopic cell spreading and consequent changes in the cell mechanical behaviour to be related to the NPCs changes and YAP nuclear transport.
Collapse
|
66
|
Andreu I, Granero-Moya I, Chahare NR, Clein K, Molina-Jordán M, Beedle AEM, Elosegui-Artola A, Abenza JF, Rossetti L, Trepat X, Raveh B, Roca-Cusachs P. Mechanical force application to the nucleus regulates nucleocytoplasmic transport. Nat Cell Biol 2022; 24:896-905. [PMID: 35681009 PMCID: PMC7614780 DOI: 10.1038/s41556-022-00927-7] [Citation(s) in RCA: 54] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 04/26/2022] [Indexed: 12/30/2022]
Abstract
Mechanical force controls fundamental cellular processes in health and disease, and increasing evidence shows that the nucleus both experiences and senses applied forces. Such forces can lead to the nuclear translocation of proteins, but whether force controls nucleocytoplasmic transport, and how, remains unknown. Here we show that nuclear forces differentially control passive and facilitated nucleocytoplasmic transport, setting the rules for the mechanosensitivity of shuttling proteins. We demonstrate that nuclear force increases permeability across nuclear pore complexes, with a dependence on molecular weight that is stronger for passive than for facilitated diffusion. Owing to this differential effect, force leads to the translocation of cargoes into or out of the nucleus within a given range of molecular weight and affinity for nuclear transport receptors. Further, we show that the mechanosensitivity of several transcriptional regulators can be both explained by this mechanism and engineered exogenously by introducing appropriate nuclear localization signals. Our work unveils a mechanism of mechanically induced signalling, probably operating in parallel with others, with potential applicability across signalling pathways.
Collapse
Affiliation(s)
- Ion Andreu
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain.
- Universidad de Navarra, TECNUN Escuela de Ingeniería, Donostia-San Sebastián, Spain.
| | - Ignasi Granero-Moya
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain
- Universitat de Barcelona, Barcelona, Spain
| | - Nimesh R Chahare
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain
| | - Kessem Clein
- School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Marc Molina-Jordán
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain
- Universitat de Barcelona, Barcelona, Spain
| | - Amy E M Beedle
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain
- Department of Physics, King's College London, London, UK
| | - Alberto Elosegui-Artola
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain
- Department of Physics, King's College London, London, UK
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
- Cell and Tissue Mechanobiology Laboratory, The Francis Crick Institute, London, UK
| | - Juan F Abenza
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain
| | - Leone Rossetti
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain
| | - Xavier Trepat
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain
- Universitat de Barcelona, Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
- Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Barcelona, Spain
| | - Barak Raveh
- School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Pere Roca-Cusachs
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain.
- Universitat de Barcelona, Barcelona, Spain.
| |
Collapse
|
67
|
Andreu I, Granero-Moya I, Garcia-Manyes S, Roca-Cusachs P. Understanding the role of mechanics in nucleocytoplasmic transport. APL Bioeng 2022; 6:020901. [PMID: 35783457 PMCID: PMC9246425 DOI: 10.1063/5.0076034] [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: 10/20/2021] [Accepted: 02/03/2022] [Indexed: 01/26/2023] Open
Abstract
Cell nuclei are submitted to mechanical forces, which in turn affect nuclear and cell functions. Recent evidence shows that a crucial mechanically regulated nuclear function is nucleocytoplasmic transport, mediated by nuclear pore complexes (NPCs). Mechanical regulation occurs at two levels: first, by force application to the nucleus, which increases NPC permeability likely through NPC stretch. Second, by the mechanical properties of the transported proteins themselves, as mechanically labile proteins translocate through NPCs faster than mechanically stiff ones. In this perspective, we discuss this evidence and the associated mechanisms by which mechanics can regulate the nucleo-cytoplasmic partitioning of proteins. Finally, we analyze how mechanical regulation of nucleocytoplasmic transport can provide a systematic approach to the study of mechanobiology and open new avenues both in fundamental and applied research.
Collapse
Affiliation(s)
- Ion Andreu
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Technology (BIST), 08028 Barcelona, Spain
| | | | - Sergi Garcia-Manyes
- Department of Physics, Randall Centre for Cell and Molecular Biophysics, King's College London, WC2R 2LS London, United Kingdom; Single Molecule Mechanobiology Laboratory, The Francis Crick Institute, NW1 1AT London, United Kingdom
| | | |
Collapse
|
68
|
Recent Advances in Aptamer‐Based Nanopore Sensing at Single‐Molecule Resolution. Chem Asian J 2022; 17:e202200364. [DOI: 10.1002/asia.202200364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 05/20/2022] [Indexed: 11/07/2022]
|
69
|
Kose S, Imai K, Watanabe A, Nakai A, Suzuki Y, Imamoto N. Lack of Hikeshi activates HSF1 activity under normal conditions and disturbs the heat-shock response. Life Sci Alliance 2022; 5:5/9/e202101241. [PMID: 35580988 PMCID: PMC9113944 DOI: 10.26508/lsa.202101241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 04/27/2022] [Accepted: 04/27/2022] [Indexed: 01/09/2023] Open
Abstract
Hikeshi mediates the nuclear import of the molecular chaperone HSP70 under heat-shock (acute heat stress) conditions, which is crucial for recovery from cellular damage. The cytoplasmic function of HSP70 is well studied, but its nuclear roles, particularly under nonstressed conditions, remain obscure. Here, we show that Hikeshi regulates the nucleocytoplasmic distribution of HSP70 not only under heat-shock conditions but also under nonstressed conditions. Nuclear HSP70 affects the transcriptional activity of HSF1 and nuclear proteostasis under nonstressed conditions. Depletion of Hikeshi induces a reduction in nuclear HSP70 and up-regulation of the mRNA expression of genes regulated by HSF1 under nonstressed conditions. In addition, the heat-shock response is impaired in Hikeshi-knockout cells. Our results suggest that HSF1 transcriptional activity is tightly regulated by nuclear HSP70 because nuclear-localized Hsp70 effectively suppresses transcriptional activity in a dose-dependent manner. Furthermore, the cytotoxicity of nuclear pathologic polyglutamine proteins was increased by Hikeshi depletion. Thus, proper nucleocytoplasmic distribution of HSP70, mediated by Hikeshi, is required for nuclear proteostasis and adaptive response to heat shock.
Collapse
Affiliation(s)
- Shingo Kose
- Cellular Dynamics Laboratory, RIKEN Cluster for Pioneering Research, Wako, Japan,Correspondence: ;
| | - Kenichiro Imai
- Cellular and Molecular Biotechnology Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tokyo, Japan
| | - Ai Watanabe
- Cellular Dynamics Laboratory, RIKEN Cluster for Pioneering Research, Wako, Japan
| | - Akira Nakai
- Department of Biochemistry and Molecular Biology, Yamaguchi University School of Medicine, Ube, Japan
| | - Yutaka Suzuki
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Japan
| | - Naoko Imamoto
- Cellular Dynamics Laboratory, RIKEN Cluster for Pioneering Research, Wako, Japan,Correspondence: ;
| |
Collapse
|
70
|
Nuclear mRNA Export and Aging. Int J Mol Sci 2022; 23:ijms23105451. [PMID: 35628261 PMCID: PMC9142925 DOI: 10.3390/ijms23105451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 05/10/2022] [Accepted: 05/12/2022] [Indexed: 02/04/2023] Open
Abstract
The relationship between transcription and aging is one that has been studied intensively and experimentally with diverse attempts. However, the impact of the nuclear mRNA export on the aging process following its transcription is still poorly understood, although the nuclear events after transcription are coupled closely with the transcription pathway because the essential factors required for mRNA transport, namely TREX, TREX-2, and nuclear pore complex (NPC), physically and functionally interact with various transcription factors, including the activator/repressor and pre-mRNA processing factors. Dysregulation of the mediating factors for mRNA export from the nucleus generally leads to the aberrant accumulation of nuclear mRNA and further impairment in the vegetative growth and normal lifespan and the pathogenesis of neurodegenerative diseases. The optimal stoichiometry and density of NPC are destroyed during the process of cellular aging, and their damage triggers a defect of function in the nuclear permeability barrier. This review describes recent findings regarding the role of the nuclear mRNA export in cellular aging and age-related neurodegenerative disorders.
Collapse
|
71
|
Hegedűsová E, Maršalová V, Kulkarni S, Paris Z. Trafficking and/or division: Distinct roles of nucleoporins based on their location within the nuclear pore complex. RNA Biol 2022; 19:650-661. [PMID: 35491934 PMCID: PMC9067531 DOI: 10.1080/15476286.2022.2067711] [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] [Indexed: 11/23/2022] Open
Abstract
The nuclear pore complex (NPC) facilitates the trafficking of proteins and RNA between the nucleus and cytoplasm. The role of nucleoporins (Nups) in transport in the context of the NPC is well established, yet their function in tRNA export has not been fully explored. We selected several nucleoporins from different parts of the NPC to investigate their potential role in tRNA trafficking in Trypanosoma brucei. We show that while all of the nucleoporins studied are essential for cell viability, only TbNup62 and TbNup53a function in tRNA export. In contrast to homologs in yeast TbNup144 and TbNup158, which are part of the inner and outer ring of the NPC, have no role in nuclear tRNA trafficking. Instead, TbNup144 plays a critical role in nuclear division, highlighting the role of nucleoporins beyond nucleocytoplasmic transport. These results suggest that the location of nucleoporins within the NPC is crucial to maintaining various cellular processes.
Collapse
Affiliation(s)
- Eva Hegedűsová
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Veronika Maršalová
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Sneha Kulkarni
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Zdeněk Paris
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| |
Collapse
|
72
|
Yao W, Luo J, Tian H, Niu H, An X, Wang X, Zang S. Malonyl/Acetyltransferase (MAT) Knockout Decreases Triacylglycerol and Medium-Chain Fatty Acid Contents in Goat Mammary Epithelial Cells. Foods 2022; 11:foods11091291. [PMID: 35564013 PMCID: PMC9104349 DOI: 10.3390/foods11091291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 04/26/2022] [Accepted: 04/26/2022] [Indexed: 11/26/2022] Open
Abstract
Malonyl/acetyltransferase (MAT) is a crucial functional domain of fatty acid synthase (FASN), which plays a vital role in the de novo synthesis of fatty acids in vivo. Milk fatty acids are secreted by mammary epithelial cells. Mammary epithelial cells are the units of mammary gland development and function, and it is a common model for the study of mammary gland tissue development and lactation. This study aimed to investigate the effects of MAT deletion on the synthesis of triacylglycerol and medium-chain fatty acids. The MAT domain was knocked out by CRISPR/Cas9 in the goat mammary epithelial cells (GMECs), and in MAT knockout GMECs, the mRNA level of FASN was decreased by approximately 91.19% and the protein level decreased by 51.83%. The results showed that MAT deletion downregulated the contents of triacylglycerol and medium-chain fatty acids (p < 0.05) and increased the content of acetyl-Coenzyme A (acetyl-CoA) (p < 0.001). Explicit deletion of MAT resulted in significant drop of FASN, which resulted in downregulation of LPL, GPAM, DGAT2, PLIN2, XDH, ATGL, LXRα, and PPARγ genes in GMECs (p < 0.05). Meanwhile, mRNA expression levels of ACC, FASN, DGAT2, SREBP1, and LXRα decreased following treatment with acetyl-CoA (p < 0.05). Our data reveals that FASN plays critical roles in the synthesis of medium-chain fatty acids and triacylglycerol in GMECs.
Collapse
|
73
|
Using Single Molecule RNA FISH to Determine Nuclear Export and Transcription Phenotypes in Drosophila Tissues. Methods Mol Biol 2022; 2502:113-125. [PMID: 35412235 DOI: 10.1007/978-1-0716-2337-4_8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Single molecule RNA fluorescence in situ hybridization (smRNA FISH) is a widely used method for examining cellular localization of RNA and assessing gene expression outputs. The Nuclear Pore Complex (NPC) is a nuclear macro-complex known to both mediate nucleocytoplasmic transport and influence transcription via interactions with chromatin. Consequently, depletion of NPC proteins can result in defects in either transcription or nuclear export of mRNA. To distinguish between these two different functions of NPC components, it is preferable to analyze transcription and mRNA export simultaneously or in the same cell. Here, we present a smRNA FISH protocol with downstream custom MATLAB image analysis for application in Drosophila larval salivary gland tissues. This method can detect both nuclear export and transcriptional phenotypes in the same cell and as a single assay, and can be adapted to many other cell types and organisms.
Collapse
|
74
|
Ubaida-Mohien C, Spendiff S, Lyashkov A, Moaddel R, MacMillan NJ, Filion ME, Morais JA, Taivassalo T, Ferrucci L, Hepple RT. Unbiased proteomics, histochemistry, and mitochondrial DNA copy number reveal better mitochondrial health in muscle of high functioning octogenarians. eLife 2022; 11:74335. [PMID: 35404238 PMCID: PMC9090325 DOI: 10.7554/elife.74335] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 04/08/2022] [Indexed: 11/13/2022] Open
Abstract
Background: Master athletes prove that preserving a high level of physical function up to very late in life is possible, but the mechanisms responsible for their high function remain unclear. Methods: We performed muscle biopsies in 15 octogenarian world class track and field masters athletes (MA) and 14 non-athlete age/sex-matched controls (NA) to provide insights into mechanisms for preserving function in advanced age. Muscle samples were assessed for respiratory compromised fibers, mtDNA copy number, and proteomics by liquid-chromatography mass spectrometry. Results: MA exhibited markedly better performance on clinical function tests and greater cross-sectional area of the vastus lateralis muscle. Proteomics analysis revealed marked differences, where most of the ~800 differentially represented proteins in MA versus NA pertained to mitochondria structure/function such as electron transport capacity (ETC), cristae formation, mitochondrial biogenesis, and mtDNA-encoded proteins. In contrast, proteins from the spliceosome complex and nuclear pore were downregulated in MA. Consistent with proteomics data, MA had fewer respiratory compromised fibers, higher mtDNA copy number, and an increased protein ratio of the cristae-bound ETC subunits relative to the outer mitochondrial membrane protein voltage dependent anion channel. There was a substantial overlap of proteins overrepresented in MA versus NA with proteins that decline with aging and which are higher in physically active than sedentary individuals. However, we also found 176 proteins related to mitochondria that are uniquely differentially expressed in MA. Conclusions: We conclude that high function in advanced age is associated with preserving mitochondrial structure/function proteins, with under-representation of proteins involved in the spliceosome and nuclear pore complex. Whereas many of these differences in MA appear related to their physical activity habits, others may reflect unique biological (e.g., gene, environment) mechanisms that preserve muscle integrity and function with aging. Funding: Funding for this study was provided by operating grants from the Canadian Institutes of Health Research (MOP 84408 to TT and MOP 125986 to RTH). Supported in part by the Intramural Research Program of the National Institute on Aging, NIH, Baltimore, MD, United States.
Collapse
Affiliation(s)
| | - Sally Spendiff
- Research Institute, Children's Hospital of Eastern Ontario, Ottawa, Canada
| | - Alexey Lyashkov
- Intramural Research Program, National Institute on Aging, Baltimore, United States
| | - Ruin Moaddel
- Intramural Research Program, National Institute on Aging, Baltimore, United States
| | | | | | | | - Tanja Taivassalo
- Department of Physical Therapy, University of Florida, Gainesville, United States
| | - Luigi Ferrucci
- Translational Gerentology Branch, National Institute on Aging, Baltimore, United States
| | - Russell T Hepple
- Department of Physical Therapy, University of Florida, Gainesville, United States
| |
Collapse
|
75
|
Komachi K, Burgess SM. The Nup2 meiotic-autonomous region relieves inhibition of Nup60 to promote progression of meiosis and sporulation in Saccharomyces cerevisiae. Genetics 2022; 221:6550504. [PMID: 35302609 PMCID: PMC9071577 DOI: 10.1093/genetics/iyac045] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 03/10/2022] [Indexed: 11/22/2022] Open
Abstract
During meiosis, chromosomes undergo dramatic changes in structural organization, nuclear positioning, and motion. Although the nuclear pore complex has been shown to affect genome organization and function in vegetative cells, its role in meiotic chromosome dynamics has remained largely unexplored. Recent work in the budding yeast Saccharomyces cerevisiae demonstrated that the mobile nucleoporin Nup2 is required for normal progression through meiosis I prophase and sporulation in strains where telomere-led chromosome movement has been compromised. The meiotic-autonomous region, a short fragment of Nup2 responsible for its role in meiosis, was shown to localize to the nuclear envelope via Nup60 and to bind to meiotic chromosomes. To understand the relative contribution these 2 activities have on meiotic-autonomous region function, we first carried out a screen for meiotic-autonomous region mutants defective in sporulation and found that all the mutations disrupt interaction with both Nup60 and meiotic chromosomes. Moreover, nup60 mutants phenocopy nup2 mutants, exhibiting similar nuclear division kinetics, sporulation efficiencies, and genetic interactions with mutations that affect the telomere bouquet. Although full-length Nup60 requires Nup2 for function, removal of Nup60's C-terminus allows Nup60 to bind meiotic chromosomes and promotes sporulation without Nup2. In contrast, binding of the meiotic-autonomous region to meiotic chromosomes is completely dependent on Nup60. Our findings uncover an inhibitory function for the Nup60 C-terminus and suggest that Nup60 mediates recruitment of meiotic chromosomes to the nuclear envelope, while Nup2 plays a secondary role counteracting the inhibitory function in Nup60's C-terminus.
Collapse
Affiliation(s)
- Kelly Komachi
- Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA 95616, USA
| | - Sean M Burgess
- Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA 95616, USA,Corresponding author: Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA 95616, USA.
| |
Collapse
|
76
|
Subcellular localization of X-linked inhibitor of apoptosis protein (XIAP) in cancer: does that matter? BBA ADVANCES 2022; 2:100050. [PMID: 37082602 PMCID: PMC10074912 DOI: 10.1016/j.bbadva.2022.100050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 02/25/2022] [Accepted: 03/15/2022] [Indexed: 11/20/2022] Open
Abstract
X-linked inhibitor of apoptosis protein (XIAP) finely tunes the balance between survival and death to control homeostasis. XIAP is found aberrantly expressed in cancer, which has been shown to promote resistance to therapy-induced apoptosis and confer poor outcome. Despite its predominant cytoplasmic localization in human tissues, growing evidence implicates the expression of XIAP in other subcellular compartments in sustaining cancer hallmarks. Herein, we review our current knowledge on the prognostic role of XIAP localization and discuss molecular mechanisms underlying differential biological functions played in each compartment. The comprehension of XIAP subcellular shuttling and functional dynamics might provide the rationale for future anticancer therapeutics.
Collapse
|
77
|
Raices M, D'Angelo MA. Structure, Maintenance, and Regulation of Nuclear Pore Complexes: The Gatekeepers of the Eukaryotic Genome. Cold Spring Harb Perspect Biol 2022; 14:a040691. [PMID: 34312247 PMCID: PMC8789946 DOI: 10.1101/cshperspect.a040691] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
In eukaryotic cells, the genetic material is segregated inside the nucleus. This compartmentalization of the genome requires a transport system that allows cells to move molecules across the nuclear envelope, the membrane-based barrier that surrounds the chromosomes. Nuclear pore complexes (NPCs) are the central component of the nuclear transport machinery. These large protein channels penetrate the nuclear envelope, creating a passage between the nucleus and the cytoplasm through which nucleocytoplasmic molecule exchange occurs. NPCs are one of the largest protein assemblies of eukaryotic cells and, in addition to their critical function in nuclear transport, these structures also play key roles in many cellular processes in a transport-independent manner. Here we will review the current knowledge of the NPC structure, the cellular mechanisms that regulate their formation and maintenance, and we will provide a brief description of a variety of processes that NPCs regulate.
Collapse
Affiliation(s)
- Marcela Raices
- Cell and Molecular Biology of Cancer Program, NCI-Designated Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California 92037, USA
| | - Maximiliano A D'Angelo
- Cell and Molecular Biology of Cancer Program, NCI-Designated Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California 92037, USA
| |
Collapse
|
78
|
Singh A, Verma S, Modak SB, Chaturvedi MM, Purohit JS. Extra-nuclear histones: origin, significance and perspectives. Mol Cell Biochem 2022; 477:507-524. [PMID: 34796445 DOI: 10.1007/s11010-021-04300-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 11/08/2021] [Indexed: 12/15/2022]
Abstract
Histones are classically known to organize the eukaryotic DNA into chromatin. They are one of the key players in regulating transcriptionally permissive and non-permissive states of the chromatin. Nevertheless, their context-dependent appearance within the cytoplasm and systemic circulation has also been observed. The past decade has also witnessed few scientific communications on the existence of vesicle-associated histones. Diverse groups have attempted to determine the significance of these extra-nuclear histones so far, with many of those studies still underway. Of note amongst these are interactions of extra-nuclear or free histones with cellular membranes, mediated by mutual cationic and anionic natures, respectively. It is here aimed to consolidate the mechanism of formation of extra-nuclear histones; implications of histone-induced membrane destabilization and explore the mechanisms of their association/release with extracellular vesicles, along with the functional aspects of these extra-nuclear histones in cell and systemic physiology.
Collapse
Affiliation(s)
- Abhilasha Singh
- Department of Zoology, University of Delhi, Delhi, 110007, India
| | - Sudhir Verma
- Department of Zoology, Deen Dayal Upadhyaya College, University of Delhi, Delhi, 110078, India
| | | | | | - Jogeswar S Purohit
- Department of Zoology, University of Delhi, Delhi, 110007, India.
- Molecular and Systems Biology Lab, Cluster Innovation Centre, University of Delhi, North Campus, DREAM Building, Delhi, 110007, India.
| |
Collapse
|
79
|
Cerrato CP, Langel Ü. An update on cell-penetrating peptides with intracellular organelle targeting. Expert Opin Drug Deliv 2022; 19:133-146. [PMID: 35086398 DOI: 10.1080/17425247.2022.2034784] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
INTRODUCTION Cell-penetrating peptide (CPP) technologies represent an important strategy to address drug delivery to specific intracellular compartments by covalent conjugation to targeting sequences, potentially enabling strategies to combat most diseases. AREAS COVERED This updated review article provides an overview of current intracellular organelle targeting by CPP. The targeting strategies of CPP and CPP/cargo complexes to specific cells or intracellular organelles are summarized, and the review provides an update on the current data for their pharmacological and therapeutical applications. EXPERT OPINION Targeted drug delivery is moving from the level of tissue or specific pathogenic cell to the level of specific organelle that is the target of the drug, an important aspect in drug design and development. Organelle-targeted drug delivery results in improved efficacy, ability to control mode of action, reduction of undesired toxicities and side effects, and possibility to overcome drug resistance mechanisms.
Collapse
Affiliation(s)
| | - Ülo Langel
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden.,Laboratory of Molecular Biotechnology, Institute of Technology, University of Tartu, Tartu, Estonia
| |
Collapse
|
80
|
Emerging Connections between Nuclear Pore Complex Homeostasis and ALS. Int J Mol Sci 2022; 23:ijms23031329. [PMID: 35163252 PMCID: PMC8835831 DOI: 10.3390/ijms23031329] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 01/17/2022] [Accepted: 01/20/2022] [Indexed: 12/26/2022] Open
Abstract
Developing effective treatments for neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS) requires understanding of the underlying pathomechanisms that contribute to the motor neuron loss that defines the disease. As it causes the largest fraction of familial ALS cases, considerable effort has focused on hexanucleotide repeat expansions in the C9ORF72 gene, which encode toxic repeat RNA and dipeptide repeat (DPR) proteins. Both the repeat RNA and DPRs interact with and perturb multiple elements of the nuclear transport machinery, including shuttling nuclear transport receptors, the Ran GTPase and the nucleoporin proteins (nups) that build the nuclear pore complex (NPC). Here, we consider recent work that describes changes to the molecular composition of the NPC in C9ORF72 model and patient neurons in the context of quality control mechanisms that function at the nuclear envelope (NE). For example, changes to NPC structure may be caused by the dysregulation of a conserved NE surveillance pathway mediated by the endosomal sorting complexes required for the transport protein, CHMP7. Thus, these studies are introducing NE and NPC quality control pathways as key elements in a pathological cascade that leads to C9ORF72 ALS, opening entirely new experimental avenues and possibilities for targeted therapeutic intervention.
Collapse
|
81
|
Abstract
The nuclear envelope is composed of the nuclear membranes, nuclear lamina, and nuclear pore complexes. Laminopathies are diseases caused by mutations in genes encoding protein components of the lamina and these other nuclear envelope substructures. Mutations in the single gene encoding lamin A and C, which are expressed in most differentiated somatic cells, cause diseases affecting striated muscle, adipose tissue, peripheral nerve, and multiple systems with features of accelerated aging. Mutations in genes encoding other nuclear envelope proteins also cause an array of diseases that selectively affect different tissues or organs. In some instances, the molecular and cellular consequences of laminopathy-causing mutations are known. However, even when these are understood, mechanisms explaining specific tissue or organ pathology remain enigmatic. Current mechanistic hypotheses focus on how alterations in the nuclear envelope may affect gene expression, including via the regulation of signaling pathways, or cellular mechanics, including responses to mechanical stress.
Collapse
Affiliation(s)
- Ji-Yeon Shin
- Department of Medicine and Department of Pathology and Cell Biology, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
| | - Howard J. Worman
- Department of Medicine and Department of Pathology and Cell Biology, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
| |
Collapse
|
82
|
Luchinat E, Cremonini M, Banci L. Radio Signals from Live Cells: The Coming of Age of In-Cell Solution NMR. Chem Rev 2022; 122:9267-9306. [PMID: 35061391 PMCID: PMC9136931 DOI: 10.1021/acs.chemrev.1c00790] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
![]()
A detailed knowledge
of the complex processes that make cells and
organisms alive is fundamental in order to understand diseases and
to develop novel drugs and therapeutic treatments. To this aim, biological
macromolecules should ideally be characterized at atomic resolution
directly within the cellular environment. Among the existing structural
techniques, solution NMR stands out as the only one able to investigate
at high resolution the structure and dynamic behavior of macromolecules
directly in living cells. With the advent of more sensitive NMR hardware
and new biotechnological tools, modern in-cell NMR approaches have
been established since the early 2000s. At the coming of age of in-cell
NMR, we provide a detailed overview of its developments and applications
in the 20 years that followed its inception. We review the existing
approaches for cell sample preparation and isotopic labeling, the
application of in-cell NMR to important biological questions, and
the development of NMR bioreactor devices, which greatly increase
the lifetime of the cells allowing real-time monitoring of intracellular
metabolites and proteins. Finally, we share our thoughts on the future
perspectives of the in-cell NMR methodology.
Collapse
Affiliation(s)
- Enrico Luchinat
- Dipartimento di Scienze e Tecnologie Agro-Alimentari, Alma Mater Studiorum−Università di Bologna, Piazza Goidanich 60, 47521 Cesena, Italy
- Magnetic Resonance Center, Università degli Studi di Firenze, Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Italy
| | - Matteo Cremonini
- Magnetic Resonance Center, Università degli Studi di Firenze, Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Italy
| | - Lucia Banci
- Magnetic Resonance Center, Università degli Studi di Firenze, Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Italy
- Consorzio Interuniversitario Risonanze Magnetiche di Metallo Proteine, Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Italy
- Dipartimento di Chimica, Università degli Studi di Firenze, Via della Lastruccia 3, 50019 Sesto Fiorentino, Italy
| |
Collapse
|
83
|
Unconventional metabolites in chromatin regulation. Biosci Rep 2022; 42:230604. [PMID: 34988581 PMCID: PMC8777195 DOI: 10.1042/bsr20211558] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 01/04/2022] [Accepted: 01/04/2022] [Indexed: 11/17/2022] Open
Abstract
Chromatin, the complex of DNA and histone proteins, serves as a main integrator of cellular signals. Increasing evidence links cellular functional to chromatin state. Indeed, different metabolites are emerging as modulators of chromatin function and structure. Alterations in chromatin state are decisive for regulating all aspects of genome function and ultimately have the potential to produce phenotypic changes. Several metabolites such as acetyl-CoA, S-adenosylmethionine (SAM) or adenosine triphosphate (ATP) have now been well characterized as main substrates or cofactors of chromatin-modifying enzymes. However, there are other metabolites that can directly interact with chromatin influencing its state or that modulate the properties of chromatin regulatory factors. Also, there is a growing list of atypical enzymatic and nonenzymatic chromatin modifications that originate from different cellular pathways that have not been in the limelight of chromatin research. Here, we summarize different properties and functions of uncommon regulatory molecules originating from intermediate metabolism of lipids, carbohydrates and amino acids. Based on the various modes of action on chromatin and the plethora of putative, so far not described chromatin-regulating metabolites, we propose that there are more links between cellular functional state and chromatin regulation to be discovered. We hypothesize that these connections could provide interesting starting points for interfering with cellular epigenetic states at a molecular level.
Collapse
|
84
|
Raices M, D'Angelo MA. Analysis of Nuclear Pore Complex Permeability in Mammalian Cells and Isolated Nuclei Using Fluorescent Dextrans. Methods Mol Biol 2022; 2502:69-80. [PMID: 35412231 PMCID: PMC9278988 DOI: 10.1007/978-1-0716-2337-4_4] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
In eukaryotic cells the nuclear envelope encloses the genome separating it from the rest of the cell. Nuclear pore complexes are large multi protein channels that perforate the nuclear envelope, connecting the nucleus and the cytoplasm. Besides controlling nucleocytoplasmic molecule exchange, nuclear pore complexes create a permeability barrier that defines the maximum size of molecules that can freely diffuse into the nucleus. Accumulating evidence indicate that the permeability barrier of the nucleus can vary in different cellular conditions, during aging and in disease. Here we provide a simple protocol to analyze changes in nuclear permeability in plasma membrane-permeabilized cells and isolated nuclei using fluorescent dextrans of different sizes and confocal microscopy. The methods described herein represent a valuable resource to researchers studying the function of nuclear pore complexes and the dynamics of nuclear permeability in different cell types and processes.
Collapse
Affiliation(s)
- Marcela Raices
- Cellular and Molecular Biology of Cancer Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, USA
- NCI-Designated Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, USA
| | - Maximiliano A D'Angelo
- Cellular and Molecular Biology of Cancer Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, USA.
- NCI-Designated Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, USA.
| |
Collapse
|
85
|
Schnell SJ, Tingey M, Yang W. Speed Microscopy: High-Speed Single Molecule Tracking and Mapping of Nucleocytoplasmic Transport. Methods Mol Biol 2022; 2502:353-371. [PMID: 35412250 PMCID: PMC10131132 DOI: 10.1007/978-1-0716-2337-4_23] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The nuclear pore complex (NPC) functions as a gateway through which molecules translocate into and out of the nucleus. Understanding the transport dynamics of these transiting molecules and how they interact with the NPC has great potentials in the discovery of clinical targets. Single-molecule microscopy techniques are powerful tools to provide sub-diffraction limit information about the dynamic and structural details of nucleocytoplasmic transport. Here we detail single-point edge-excitation subdiffraction (SPEED) microscopy, a high-speed superresolution microscopy technique designed to track and map proteins and RNAs as they cross native NPCs.
Collapse
Affiliation(s)
| | - Mark Tingey
- Department of Biology, Temple University, Philadelphia, PA, USA
| | - Weidong Yang
- Department of Biology, Temple University, Philadelphia, PA, USA.
| |
Collapse
|
86
|
Bindra D, Mishra RK. In Pursuit of Distinctiveness: Transmembrane Nucleoporins and Their Disease Associations. Front Oncol 2022; 11:784319. [PMID: 34970494 PMCID: PMC8712647 DOI: 10.3389/fonc.2021.784319] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 11/25/2021] [Indexed: 11/13/2022] Open
Abstract
The bi-directional nucleocytoplasmic shuttling of macromolecules like molecular signals, transcription factors, regulatory proteins, and RNAs occurs exclusively through Nuclear Pore Complex (NPC) residing in the nuclear membrane. This magnanimous complex is essentially a congregation of ~32 conserved proteins termed Nucleoporins (Nups) present in multiple copies and mostly arranged as subcomplexes to constitute a functional NPC. Nups participate in ancillary functions such as chromatin organization, transcription regulation, DNA damage repair, genome stabilization, and cell cycle control, apart from their central role as nucleocytoplasmic conduits. Thus, Nups exert a role in the maintenance of cellular homeostasis. In mammals, precisely three nucleoporins traverse the nuclear membrane, are called transmembrane Nups (TM-Nups), and are involved in multiple cellular functions. Owing to their vital roles in cellular processes and homeostasis, dysregulation of nucleoporin function is implicated in various diseases. The deregulated functioning of TM-Nups can thus act as an opportune window for the development of diseases. Indeed, mounting evidence exhibits a strong association of TM-Nups in cancer and numerous other physiological disorders. These findings have provided much-needed insights into the novel mechanisms of disease progression. While nucleoporin’s functions have often been summarized in the disease context, a focus on TM-Nups has always lacked. This review emphasizes the elucidation of distinct canonical and non-canonical functions of mammalian TM-Nups and the underlying mechanisms of their disease association.
Collapse
Affiliation(s)
- Divya Bindra
- Nups and SUMO Biology Group, Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Bhopal, Bhopal, India
| | - Ram Kumar Mishra
- Nups and SUMO Biology Group, Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Bhopal, Bhopal, India
| |
Collapse
|
87
|
Albarnaz JD, Ren H, Torres AA, Shmeleva EV, Melo CA, Bannister AJ, Brember MP, Chung BYW, Smith GL. Molecular mimicry of NF-κB by vaccinia virus protein enables selective inhibition of antiviral responses. Nat Microbiol 2022; 7:154-168. [PMID: 34949827 PMCID: PMC7614822 DOI: 10.1038/s41564-021-01004-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2020] [Accepted: 10/21/2021] [Indexed: 12/16/2022]
Abstract
Infection of mammalian cells with viruses activates NF-κB to induce the expression of cytokines and chemokines and initiate an antiviral response. Here, we show that a vaccinia virus protein mimics the transactivation domain of the p65 subunit of NF-κB to inhibit selectively the expression of NF-κB-regulated genes. Using co-immunoprecipitation assays, we found that the vaccinia virus protein F14 associates with NF-κB co-activator CREB-binding protein (CBP) and disrupts the interaction between p65 and CBP. This abrogates CBP-mediated acetylation of p65, after which it reduces promoter recruitment of the transcriptional regulator BRD4 and diminishes stimulation of NF-κB-regulated genes CXCL10 and CCL2. Recruitment of BRD4 to the promoters of NFKBIA and CXCL8 remains unaffected by either F14 or JQ1 (a competitive inhibitor of BRD4 bromodomains), indicating that BRD4 recruitment is acetylation-independent. Unlike other viral proteins that are general antagonists of NF-κB, F14 is a selective inhibitor of NF-κB-dependent gene expression. An in vivo model of infection demonstrated that F14 promotes virulence. Molecular mimicry of NF-κB may be conserved because other orthopoxviruses, including variola, monkeypox and cowpox viruses, encode orthologues of F14.
Collapse
Affiliation(s)
- Jonas D Albarnaz
- Department of Pathology, University of Cambridge, Cambridge, UK.
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK.
| | - Hongwei Ren
- Department of Pathology, University of Cambridge, Cambridge, UK
- Department of Immunology and Inflammation, Imperial College London, Hammersmith Campus, London, UK
| | - Alice A Torres
- Department of Pathology, University of Cambridge, Cambridge, UK
| | - Evgeniya V Shmeleva
- Department of Pathology, University of Cambridge, Cambridge, UK
- Department of Obstetrics and Gynaecology, University of Cambridge, Cambridge, UK
| | - Carlos A Melo
- The Gurdon Institute, University of Cambridge, Cambridge, UK
| | | | | | - Betty Y-W Chung
- Department of Pathology, University of Cambridge, Cambridge, UK
| | - Geoffrey L Smith
- Department of Pathology, University of Cambridge, Cambridge, UK.
| |
Collapse
|
88
|
Bauer M, Gomez-Gonzalez A, Suomalainen M, Schilling N, Hemmi S, Greber UF. A viral ubiquitination switch attenuates innate immunity and triggers nuclear import of virion DNA and infection. SCIENCE ADVANCES 2021; 7:eabl7150. [PMID: 34919430 PMCID: PMC8682987 DOI: 10.1126/sciadv.abl7150] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Antiviral defense and virus exclusion from the cell nucleus restrict foreign nucleic acid influx and infection. How the genomes of DNA viruses evade cytosolic pattern recognition and cross the nuclear envelope is incompletely understood. Here, we show that the virion protein V of adenovirus functions as a linchpin between the genome and the capsid, thereby securing particle integrity. Absence of protein V destabilizes cytoplasmic particles and promotes premature genome release, raising cytokine levels through the DNA sensor cGAS. Non-ubiquitinable V yields stable virions, genome misdelivery to the cytoplasm, and increased cytokine levels. In contrast, normal protein V is ubiquitinated at the nuclear pore complex, dissociates from the virion depending on the E3 ubiquitin ligase Mib1 and the proteasome, and allows genome delivery into the nucleus for infection. Our data uncover previously unknown cellular and viral mechanisms of viral DNA nuclear import in pathogenesis, vaccination, gene therapy, and synthetic biology.
Collapse
Affiliation(s)
- Michael Bauer
- Department of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, Zurich CH8057, Switzerland
| | - Alfonso Gomez-Gonzalez
- Department of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, Zurich CH8057, Switzerland
- Life Science Zurich Graduate School, ETH and University of Zurich, Zurich 8057, Switzerland
| | - Maarit Suomalainen
- Department of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, Zurich CH8057, Switzerland
| | - Nicolas Schilling
- Center for Microscopy and Image Analysis, University of Zurich, Winterthurerstrasse 190, Zurich CH-8057, Switzerland
| | - Silvio Hemmi
- Department of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, Zurich CH8057, Switzerland
| | - Urs F. Greber
- Department of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, Zurich CH8057, Switzerland
- Corresponding author.
| |
Collapse
|
89
|
Petrů M, Dohnálek V, Füssy Z, Doležal P. Fates of Sec, Tat, and YidC Translocases in Mitochondria and Other Eukaryotic Compartments. Mol Biol Evol 2021; 38:5241-5254. [PMID: 34436602 PMCID: PMC8662606 DOI: 10.1093/molbev/msab253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Formation of mitochondria by the conversion of a bacterial endosymbiont was a key moment in the evolution of eukaryotes. It was made possible by outsourcing the endosymbiont's genetic control to the host nucleus, while developing the import machinery for proteins synthesized on cytosolic ribosomes. The original protein export machines of the nascent organelle remained to be repurposed or were completely abandoned. This review follows the evolutionary fates of three prokaryotic inner membrane translocases Sec, Tat, and YidC. Homologs of all three translocases can still be found in current mitochondria, but with different importance for mitochondrial function. Although the mitochondrial YidC homolog, Oxa1, became an omnipresent independent insertase, the other two remained only sporadically present in mitochondria. Only a single substrate is known for the mitochondrial Tat and no function has yet been assigned for the mitochondrial Sec. Finally, this review compares these ancestral mitochondrial proteins with their paralogs operating in the plastids and the endomembrane system.
Collapse
Affiliation(s)
- Markéta Petrů
- Department of Parasitology, Faculty of Science, Charles University, BIOCEV, Vestec, Czech Republic
| | - Vít Dohnálek
- Department of Parasitology, Faculty of Science, Charles University, BIOCEV, Vestec, Czech Republic
| | - Zoltán Füssy
- Department of Parasitology, Faculty of Science, Charles University, BIOCEV, Vestec, Czech Republic
| | - Pavel Doležal
- Department of Parasitology, Faculty of Science, Charles University, BIOCEV, Vestec, Czech Republic
| |
Collapse
|
90
|
Chandra S, Mannino PJ, Thaller DJ, Ader NR, King MC, Melia TJ, Lusk CP. Atg39 selectively captures inner nuclear membrane into lumenal vesicles for delivery to the autophagosome. J Cell Biol 2021; 220:e202103030. [PMID: 34714326 PMCID: PMC8575018 DOI: 10.1083/jcb.202103030] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 08/26/2021] [Accepted: 09/29/2021] [Indexed: 12/26/2022] Open
Abstract
Mechanisms that turn over components of the nucleus and inner nuclear membrane (INM) remain to be fully defined. We explore how components of the INM are selected by a cytosolic autophagy apparatus through a transmembrane nuclear envelope-localized cargo adaptor, Atg39. A split-GFP reporter showed that Atg39 localizes to the outer nuclear membrane (ONM) and thus targets the INM across the nuclear envelope lumen. Consistent with this, sequence elements that confer both nuclear envelope localization and a membrane remodeling activity are mapped to the Atg39 lumenal domain; these lumenal motifs are required for the autophagy-mediated degradation of integral INM proteins. Interestingly, correlative light and electron microscopy shows that the overexpression of Atg39 leads to the expansion of the ONM and the enclosure of a network of INM-derived vesicles in the nuclear envelope lumen. Thus, we propose an outside-in model of nucleophagy where INM is delivered into vesicles in the nuclear envelope lumen, which can be targeted by the autophagosome.
Collapse
Affiliation(s)
| | | | | | | | | | - Thomas J. Melia
- Department of Cell Biology, Yale School of Medicine, New Haven, CT
| | - C. Patrick Lusk
- Department of Cell Biology, Yale School of Medicine, New Haven, CT
| |
Collapse
|
91
|
Mirsalehi A, Markova DN, Eslamieh M, Betrán E. Nuclear transport genes recurrently duplicate by means of RNA intermediates in Drosophila but not in other insects. BMC Genomics 2021; 22:876. [PMID: 34863092 PMCID: PMC8645118 DOI: 10.1186/s12864-021-08170-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 11/08/2021] [Indexed: 11/16/2022] Open
Abstract
Background The nuclear transport machinery is involved in a well-known male meiotic drive system in Drosophila. Fast gene evolution and gene duplications have been major underlying mechanisms in the evolution of meiotic drive systems, and this might include some nuclear transport genes in Drosophila. So, using a comprehensive, detailed phylogenomic study, we examined 51 insect genomes for the duplication of the same nuclear transport genes. Results We find that most of the nuclear transport duplications in Drosophila are of a few classes of nuclear transport genes, RNA mediated and fast evolving. We also retrieve many pseudogenes for the Ran gene. Some of the duplicates are relatively young and likely contributing to the turnover expected for genes under strong but changing selective pressures. These duplications are potentially revealing what features of nuclear transport are under selection. Unlike in flies, we find only a few duplications when we study the Drosophila duplicated nuclear transport genes in dipteran species outside of Drosophila, and none in other insects. Conclusions These findings strengthen the hypothesis that nuclear transport gene duplicates in Drosophila evolve either as drivers or suppressors of meiotic drive systems or as other male-specific adaptations circumscribed to flies and involving a handful of nuclear transport functions. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-021-08170-4.
Collapse
Affiliation(s)
- Ayda Mirsalehi
- Department of Biology, The University of Texas at Arlington, Box 19498, Arlington, TX, 76019, USA
| | - Dragomira N Markova
- Department of Biology, The University of Texas at Arlington, Box 19498, Arlington, TX, 76019, USA
| | - Mohammadmehdi Eslamieh
- Department of Biology, The University of Texas at Arlington, Box 19498, Arlington, TX, 76019, USA
| | - Esther Betrán
- Department of Biology, The University of Texas at Arlington, Box 19498, Arlington, TX, 76019, USA.
| |
Collapse
|
92
|
Boon R. Metabolic Fuel for Epigenetic: Nuclear Production Meets Local Consumption. Front Genet 2021; 12:768996. [PMID: 34804127 PMCID: PMC8595138 DOI: 10.3389/fgene.2021.768996] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 10/20/2021] [Indexed: 12/28/2022] Open
Abstract
Epigenetic modifications are responsible for finetuning gene expression profiles to the needs of cells, tissues, and organisms. To rapidly respond to environmental changes, the activity of chromatin modifiers critically depends on the concentration of a handful of metabolites that act as substrates and co-factors. In this way, these enzymes act as metabolic sensors that directly link gene expression to metabolic states. Although metabolites can easily diffuse through the nuclear pore, molecular mechanisms must be in place to regulate epigenetic marker deposition in specific nuclear subdomains or even on single loci. In this review, I explore the possible subcellular sites of metabolite production that influence the epigenome. From the relationship between cytoplasmic metabolism and nuclear metabolite deposition, I converse to the description of a compartmentalized nuclear metabolism. Last, I elaborate on the possibility of metabolic enzymes to operate in phase-separated nuclear microdomains formed by multienzyme and chromatin-bound protein complexes.
Collapse
Affiliation(s)
- Ruben Boon
- The Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA, United States.,The Broad Institute of Harvard and MIT, Cambridge, MA, United States.,Laboratory for Functional Epigenetics, Department of Human Genetics, KU Leuven, Leuven, Belgium
| |
Collapse
|
93
|
Nuclear pore complex maintenance and implications for age-related diseases. Trends Cell Biol 2021; 32:216-227. [PMID: 34782239 DOI: 10.1016/j.tcb.2021.10.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 10/04/2021] [Accepted: 10/07/2021] [Indexed: 12/31/2022]
Abstract
Nuclear pore complexes (NPCs) bridge the nucleus and the cytoplasm and are indispensable for crucial cellular activities, such as bidirectional molecular trafficking and gene transcription regulation. The discovery of long-lived proteins (LLPs) in NPCs from postmitotic cells raises the exciting possibility that the maintenance of NPC integrity might play an inherent role in lifelong cell function. Age-dependent deterioration of NPCs and loss of nuclear integrity have been linked to age-related decline in postmitotic cell function and degenerative diseases. In this review, we discuss our current understanding of NPC maintenance in proliferating and postmitotic cells, and how malfunction of nucleoporins (Nups) might contribute to the pathogenesis of various neurodegenerative and cardiovascular diseases.
Collapse
|
94
|
Torres P, Cabral-Miranda F, Gonzalez-Teuber V, Hetz C. Proteostasis deregulation as a driver of C9ORF72 pathogenesis. J Neurochem 2021; 159:941-957. [PMID: 34679204 DOI: 10.1111/jnc.15529] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Revised: 10/16/2021] [Accepted: 10/18/2021] [Indexed: 12/21/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are two related neurodegenerative disorders that display overlapping features. The hexanucleotide repeat expansion GGGGCC (G4 C2 ) in C9ORF72 gene has been causally linked to both ALS and FTD emergence, thus opening a novel potential therapeutic target for disease intervention. The main driver of C9ORF72 pathology is the disruption of distinct cellular processes involved in the function of the proteostasis network. Here we discuss main findings relating to the induction of neurodegeneration by C9ORF72 mutation and proteostasis deregulation, highlighting the role of the endoplasmic reticulum stress, nuclear transport, and autophagy in the disease process. We further discuss possible points of intervention to target proteostasis mediators to treat C9ORF72-linked ALS/FTD.
Collapse
Affiliation(s)
- Paulina Torres
- Biomedical Neuroscience Institute (BNI), Faculty of Medicine, University of Chile, Santiago, Chile.,FONDAP Center for Geroscience, Brain Health, and Metabolism (GERO), Santiago, Chile.,Program of Cellular and Molecular Biology, Institute of Biomedical Science, University of Chile, Santiago, Chile
| | - Felipe Cabral-Miranda
- Instituto de Ciências Biomédicas, Universidade do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Vicente Gonzalez-Teuber
- Biomedical Neuroscience Institute (BNI), Faculty of Medicine, University of Chile, Santiago, Chile.,FONDAP Center for Geroscience, Brain Health, and Metabolism (GERO), Santiago, Chile.,Program of Cellular and Molecular Biology, Institute of Biomedical Science, University of Chile, Santiago, Chile
| | - Claudio Hetz
- Biomedical Neuroscience Institute (BNI), Faculty of Medicine, University of Chile, Santiago, Chile.,FONDAP Center for Geroscience, Brain Health, and Metabolism (GERO), Santiago, Chile.,Program of Cellular and Molecular Biology, Institute of Biomedical Science, University of Chile, Santiago, Chile.,Buck Institute for Research on Aging, Novato, California, USA
| |
Collapse
|
95
|
Therapeutic strategies for C9orf72 amyotrophic lateral sclerosis and frontotemporal dementia. Curr Opin Neurol 2021; 34:748-755. [PMID: 34392299 PMCID: PMC8678157 DOI: 10.1097/wco.0000000000000984] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE OF REVIEW An intronic G4C2 expansion mutation in C9orf72 is the most common genetic cause of amyotrophic lateral sclerosis and frontotemporal dementia (C9-ALS/FTD). Although there are currently no treatments for this insidious, fatal disease, intense research has led to promising therapeutic strategies, which will be discussed here. RECENT FINDINGS Therapeutic strategies for C9-ALS/FTD have primarily focused on reducing the toxic effects of mutant expansion RNAs or the dipeptide repeat proteins (DPRs). The pathogenic effects of G4C2 expansion transcripts have been targeted using approaches aimed at promoting their degradation, inhibiting nuclear export or silencing transcription. Other promising strategies include immunotherapy to reduce the DPRs themselves, reducing RAN translation, removing the repeats using DNA or RNA editing and manipulation of downstream disease-altered stress granule pathways. Finally, understanding the molecular triggers that lead to pheno-conversion may lead to opportunities that can delay symptomatic disease onset. SUMMARY A large body of evidence implicates RAN-translated DPRs as a main driver of C9-ALS/FTD. Promising therapeutic strategies for these devastating diseases are being rapidly developed with several approaches already in or approaching clinical trials.
Collapse
|
96
|
Recent advances in active targeting of nanomaterials for anticancer drug delivery. Adv Colloid Interface Sci 2021; 296:102509. [PMID: 34455211 DOI: 10.1016/j.cis.2021.102509] [Citation(s) in RCA: 63] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Revised: 07/24/2021] [Accepted: 08/15/2021] [Indexed: 12/15/2022]
Abstract
One of the challenges in cancer chemotherapy is the low target to non-target ratio of therapeutic agents which incur severe adverse effect on the healthy tissues. In this regard, nanomaterials have tremendous potential for impacting cancer therapy by altering the toxicity profile of the drug. Some of the striking advantages provided by the nanocarriers mediated targeted drug delivery are relatively high build-up of drug concentration at the tumor site, improved drug content in the formulation and enhanced colloidal stability. Further, nanocarriers with tumor-specific moieties can be targeted to the cancer cell through cell surface receptors, tumor antigens and tumor vasculatures with high affinity and accuracy. Moreover, it overcomes the bottleneck of aimless drug biodistribution, undesired toxicity and heavy dosage of administration. This review discusses the recent developments in active targeting of nanomaterials for anticancer drug delivery through cancer cell surface targeting, organelle specific targeting and tumor microenvironment targeting strategies. Special emphasis has been given towards cancer cell surface and organelle specific targeting as delivery of anticancer drugs through these routes have made paradigm change in cancer management. Further, the current challenges and future prospects of nanocarriers mediated active drug targeting are also demonstrated.
Collapse
|
97
|
Lange J, Wood-Kaczmar A, Ali A, Farag S, Ghosh R, Parker J, Casey C, Uno Y, Kunugi A, Ferretti P, Andre R, Tabrizi SJ. Mislocalization of Nucleocytoplasmic Transport Proteins in Human Huntington's Disease PSC-Derived Striatal Neurons. Front Cell Neurosci 2021; 15:742763. [PMID: 34658796 PMCID: PMC8519404 DOI: 10.3389/fncel.2021.742763] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Accepted: 09/09/2021] [Indexed: 11/17/2022] Open
Abstract
Huntington's disease (HD) is an inherited neurodegenerative disorder caused by a CAG repeat expansion in the huntingtin gene (HTT). Disease progression is characterized by the loss of vulnerable neuronal populations within the striatum. A consistent phenotype across HD models is disruption of nucleocytoplasmic transport and nuclear pore complex (NPC) function. Here we demonstrate that high content imaging is a suitable method for detecting mislocalization of lamin-B1, RAN and RANGAP1 in striatal neuronal cultures thus allowing a robust, unbiased, highly powered approach to assay nuclear pore deficits. Furthermore, nuclear pore deficits extended to the selectively vulnerable DARPP32 + subpopulation neurons, but not to astrocytes. Striatal neuron cultures are further affected by changes in gene and protein expression of RAN, RANGAP1 and lamin-B1. Lowering total HTT using HTT-targeted anti-sense oligonucleotides partially restored gene expression, as well as subtly reducing mislocalization of proteins involved in nucleocytoplasmic transport. This suggests that mislocalization of RAN, RANGAP1 and lamin-B1 cannot be normalized by simply reducing expression of CAG-expanded HTT in the absence of healthy HTT protein.
Collapse
Affiliation(s)
- Jenny Lange
- Huntington’s Disease Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Alison Wood-Kaczmar
- Huntington’s Disease Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Aneesa Ali
- Huntington’s Disease Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Sahar Farag
- Huntington’s Disease Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Rhia Ghosh
- Huntington’s Disease Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Jennifer Parker
- Huntington’s Disease Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Caroline Casey
- Huntington’s Disease Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Yumiko Uno
- Neuroscience Drug Discovery Unit, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Akiyoshi Kunugi
- Neuroscience Drug Discovery Unit, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Patrizia Ferretti
- Stem Cell and Regenerative Medicine Section, UCL Great Ormond Street Institute of Child Health, London, United Kingdom
| | - Ralph Andre
- Huntington’s Disease Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Sarah J. Tabrizi
- Huntington’s Disease Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
- UK Dementia Research Institute, University College London, London, United Kingdom
| |
Collapse
|
98
|
Miron A, Mukamel D, Posch HA. Attraction and condensation of driven tracers in a narrow channel. Phys Rev E 2021; 104:024123. [PMID: 34525576 DOI: 10.1103/physreve.104.024123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Accepted: 07/28/2021] [Indexed: 11/07/2022]
Abstract
Emergent bath-mediated attraction and condensation arise when multiple particles are simultaneously driven through an equilibrated bath under geometric constraints. While such scenarios are observed in a variety of nonequilibrium phenomena with an abundance of experimental and numerical evidence, little quantitative understanding of how these interactions arise is currently available. Here we approach the problem by studying the behavior of two driven "tracer" particles, propagating through a bath in a 1D lattice with excluded-volume interactions. We apply the mean-field approximation to analytically explore the mechanism responsible for the tracers' emergent interactions and compute the resulting effective attractive potential. This mechanism is then numerically shown to extend to a realistic model of hard driven Brownian disks confined to a narrow 2D channel.
Collapse
Affiliation(s)
- Asaf Miron
- Department of Physics of Complex Systems, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - David Mukamel
- Department of Physics of Complex Systems, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Harald A Posch
- Computational Physics Group, Faculty of Physics, University of Vienna, Vienna 1090, Austria
| |
Collapse
|
99
|
Matsuda A, Mofrad MRK. Free energy calculations shed light on the nuclear pore complex's selective barrier nature. Biophys J 2021; 120:3628-3640. [PMID: 34339633 PMCID: PMC8456294 DOI: 10.1016/j.bpj.2021.07.025] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 05/27/2021] [Accepted: 07/27/2021] [Indexed: 12/27/2022] Open
Abstract
The nuclear pore complex (NPC) is the exclusive gateway for traffic control across the nuclear envelope. Although smaller cargoes (less than 5-9 nm in size) can freely diffuse through the NPC, the passage of larger cargoes is restricted to those accompanied by nuclear transport receptors (NTRs). This selective barrier nature of the NPC is putatively associated with the intrinsically disordered, phenylalanine-glycine repeat-domains containing nucleoporins, termed FG-Nups. The precise mechanism underlying how FG-Nups carry out such an exquisite task at high throughputs has, however, remained elusive and the subject of various hypotheses. From the thermodynamics perspective, free energy analysis can be a way to determine cargo's transportability because the traffic through the NPC must be in the direction of reducing the free energy. In this study, we developed a computational model to evaluate the free energy composed of the conformational entropy of FG-Nups and the energetic gain associated with binding interactions between FG-Nups and NTRs and investigated whether these physical features can be the basis of NPC's selectivity. Our results showed that the reduction in conformational entropy by inserting a cargo into the NPC increased the free energy by an amount substantially greater than the thermal energy (≫kBT), whereas the free energy change was negligible (
Collapse
Affiliation(s)
- Atsushi Matsuda
- Molecular Cell Biomechanics Laboratory, Departments of Bioengineering and Mechanical Engineering, University of California Berkeley, Berkeley, California
| | - Mohammad R K Mofrad
- Molecular Cell Biomechanics Laboratory, Departments of Bioengineering and Mechanical Engineering, University of California Berkeley, Berkeley, California; Molecular Biophysics and Integrative Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California.
| |
Collapse
|
100
|
Alston JJ, Soranno A, Holehouse AS. Integrating single-molecule spectroscopy and simulations for the study of intrinsically disordered proteins. Methods 2021; 193:116-135. [PMID: 33831596 PMCID: PMC8713295 DOI: 10.1016/j.ymeth.2021.03.018] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 03/25/2021] [Accepted: 03/31/2021] [Indexed: 12/21/2022] Open
Abstract
Over the last two decades, intrinsically disordered proteins and protein regions (IDRs) have emerged from a niche corner of biophysics to be recognized as essential drivers of cellular function. Various techniques have provided fundamental insight into the function and dysfunction of IDRs. Among these techniques, single-molecule fluorescence spectroscopy and molecular simulations have played a major role in shaping our modern understanding of the sequence-encoded conformational behavior of disordered proteins. While both techniques are frequently used in isolation, when combined they offer synergistic and complementary information that can help uncover complex molecular details. Here we offer an overview of single-molecule fluorescence spectroscopy and molecular simulations in the context of studying disordered proteins. We discuss the various means in which simulations and single-molecule spectroscopy can be integrated, and consider a number of studies in which this integration has uncovered biological and biophysical mechanisms.
Collapse
Affiliation(s)
- Jhullian J Alston
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis 63110, MO, USA; Center for Science and Engineering of Living Systems (CSELS), Washington University in St. Louis, St. Louis 63130, MO, USA
| | - Andrea Soranno
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis 63110, MO, USA; Center for Science and Engineering of Living Systems (CSELS), Washington University in St. Louis, St. Louis 63130, MO, USA.
| | - Alex S Holehouse
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis 63110, MO, USA; Center for Science and Engineering of Living Systems (CSELS), Washington University in St. Louis, St. Louis 63130, MO, USA.
| |
Collapse
|