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Warren G. Bryson - One of the best experts on this subject based on the ideXlab platform.
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Arrangement of trichokeratin intermediate filaments and matrix in the cortex of Merino wool.
Journal of structural biology, 2010Co-Authors: Duane P. Harland, Jonathan P. Caldwell, Joy L. Woods, Richard J. Walls, Warren G. BrysonAbstract:Tomograms of transverse sections of Merino wool fibers obtained from fleeces differing in fiber curvature were reconstructed from image series collected using a 300kV transmission electron microscope. Trichokeratin intermediate filaments (IFs) from the ortho-, para- and mesocortices were modeled from the tomograms. IFs were predominantly arranged in left-handed concentric helices with the relative angle of IFs increasing progressively from the center to the periphery of Orthocortex macrofibrils. The median increase in IF angle between adjacent IFs between the center and periphery was 2.5°. The length of one turn of the helical path of an IF was calculated to be approximately 1μm for an IF tilted at 30° and positioned 100nm from the macrofibril center. With the exception of one paracortex macrofibril that weakly resembled an Orthocortex macrofibril, all para- and mesocortex macrofibrils modeled had a parallel arrangement of the IFs, with a more ordered arrangement found in the mesocortex. Within the limited sample set, there appeared to be no significant relationship between IF angle and fiber curvature. We examined the matrix/IF ratio (in the form of proportion of matrix to one IF, calculated from IF center-to-center distance and IF diameter) for 28 macrofibrils used for modeling. The proportion of matrix was significantly different in the different cortex cell types, with paracortex having the most (0.61), Orthocortex having the least (0.42), and mesocortex being intermediate (0.54). Fibers of different crimp type (high, medium or low crimp) were not significantly different from each other with respect to matrix proportion.
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Protein expression in orthocortical and paracortical cells of merino wool fibers.
Journal of agricultural and food chemistry, 2009Co-Authors: Jeffrey E. Plowman, Santanu Deb-choudhury, Warren G. Bryson, Stefan Clerens, Jolon M. DyerAbstract:Crimp and bulk, important wool fiber properties, are thought to be related to differences in the protein composition of the Orthocortex and paracortex. Fiber morphological studies have demonstrated that the paracortex has a higher proportion of matrix and cysteine than the Orthocortex. While there is some evidence for the differential expression of genes between these cell types in the follicle, this has not been demonstrated satisfactorily in the mature fiber. Using proteolytic digestion of wool fibers, followed by ultrasonic disruption to obtain relatively pure fractions of both cell types, the KAP3 high sulfur protein family was found to be present in higher concentrations in the paracortex. This significant finding provides an explanation for the higher cysteine content reported in the paracortex. This represents an advance in our understanding of protein expression variation in the Orthocortex and paracortex, and how this relates to key physical and mechanical properties of wool fibers.
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The differential expression of proteins in the cortical cells of wool and hair fibres.
Experimental dermatology, 2007Co-Authors: Jeffrey E. Plowman, Louise N. Paton, Warren G. BrysonAbstract:Three different cell types have been identified in the cortex of wool: Orthocortex, mesocortex and paracortex. Fine wool fibres, particularly Merino sheep, are noted for their bilateral distribution of orthocortical and paracortical cells, with the latter following the concave side of the crimp wave. Furthermore, studies have indicated that the paracortex has a higher concentration of cysteine than the Orthocortex. This has been supported by in situ hybridization studies in the follicle that have shown that sulphur-rich proteins are initially expressed on the paracortical side of the fibre, with some becoming more uniformly spread, laterally, over the entire fibre as the keratinization process progresses. In contrast, proteins high in glycine and tyrosine tend to be expressed initially on the orthocortical side of the follicle. While these in vitro studies have pointed to where specific proteins are located in the follicle, elucidating the situation for the mature fibre has been less easy. A range of approaches have been used to separate orthocortical and paracortical cells and these have only been able to provide evidence for a higher level of cysteine in the latter. Electrophoretic studies have found a number of differences in protein expression between the two sides but have not specifically identified which proteins. Thus, there appears to be good evidence for the paracortex containing a higher proportion of proteins in the ultra-high sulphur class but there is some uncertainty regarding the exact distribution of proteins high in glycine and tyrosine.
Yoshiyuki Amemiya - One of the best experts on this subject based on the ideXlab platform.
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Structural analysis of single wool fibre by scanning microbeam SAXS
Journal of Applied Crystallography, 2005Co-Authors: Yoshio Kajiura, Shunichi Watanabe, Takashi Itou, Atsuo Iida, Yuya Shinohara, Yoshiyuki AmemiyaAbstract:The technique of scanning microbeam small-angle X-ray scattering (SAXS) has been applied to investigate the inhomogeneity in the nanostructure of a single bilateral wool fibre in relation to two types of cortices, the so-called Orthocortex and paracortex, which are located at the outer side and the inner side of the curved fibre, respectively. On the basis of the equatorial scattering intensity profiles from both experiments and simulation, the inhomogeneity in the mean IF (intermediate filament)-IF distance, IF diameter and IF orientation, corresponding to the structural difference between the Orthocortex and the paracortex in bilateral wool fibre, has been quantitatively obtained.
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Structural Analysis of a Single Keratin Fiber by Scanning Microbeam SAXS
2003Co-Authors: Yoshio Kajiura, Takashi Itou, Yoshiyuki AmemiyaAbstract:Introduction The nano structure of a single wool fiber has been studied by scanning microbeam SAXS to reveal the relationship between the lateral heterogeneity of keratin structure and the curl shape of a fiber. A Merino wool fiber is about 10~50μm in diameter and has a strong curl shape. It is mainly composed of cuticle and cortex. The cortex constitutes the major part of the fiber mass and consists mainly of the crystalline α-keratin filaments (Intermediate Filaments:IFs) embedded in the amorphous matrix protein (Keratin Associated Protein:KAP). Most wool fibers contain two (sometimes three) types of cortical cells, so called Orthocortex and paracortex (and mesocortex), and the bilateral arrangement of them (usually Orthocortex and paracortex) is associated with the crimped structure of wool fibers [1]. It has been found that the orthocortical cells tend to be located at the outer side of the fiber curve and also there are obvious differences of the geometrical arrangement of the IFs among these cortical cells. TEM observation of wool’s cross sections shows that the IFs within the paracortical cells are almost parallel each other along the fiber direction, whereas those within the orthocortical cells are supposed to be twisted. The purpose of our study is to analyze the inhomogeneity in IF microstructure of a single bilateral wool fiber in intact condition by measuring SAXS patterns with an X-ray microbeam scanning along the lateral direction of the fiber.
Duane P. Harland - One of the best experts on this subject based on the ideXlab platform.
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The wool proteome and fibre characteristics of three distinct genetic ovine breeds from Portugal
Journal of proteomics, 2020Co-Authors: Jeffrey E. Plowman, Duane P. Harland, Ancy Thomas, James A. Vernon, Stefan Clerens, Alexandre Campos, Severiano Rocha E Silva, Chikako Van Koten, Charles A. Hefer, André M. AlmeidaAbstract:Abstract Wool properties and commodity value vary considerably between breeds. In Portugal, three major ovine groups exist: Churros, Bordaleiros and Merinos. This work studies the effect of the ovine genotype on the wool proteome of such groups. Wool was collected from 15 ewes/breed and genetic groups: Churra da Terra Quente (CTQ) or Churro, Serra da Estrela (SE) or Bordaleiro and Merino Branco (MB) or Merino. Proteins were extracted and subjected to label-free proteomics analysis. A total of 50 keratinous protein groups were identified in all the samples, divided into type I and II keratins and the keratin associated proteins: high-glycine-tyrosine proteins, ultra-high sulphur proteins and high-sulphur proteins. Major differences were found between MB and CTQ with respect to K75 and K38, both medullar proteins and to a lesser extent between SE and CTQ suggesting that these might be good markers for this trait in wool. Partial least squares discriminatory analysis proved MB to be readily distinguishable from the other two breeds. Further differences were noted in keratin associated protein levels between the three breeds, normally an indicator of higher levels of Orthocortex and also their relationship to high curvature, high crimp fibres like Merino. Biological significance The ovine genetic type has strong effects on wool productivity parameters and quality traits. In this work, we compare the proteomes and the microscopical characteristics of the wool from three distinct ovine genetic types from Portugal: Merino, Bordaleiro and Churro. Important differences were found regarding keratin associated proteins and keratins K75 and K38, suggested as putative markers for quality traits in the wool proteome such as the average curvature.
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Differences between ultrastructure and protein composition in straight hair fibres.
Zoology (Jena Germany), 2019Co-Authors: Jeffrey E. Plowman, Duane P. Harland, D. R. Scobie, Denis O’connell, Ancy Thomas, Peter Brorens, Marina Richena, Esther D. Meenken, Amy J. Phillips, James A. VernonAbstract:Abstract Mammalian hairs are internally patterned from both a morphological and proteomic perspective to exhibit specific functional traits, including curvature, which is important for coat structure affecting thermo-insulation. Most functional traits in mammalian coats are complex emergent phenomena associated with single-fibre properties that are themselves multi-variate and poorly understood. Here we compare hair curvature, ultrastructure, microstructure, protein composition and felting (a functional attribute) between fibres from natural straight-wool mutants of domestic sheep (felting lustre-mutant sheep), their wild-type relatives and also with a straight-haired semi-lustrous breed, English Leicester. Proteomic and structural results confirmed that the straight lustre mutant fibres had a normal cuticle and the same cortical protein and ultrastructural building blocks as wild-type fibres, but differed from equivalent fibres from wild-type relatives and English Leicester in layout and relative proportions. While curved wild-type fibres had bilaterally arranged Orthocortex and paracortex, and English Leicester fibres had a scatter of paracortex on a background of Orthocortex, lustre mutant fibres typically had a complete or partial ring of Orthocortex surrounding a paracortex core, and sometimes a central Orthocortex (similar to straight human and goat hairs). Lustre mutant fibres also had a reduced abundance of some high glycine-tyrosine proteins, normally associated with the Orthocortex, with a possible relationship between the protein expression of the KAP8 and KAP16 protein families and fibre felting properties. We conclude that through control of the internal fibre patterning, multiple-solutions to hair curvature are possible, and variation may affect mechanical phenotype differently. Felting lustre mutant sheep will be a useful tool for discriminating cause and effect from non-causative correlation in mammalian fibre development.
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Three-dimensional architecture of macrofibrils in the human scalp hair cortex.
Journal of structural biology, 2014Co-Authors: Duane P. Harland, James A. Vernon, Jolon M. Dyer, Joy L. Woods, Richard J. Walls, Fraser I. BellAbstract:Human scalp hairs are comprised of a central cortex enveloped by plate-like cuticle cells. The elongate cortex cells of mature fibres are composed primarily of macrofibrils-bundles of hard-keratin intermediate filaments (IFs) chemically cross-linked within a globular protein matrix. In wool, three cell types (ortho-, meso- and paracortex) contain macrofibrils with distinctly different filament arrangements and matrix fractions, but in human hair macrofibril-cell type relationships are less clear. Here we show that hair macrofibrils all have a similar matrix fraction (∼0.4) and are typically composed of a double-twist architecture in which a central IF is surrounded by concentric rings of tangentially-angled IFs. The defining parameter is the incremental angle increase (IF-increment) between IFs of successive rings. Unlike the wool Orthocortex, hair double-twist macrofibrils have considerable inter-macrofibril variation in IF increment (0.05-0.35°/nm), and macrofibril size and IF increment are negatively correlated. Correspondingly, angular difference between central and outer-most IFs is up to 40° in small macrofibrils, but only 5-10° in large macrofibrils. Single cells were observed containing mixtures of macrofibrils with different diameters. These new observations advance our understanding of the nano-level and cell-level organisation of human hair, with implications for interpretation of structure with respect the potential roles of cortex cell types in defining the mechanical properties of hair.
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morphology and ultrastructure of antler velvet hair and body hair from red deer cervus elaphus
Journal of Morphology, 2011Co-Authors: Joy L. Woods, Duane P. Harland, James A Verno, Gail L Krsinic, Richard J. WallsAbstract:We provide a detailed description of the ultrastructure of deer hair fibers. Guard hairs and underhairs from the winter coat of red deer (Cervus elaphus), and antler velvet hairs from the same species were examined. All fibers displayed the typical keratin fiber morphology of overlapping cuticle cells surrounding a core of cortex cells, and often a centrally-located medulla, but there were considerable differences in the diameter, cuticle thickness, and scale pattern, and in the relative amounts of cortex and medulla along individual fibers, and between the different types of fiber. In addition, closer examination of cortex cells using transmission electron microscopy revealed considerable differences in the arrangement of intermediate filaments in the different fiber types. Fine underhairs appeared similar to fine wool fibers from sheep because intermediate filament arrangements were very similar to those found in wool Orthocortex cells and paracortex cells. In addition, a similar bilateral distribution of these cell types was evident. However, in the antler velvet hairs and the guard hairs, intermediate filament arrangements were more variable and complex, and showed similarities to those in heterotype cortex cells described for human hair. J. Morphol., 2011. © 2010 Wiley-Liss, Inc.
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Arrangement of trichokeratin intermediate filaments and matrix in the cortex of Merino wool.
Journal of structural biology, 2010Co-Authors: Duane P. Harland, Jonathan P. Caldwell, Joy L. Woods, Richard J. Walls, Warren G. BrysonAbstract:Tomograms of transverse sections of Merino wool fibers obtained from fleeces differing in fiber curvature were reconstructed from image series collected using a 300kV transmission electron microscope. Trichokeratin intermediate filaments (IFs) from the ortho-, para- and mesocortices were modeled from the tomograms. IFs were predominantly arranged in left-handed concentric helices with the relative angle of IFs increasing progressively from the center to the periphery of Orthocortex macrofibrils. The median increase in IF angle between adjacent IFs between the center and periphery was 2.5°. The length of one turn of the helical path of an IF was calculated to be approximately 1μm for an IF tilted at 30° and positioned 100nm from the macrofibril center. With the exception of one paracortex macrofibril that weakly resembled an Orthocortex macrofibril, all para- and mesocortex macrofibrils modeled had a parallel arrangement of the IFs, with a more ordered arrangement found in the mesocortex. Within the limited sample set, there appeared to be no significant relationship between IF angle and fiber curvature. We examined the matrix/IF ratio (in the form of proportion of matrix to one IF, calculated from IF center-to-center distance and IF diameter) for 28 macrofibrils used for modeling. The proportion of matrix was significantly different in the different cortex cell types, with paracortex having the most (0.61), Orthocortex having the least (0.42), and mesocortex being intermediate (0.54). Fibers of different crimp type (high, medium or low crimp) were not significantly different from each other with respect to matrix proportion.
Jeffrey E. Plowman - One of the best experts on this subject based on the ideXlab platform.
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The wool proteome and fibre characteristics of three distinct genetic ovine breeds from Portugal
Journal of proteomics, 2020Co-Authors: Jeffrey E. Plowman, Duane P. Harland, Ancy Thomas, James A. Vernon, Stefan Clerens, Alexandre Campos, Severiano Rocha E Silva, Chikako Van Koten, Charles A. Hefer, André M. AlmeidaAbstract:Abstract Wool properties and commodity value vary considerably between breeds. In Portugal, three major ovine groups exist: Churros, Bordaleiros and Merinos. This work studies the effect of the ovine genotype on the wool proteome of such groups. Wool was collected from 15 ewes/breed and genetic groups: Churra da Terra Quente (CTQ) or Churro, Serra da Estrela (SE) or Bordaleiro and Merino Branco (MB) or Merino. Proteins were extracted and subjected to label-free proteomics analysis. A total of 50 keratinous protein groups were identified in all the samples, divided into type I and II keratins and the keratin associated proteins: high-glycine-tyrosine proteins, ultra-high sulphur proteins and high-sulphur proteins. Major differences were found between MB and CTQ with respect to K75 and K38, both medullar proteins and to a lesser extent between SE and CTQ suggesting that these might be good markers for this trait in wool. Partial least squares discriminatory analysis proved MB to be readily distinguishable from the other two breeds. Further differences were noted in keratin associated protein levels between the three breeds, normally an indicator of higher levels of Orthocortex and also their relationship to high curvature, high crimp fibres like Merino. Biological significance The ovine genetic type has strong effects on wool productivity parameters and quality traits. In this work, we compare the proteomes and the microscopical characteristics of the wool from three distinct ovine genetic types from Portugal: Merino, Bordaleiro and Churro. Important differences were found regarding keratin associated proteins and keratins K75 and K38, suggested as putative markers for quality traits in the wool proteome such as the average curvature.
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Differences between ultrastructure and protein composition in straight hair fibres.
Zoology (Jena Germany), 2019Co-Authors: Jeffrey E. Plowman, Duane P. Harland, D. R. Scobie, Denis O’connell, Ancy Thomas, Peter Brorens, Marina Richena, Esther D. Meenken, Amy J. Phillips, James A. VernonAbstract:Abstract Mammalian hairs are internally patterned from both a morphological and proteomic perspective to exhibit specific functional traits, including curvature, which is important for coat structure affecting thermo-insulation. Most functional traits in mammalian coats are complex emergent phenomena associated with single-fibre properties that are themselves multi-variate and poorly understood. Here we compare hair curvature, ultrastructure, microstructure, protein composition and felting (a functional attribute) between fibres from natural straight-wool mutants of domestic sheep (felting lustre-mutant sheep), their wild-type relatives and also with a straight-haired semi-lustrous breed, English Leicester. Proteomic and structural results confirmed that the straight lustre mutant fibres had a normal cuticle and the same cortical protein and ultrastructural building blocks as wild-type fibres, but differed from equivalent fibres from wild-type relatives and English Leicester in layout and relative proportions. While curved wild-type fibres had bilaterally arranged Orthocortex and paracortex, and English Leicester fibres had a scatter of paracortex on a background of Orthocortex, lustre mutant fibres typically had a complete or partial ring of Orthocortex surrounding a paracortex core, and sometimes a central Orthocortex (similar to straight human and goat hairs). Lustre mutant fibres also had a reduced abundance of some high glycine-tyrosine proteins, normally associated with the Orthocortex, with a possible relationship between the protein expression of the KAP8 and KAP16 protein families and fibre felting properties. We conclude that through control of the internal fibre patterning, multiple-solutions to hair curvature are possible, and variation may affect mechanical phenotype differently. Felting lustre mutant sheep will be a useful tool for discriminating cause and effect from non-causative correlation in mammalian fibre development.
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Protein expression in orthocortical and paracortical cells of merino wool fibers.
Journal of agricultural and food chemistry, 2009Co-Authors: Jeffrey E. Plowman, Santanu Deb-choudhury, Warren G. Bryson, Stefan Clerens, Jolon M. DyerAbstract:Crimp and bulk, important wool fiber properties, are thought to be related to differences in the protein composition of the Orthocortex and paracortex. Fiber morphological studies have demonstrated that the paracortex has a higher proportion of matrix and cysteine than the Orthocortex. While there is some evidence for the differential expression of genes between these cell types in the follicle, this has not been demonstrated satisfactorily in the mature fiber. Using proteolytic digestion of wool fibers, followed by ultrasonic disruption to obtain relatively pure fractions of both cell types, the KAP3 high sulfur protein family was found to be present in higher concentrations in the paracortex. This significant finding provides an explanation for the higher cysteine content reported in the paracortex. This represents an advance in our understanding of protein expression variation in the Orthocortex and paracortex, and how this relates to key physical and mechanical properties of wool fibers.
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The differential expression of proteins in the cortical cells of wool and hair fibres.
Experimental dermatology, 2007Co-Authors: Jeffrey E. Plowman, Louise N. Paton, Warren G. BrysonAbstract:Three different cell types have been identified in the cortex of wool: Orthocortex, mesocortex and paracortex. Fine wool fibres, particularly Merino sheep, are noted for their bilateral distribution of orthocortical and paracortical cells, with the latter following the concave side of the crimp wave. Furthermore, studies have indicated that the paracortex has a higher concentration of cysteine than the Orthocortex. This has been supported by in situ hybridization studies in the follicle that have shown that sulphur-rich proteins are initially expressed on the paracortical side of the fibre, with some becoming more uniformly spread, laterally, over the entire fibre as the keratinization process progresses. In contrast, proteins high in glycine and tyrosine tend to be expressed initially on the orthocortical side of the follicle. While these in vitro studies have pointed to where specific proteins are located in the follicle, elucidating the situation for the mature fibre has been less easy. A range of approaches have been used to separate orthocortical and paracortical cells and these have only been able to provide evidence for a higher level of cysteine in the latter. Electrophoretic studies have found a number of differences in protein expression between the two sides but have not specifically identified which proteins. Thus, there appears to be good evidence for the paracortex containing a higher proportion of proteins in the ultra-high sulphur class but there is some uncertainty regarding the exact distribution of proteins high in glycine and tyrosine.
Yoshio Kajiura - One of the best experts on this subject based on the ideXlab platform.
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Structural analysis of single wool fibre by scanning microbeam SAXS
Journal of Applied Crystallography, 2005Co-Authors: Yoshio Kajiura, Shunichi Watanabe, Takashi Itou, Atsuo Iida, Yuya Shinohara, Yoshiyuki AmemiyaAbstract:The technique of scanning microbeam small-angle X-ray scattering (SAXS) has been applied to investigate the inhomogeneity in the nanostructure of a single bilateral wool fibre in relation to two types of cortices, the so-called Orthocortex and paracortex, which are located at the outer side and the inner side of the curved fibre, respectively. On the basis of the equatorial scattering intensity profiles from both experiments and simulation, the inhomogeneity in the mean IF (intermediate filament)-IF distance, IF diameter and IF orientation, corresponding to the structural difference between the Orthocortex and the paracortex in bilateral wool fibre, has been quantitatively obtained.
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Structural Analysis of a Single Keratin Fiber by Scanning Microbeam SAXS
2003Co-Authors: Yoshio Kajiura, Takashi Itou, Yoshiyuki AmemiyaAbstract:Introduction The nano structure of a single wool fiber has been studied by scanning microbeam SAXS to reveal the relationship between the lateral heterogeneity of keratin structure and the curl shape of a fiber. A Merino wool fiber is about 10~50μm in diameter and has a strong curl shape. It is mainly composed of cuticle and cortex. The cortex constitutes the major part of the fiber mass and consists mainly of the crystalline α-keratin filaments (Intermediate Filaments:IFs) embedded in the amorphous matrix protein (Keratin Associated Protein:KAP). Most wool fibers contain two (sometimes three) types of cortical cells, so called Orthocortex and paracortex (and mesocortex), and the bilateral arrangement of them (usually Orthocortex and paracortex) is associated with the crimped structure of wool fibers [1]. It has been found that the orthocortical cells tend to be located at the outer side of the fiber curve and also there are obvious differences of the geometrical arrangement of the IFs among these cortical cells. TEM observation of wool’s cross sections shows that the IFs within the paracortical cells are almost parallel each other along the fiber direction, whereas those within the orthocortical cells are supposed to be twisted. The purpose of our study is to analyze the inhomogeneity in IF microstructure of a single bilateral wool fiber in intact condition by measuring SAXS patterns with an X-ray microbeam scanning along the lateral direction of the fiber.