1
|
Quinlan RA, Schwarz N, Windoffer R, Richardson C, Hawkins T, Broussard JA, Green KJ, Leube RE. A rim-and-spoke hypothesis to explain the biomechanical roles for cytoplasmic intermediate filament networks. J Cell Sci 2018; 130:3437-3445. [PMID: 29032358 DOI: 10.1242/jcs.202168] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 08/02/2017] [Indexed: 12/17/2022] Open
Abstract
Textbook images of keratin intermediate filament (IF) networks in epithelial cells and the functional compromization of the epidermis by keratin mutations promulgate a mechanical role for this important cytoskeletal component. In stratified epithelia, keratin filaments form prominent radial spokes that are focused onto cell-cell contact sites, i.e. the desmosomes. In this Hypothesis, we draw attention to a subset of keratin filaments that are apposed to the plasma membrane. They form a rim of filaments interconnecting the desmosomes in a circumferential network. We hypothesize that they are part of a rim-and-spoke arrangement of IFs in epithelia. From our review of the literature, we extend this functional role for the subplasmalemmal rim of IFs to any cell, in which plasma membrane support is required, provided these filaments connect directly or indirectly to the plasma membrane. Furthermore, cytoplasmic IF networks physically link the outer nuclear and plasma membranes, but their participation in mechanotransduction processes remain largely unconsidered. Therefore, we also discuss the potential biomechanical and mechanosensory role(s) of the cytoplasmic IF network in terms of such a rim (i.e. subplasmalemmal)-and-spoke arrangement for cytoplasmic IF networks.
Collapse
Affiliation(s)
- Roy A Quinlan
- Department of Biosciences, University of Durham, Upper Mountjoy, Stockton Road, Durham DH1 3LE, UK .,Biophysical Sciences Institute, University of Durham, Upper Mountjoy, Stockton Road, Durham DH1 3LE, UK
| | - Nicole Schwarz
- RWTH Aachen University, Institute of Molecular and Cellular Anatomy, Wendlingweg 2, 52074 Aachen, Germany
| | - Reinhard Windoffer
- RWTH Aachen University, Institute of Molecular and Cellular Anatomy, Wendlingweg 2, 52074 Aachen, Germany
| | - Christine Richardson
- Department of Biosciences, University of Durham, Upper Mountjoy, Stockton Road, Durham DH1 3LE, UK
| | - Tim Hawkins
- Department of Biosciences, University of Durham, Upper Mountjoy, Stockton Road, Durham DH1 3LE, UK
| | - Joshua A Broussard
- Dept. of Pathology W127, Tarry Bldg, Room 3-735, Northwestern University, Feinberg School of Medicine, 303 E. Chicago Ave., Chicago, IL 60611, USA
| | - Kathleen J Green
- Dept. of Pathology W127, Tarry Bldg, Room 3-735, Northwestern University, Feinberg School of Medicine, 303 E. Chicago Ave., Chicago, IL 60611, USA
| | - Rudolf E Leube
- RWTH Aachen University, Institute of Molecular and Cellular Anatomy, Wendlingweg 2, 52074 Aachen, Germany
| |
Collapse
|
2
|
Iwatsuki H, Suda M. Seven kinds of intermediate filament networks in the cytoplasm of polarized cells: structure and function. Acta Histochem Cytochem 2010; 43:19-31. [PMID: 20514289 PMCID: PMC2875862 DOI: 10.1267/ahc.10009] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2010] [Accepted: 03/15/2010] [Indexed: 02/01/2023] Open
Abstract
Intermediate filaments (IFs) are involved in many important physiological functions, such as the distribution of organelles, signal transduction, cell polarity and gene regulation. However, little information exists on the structure of the IF networks performing these functions. We have clarified the existence of seven kinds of IF networks in the cytoplasm of diverse polarized cells: an apex network just under the terminal web, a peripheral network lying just beneath the cell membrane, a granule-associated network surrounding a mass of secretory granules, a Golgi-associated network surrounding the Golgi apparatus, a radial network locating from the perinuclear region to the specific area of the cell membrane, a juxtanuclear network surrounding the nucleus, and an entire cytoplasmic network. In this review, we describe these seven kinds of IF networks and discuss their biological roles.
Collapse
Affiliation(s)
| | - Masumi Suda
- Department of Anatomy, Kawasaki Medical School
| |
Collapse
|
3
|
Iwatsuki H, Suda M. Transient expression of keratin during neuronal development in the adult rabbit spinal ganglion. Anat Sci Int 2009; 85:46-55. [PMID: 19629632 DOI: 10.1007/s12565-009-0054-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2008] [Accepted: 06/19/2009] [Indexed: 12/31/2022]
Abstract
A few neurons of the adult rabbit spinal ganglion express keratin. To examine the characters of these keratin-positive neurons, six kinds of intermediate filament proteins, namely keratin 8, keratin 14, nestin, vimentin, neurofilament 68 (NF-L) and glial fibrillary acidic protein (GFAP), were investigated immunohistochemically in developing and adult rabbit spinal ganglia. At 15 days of gestation, the spinal ganglion increased rapidly in volume and mainly consisted of three kinds of cells: small cells expressing vimentin, spindle-shaped cells co-expressing vimentin and nestin, and ovoid cells with an eccentric nucleus expressing nestin. Since some ovoid cells co-expressed nestin with either NF-L or GFAP, the ovoid cell may be considered to be an embryonic neural stem cell of the ganglion. In addition, a few keratin-positive polymorphic cells could be observed among these three kinds of cells. These polymorphic cells expressed five kinds of intermediate filament proteins, namely keratin 8, keratin 14, nestin, NF-L and GFAP. These cells were also detected in newborn and adult ganglia. A few neurons in the adult ganglion also expressed these five kinds of proteins as a Golgi-associated network. However, neurons expressing these proteins could not be detected in embryonic and newborn ganglia. Therefore, it may be considered that the keratin-positive polymorphic cell is a postnatal neural stem cell of the ganglion and that neurons transiently express keratin when polymorphic cells differentiate into neurons.
Collapse
|