scholarly journals An exceptionally preserved armored dinosaur reveals the morphology and allometry of osteoderms and their horny epidermal coverings

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e4066 ◽  
Author(s):  
Caleb M. Brown
Keyword(s):  
Allometric Scaling ◽  
Soft Tissues ◽  
Organic Residues ◽  
Spine Length ◽  
Relative Contribution ◽  
Specific Morphology ◽  
Allometric Analysis ◽  
Species Specific ◽  
And Function ◽  
Basal Length

Although the evolution and function of “exaggerated” bony projections in ornithischian dinosaurs has been subject to significant debate recently, our understanding of the structure and morphology of their epidermal keratinized coverings is greatly limited. The holotype ofBorealopelta, a new nodosaurid ankylosaur, preserves osteoderms and extensive epidermal structures (dark organic residues), in anatomic position across the entire precaudal length. Contrasting previous specimens, organic epiosteodermal scales, often in the form of horn-like (keratinous) sheaths, cap and exaggerate nearly all osteoderms, allowing for morphometric and allometric analyses of both the bony osteoderms and their horny sheaths. A total of 172 osteoderms were quantified, with osteoderm spine length and height being positively allometric with respect to basal length and width. Despite tight correlations between the different measures amongst all other osteoderms, the large parascapular spines represent consistent outliers. Thickness and relative contribution of the keratinized epiosteodermal scales/sheaths varies greatly by region, ranging from 2% to 6% for posterior thoracics, to ∼25% (1.3×) for the parascapular spines—similar to horn sheaths in some bovid analogues. Relative to the bony cores, the horny portions of the spines are strongly positively allometric (slope = 2.3, CI = 1.8–2.8). Strong allometric scaling, species-specific morphology, and significant keratinous extension of the cervicoscapular spines is consistent with elaboration under socio-sexual selection. This marks the first allometric analysis of ornithischian soft tissues.

scholarly journals Electrical and Ca2+ signaling in dendritic spines of substantia nigra dopaminergic neurons

eLife ◽  
2016 ◽  
Vol 5 ◽  
Author(s):  
Travis A Hage ◽  
Yujie Sun ◽  
Zayd M Khaliq
Keyword(s):  
Dendritic Spines ◽  
Dopaminergic Neurons ◽  
Fluorescence Recovery After Photobleaching ◽  
Dopamine Neurons ◽  
Fixed Tissue ◽  
Spine Length ◽  
Relative Contribution ◽  
Midbrain Dopamine ◽  
Shaft Synapses ◽  
And Function

Little is known about the density and function of dendritic spines on midbrain dopamine neurons, or the relative contribution of spine and shaft synapses to excitability. Using Ca2+ imaging, glutamate uncaging, fluorescence recovery after photobleaching and transgenic mice expressing labeled PSD-95, we comparatively analyzed electrical and Ca2+ signaling in spines and shaft synapses of dopamine neurons. Dendritic spines were present on dopaminergic neurons at low densities in live and fixed tissue. Uncaging-evoked potential amplitudes correlated inversely with spine length but positively with the presence of PSD-95. Spine Ca2+ signals were less sensitive to hyperpolarization than shaft synapses, suggesting amplification of spine head voltages. Lastly, activating spines during pacemaking, we observed an unexpected enhancement of spine Ca2+ midway throughout the spike cycle, likely involving recruitment of NMDA receptors and voltage-gated conductances. These results demonstrate functionality of spines in dopamine neurons and reveal a novel modulation of spine Ca2+ signaling during pacemaking.

scholarly journals Molecular and phenotypic analysis of rodent models reveals conserved and species-specific modulators of human sarcopenia

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Anastasiya Börsch ◽  
Daniel J. Ham ◽  
Nitish Mittal ◽  
Lionel A. Tintignac ◽  
Eugenia Migliavacca ◽  
...  
Keyword(s):  
Muscle Mass ◽  
Inflammatory Responses ◽  
Molecular Data ◽  
Model Organisms ◽  
Sequencing Data ◽  
Phenotypic Analysis ◽  
Age Related ◽  
Analogous Data ◽  
Species Specific ◽  
And Function

AbstractSarcopenia, the age-related loss of skeletal muscle mass and function, affects 5–13% of individuals aged over 60 years. While rodents are widely-used model organisms, which aspects of sarcopenia are recapitulated in different animal models is unknown. Here we generated a time series of phenotypic measurements and RNA sequencing data in mouse gastrocnemius muscle and analyzed them alongside analogous data from rats and humans. We found that rodents recapitulate mitochondrial changes observed in human sarcopenia, while inflammatory responses are conserved at pathway but not gene level. Perturbations in the extracellular matrix are shared by rats, while mice recapitulate changes in RNA processing and autophagy. We inferred transcription regulators of early and late transcriptome changes, which could be targeted therapeutically. Our study demonstrates that phenotypic measurements, such as muscle mass, are better indicators of muscle health than chronological age and should be considered when analyzing aging-related molecular data.

scholarly journals Codon harmonization reduces amino acid misincorporation in bacterially expressed P. falciparum proteins and improves their immunogenicity

AMB Express ◽  
2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Neeraja Punde ◽  
Jennifer Kooken ◽  
Dagmar Leary ◽  
Patricia M. Legler ◽  
Evelina Angov
Keyword(s):  
Protein Structure ◽  
Amino Acid ◽  
Codon Usage ◽  
Dna Sequences ◽  
Structural Integrity ◽  
Host Cells ◽  
Loss Of Function ◽  
Species Specific ◽  
And Function ◽  
The Impact

Abstract Codon usage frequency influences protein structure and function. The frequency with which codons are used potentially impacts primary, secondary and tertiary protein structure. Poor expression, loss of function, insolubility, or truncation can result from species-specific differences in codon usage. “Codon harmonization” more closely aligns native codon usage frequencies with those of the expression host particularly within putative inter-domain segments where slower rates of translation may play a role in protein folding. Heterologous expression of Plasmodium falciparum genes in Escherichia coli has been a challenge due to their AT-rich codon bias and the highly repetitive DNA sequences. Here, codon harmonization was applied to the malarial antigen, CelTOS (Cell-traversal protein for ookinetes and sporozoites). CelTOS is a highly conserved P. falciparum protein involved in cellular traversal through mosquito and vertebrate host cells. It reversibly refolds after thermal denaturation making it a desirable malarial vaccine candidate. Protein expressed in E. coli from a codon harmonized sequence of P. falciparum CelTOS (CH-PfCelTOS) was compared with protein expressed from the native codon sequence (N-PfCelTOS) to assess the impact of codon usage on protein expression levels, solubility, yield, stability, structural integrity, recognition with CelTOS-specific mAbs and immunogenicity in mice. While the translated proteins were expected to be identical, the translated products produced from the codon-harmonized sequence differed in helical content and showed a smaller distribution of polypeptides in mass spectra indicating lower heterogeneity of the codon harmonized version and fewer amino acid misincorporations. Substitutions of hydrophobic-to-hydrophobic amino acid were observed more commonly than any other. CH-PfCelTOS induced significantly higher antibody levels compared with N-PfCelTOS; however, no significant differences in either IFN-γ or IL-4 cellular responses were detected between the two antigens.

scholarly journals WASP confers selective advantage for specific hematopoietic cell populations and serves a unique role in marginal zone B-cell homeostasis and function

Blood ◽  
2008 ◽  
Vol 112 (10) ◽  
pp. 4139-4147 ◽  
Author(s):  
Lisa S. Westerberg ◽  
Miguel A. de la Fuente ◽  
Fredrik Wermeling ◽  
Hans D. Ochs ◽  
Mikael C. I. Karlsson ◽  
...  
Keyword(s):  
T Cells ◽  
B Cells ◽  
B Cell ◽  
Marginal Zone ◽  
Hematopoietic Cells ◽  
Selective Advantage ◽  
Relative Contribution ◽  
B Cell Homeostasis ◽  
And Function

Abstract Development of hematopoietic cells depends on a dynamic actin cytoskeleton. Here we demonstrate that expression of the cytoskeletal regulator WASP, mutated in the Wiskott-Aldrich syndrome, provides selective advantage for the development of naturally occurring regulatory T cells, natural killer T cells, CD4+ and CD8+ T lymphocytes, marginal zone (MZ) B cells, MZ macrophages, and platelets. To define the relative contribution of MZ B cells and MZ macrophages for MZ development, we generated wild-type and WASP-deficient bone marrow chimeric mice, with full restoration of the MZ. However, even in the presence of MZ macrophages, only 10% of MZ B cells were of WASP-deficient origin. We show that WASP-deficient MZ B cells hyperproliferate in vivo and fail to respond to sphingosine-1-phosphate, a crucial chemoattractant for MZ B-cell positioning. Abnormalities of the MZ compartment in WASP−/− mice lead to aberrant uptake of Staphylococcus aureus and to a reduced immune response to TNP-Ficoll. Moreover, WASP-deficient mice have increased levels of “natural” IgM antibodies. Our findings reveal that WASP regulates both development and function of hematopoietic cells. We demonstrate that WASP deficiency leads to an aberrant MZ that may affect responses to blood-borne pathogens and peripheral B-cell tolerance.

scholarly journals Genome-wide markers reveal differentiation between and within the cryptic sister species, sunset and vermilion rockfish

2021 ◽  
Author(s):  
Gary C. Longo ◽  
John Harms ◽  
John R. Hyde ◽  
Matthew T. Craig ◽  
Ana Ramón-Laca ◽  
...  
Keyword(s):  
Management Strategies ◽  
Cost Effective ◽  
Sister Species ◽  
Nucleotide Polymorphisms ◽  
Relative Contribution ◽  
Genetic Groups ◽  
Cost Effective Method ◽  
Species Population ◽  
Single Complex ◽  
Species Specific

AbstractThe vermilion rockfish complex, which consists of the cryptic sister species vermilion and sunset rockfish, is one of the most valuable recreational fisheries on the U.S. West Coast. These species are currently managed as a single complex, and because of uncertainty surrounding the relative contribution of each species within existing data sources, the stock status of each species is not fully known. A reliable and cost-effective method is needed to disentangle these species that will allow for the development of abundance indices, life history profiles, and catch histories that may potentially support species-specific stock assessments. Using restriction-site associated DNA sequence (RADseq) markers we generated 10,003 polymorphic loci to characterize the vermilion rockfish complex. PCA and Bayesian clustering approaches based on these loci clearly distinguished between sunset and vermilion rockfishes and identified hybrid individuals. These loci included 203 highly differentiated (FST ≥ 0.99) single nucleotide polymorphisms, which we consider candidates in the planned development of a diagnostic assay capable of distinguishing between these cryptic species. In addition to clearly delineating to species, subsets of the interspecific markers allowed for insight into intraspecific differentiation in both species. Population genetic analyses for sunset rockfish identified two weakly divergent genetic groups with similar levels of genetic diversity. Vermilion rockfish, however, were characterized by three distinct genetic groups with much stronger signals of differentiation and significantly different genetic diversities. Collectively, these data will contribute to well-informed, species-specific management strategies to protect this valuable species complex.

scholarly journals In Situ Estimation of Carbon Balance of In Vitro Sweetpotato and Tomato Plantlets Cultured with Varying Initial Sucrose Concentrations in the Medium

2002 ◽  
Vol 127 (6) ◽  
pp. 963-970 ◽  
Author(s):  
Chieri Kubota ◽  
Makiko Ezawa ◽  
Toyoki Kozai ◽  
Sandra B. Wilson
Keyword(s):  
Carbon Balance ◽  
Ipomoea Batatas ◽  
Dry Weight ◽  
Photon Flux ◽  
Sugar Uptake ◽  
Relative Contribution ◽  
Carbon Balances ◽  
Species Specific

The effects of initial sucrose (suc) concentrations in the medium (S0) on the carbon balance and growth of sweetpotato [Ipomoea batatas (L.) Lam. `Beniazuma'] and tomato (Lycopersicon esculentum Mill. `HanaQueen') plantlets were studied under controlled environmental conditions. Plantlets were cultured with 0, 7.5, 15, or 30 g·L-1 of S0 under high photosynthetic photon flux (160 to 200 μmol·m-2·s-1) and CO2 enriched (1400 to 2050 μmol·mol-1) conditions. Net photosynthetic rate per leaf area (Pl) decreased and dry weight per plantlet (Wd) increased with increasing S0, but did not differ significantly between S0 of 7.5 to 30 g·L-1 for sweetpotato or 15 to 30 g·L-1 for tomato. Carbon influxes and effluxes of the plantlets by metabolism of medium suc and/or photosynthesis, and respiration were estimated based on measurements of in situ and steady state CO2 exchange rates and sugar uptake during culture. At S0 from 7.5 to 30 g·L-1, photosynthesis was responsible for 82% to 92% and 60% to 67% of carbohydrate assimilation for sweetpotato and tomato, respectively. Estimated carbon balances of plantlets based on the estimated and actual increases of moles of carbon in plant tissue demonstrated that in situ estimation of carbon balance was reasonably accurate for sweetpotato at S0 of 0 to 15 g·L-1 and for tomato at S0 of 0 g·L-1 and that the actual contribution of photosynthesis for tomato at high S0 might be lower than the values estimated in the present experiment. Results showed that initial suc concentration affected the relative contribution of photosynthesis on their carbon balances and that the responses were species specific. The failure of validation at S0 in a range specific to each species suggested the need for further study on carbon metabolism of in vitro plantlets cultured with sugar in the medium.

The skull

2013 ◽  
Author(s):  
Martin E. Atkinson
Keyword(s):  
Soft Tissues ◽  
Clinical Importance ◽  
Dental Students ◽  
Structural Basis ◽  
Facial Skeleton ◽  
Lower Jaw ◽  
Temporomandibular Joints ◽  
Maxilla And Mandible ◽  
And Function ◽  
The Brain

Dental students and practitioners require a sound knowledge of the structure, growth, and development of the skull as a whole. The structure of the skull can be examined and studied more efficiently if you have access to a dried skull or one of the very good plastic replica skulls which are now available; you can identify the structures on the diagrams accompanying the following descriptions and examine a skull at the same time to appreciate the size and relationships of individual components. This chapter outlines the basic principles of the development and structure of the skull and includes some reference to individual bones where this makes understanding easier. The more detailed aspects of particular regions of the skull will be covered in the appropriate chapter describing the whole anatomy of that region; it is much easier to learn the parts of the skull in context of overall structure and function rather than learning a long list of bones, foramina, and muscle attachments in isolation from the related soft tissue structures. Only the maxilla and mandible which are bones of significant clinical importance are described as separate bones. As already demonstrated in Chapter 20, the skull is the structural basis f or the anatomy of the head. The skull has many functions. • It encloses and protects the brain. • It provides protective capsules for the eyes and middle and inner ear. • It forms the skeleton of the entrances to the respiratory and gastrointestinal tracts (GIT) through the nose and mouth, respectively. Those skull components that form the entrance to the GIT also house and support the teeth and soft tissues of the oral region as part of this function. As already outlined in Chapter 20, the skull is made up of several bones joined together to form the cranium which articulates with the separate mandible forming the lower jaw at the temporomandibular joints. The cranium specifically refers to the skull without the mandible; the terms ‘skull’ and ‘cranium’ are not strictly synonymous but they are frequently used as though they are. The cranium can be subdivided into the braincase enclosing the brain and the facial skeleton.

scholarly journals Cortical distal nephron Cl− transport in volume homeostasis and blood pressure regulation

2013 ◽  
Vol 305 (4) ◽  
pp. F427-F438 ◽  
Author(s):  
Susan M. Wall ◽  
Alan M. Weinstein
Keyword(s):  
Blood Pressure ◽  
Pressor Response ◽  
Collecting Duct ◽  
Basolateral Membrane ◽  
Extracellular Volume ◽  
Intercalated Cells ◽  
Cortical Collecting Duct ◽  
Acid Base Balance ◽  
Relative Contribution ◽  
And Function

Renal intercalated cells mediate the secretion or absorption of Cl− and OH−/H+ equivalents in the connecting segment (CNT) and cortical collecting duct (CCD). In so doing, they regulate acid-base balance, vascular volume, and blood pressure. Cl− absorption is either electrogenic and amiloride-sensitive or electroneutral and thiazide-sensitive. However, which Cl− transporter(s) are targeted by these diuretics is debated. While epithelial Na+ channel (ENaC) does not transport Cl−, it modulates Cl− transport probably by generating a lumen-negative voltage, which drives Cl− flux across tight junctions. In addition, recent evidence indicates that ENaC inhibition increases electrogenic Cl− secretion via a type A intercalated cells. During ENaC blockade, Cl− is taken up across the basolateral membrane through the Na+-K+−2Cl− cotransporter (NKCC1) and then secreted across the apical membrane through a conductive pathway (a Cl− channel or an electrogenic exchanger). The mechanism of this apical Cl− secretion is unresolved. In contrast, thiazide diuretics inhibit electroneutral Cl− absorption mediated by a Na+-dependent Cl−/HCO3− exchanger. The relative contribution of the thiazide and the amiloride-sensitive components of Cl− absorption varies between studies and probably depends on the treatment model employed. Cl− absorption increases markedly with angiotensin and aldosterone administration, largely by upregulating the Na+-independent Cl−/HCO3− exchanger pendrin. In the absence of pendrin [ Slc26a4 (−/−) or pendrin null mice], aldosterone-stimulated Cl− absorption is significantly reduced, which attenuates the pressor response to this steroid hormone. Pendrin also modulates aldosterone-induced changes in ENaC abundance and function through a kidney-specific mechanism that does not involve changes in the concentration of a circulating hormone. Instead, pendrin changes ENaC abundance and function, at least in part, by altering luminal HCO3−. This review summarizes mechanisms of Cl− transport in CNT and CCD and how these transporters contribute to the regulation of extracellular volume and blood pressure.

scholarly journals Evolution and function of the hominin forefoot

2018 ◽  
Vol 115 (35) ◽  
pp. 8746-8751 ◽  
Author(s):  
Peter J. Fernández ◽  
Carrie S. Mongle ◽  
Louise Leakey ◽  
Daniel J. Proctor ◽  
Caley M. Orr ◽  
...  
Keyword(s):  
Soft Tissues ◽  
Common Ancestor ◽  
Bipedal Locomotion ◽  
Last Common Ancestor ◽  
Primary Role ◽  
Anthropoid Primates ◽  
And Function ◽  
Metatarsophalangeal Joints ◽  
Selection Of

The primate foot functions as a grasping organ. As such, its bones, soft tissues, and joints evolved to maximize power and stability in a variety of grasping configurations. Humans are the obvious exception to this primate pattern, with feet that evolved to support the unique biomechanical demands of bipedal locomotion. Of key functional importance to bipedalism is the morphology of the joints at the forefoot, known as the metatarsophalangeal joints (MTPJs), but a comprehensive analysis of hominin MTPJ morphology is currently lacking. Here we present the results of a multivariate shape and Bayesian phylogenetic comparative analyses of metatarsals (MTs) from a broad selection of anthropoid primates (including fossil apes and stem catarrhines) and most of the early hominin pedal fossil record, including the oldest hominin for which good pedal remains exist, Ardipithecus ramidus. Results corroborate the importance of specific bony morphologies such as dorsal MT head expansion and “doming” to the evolution of terrestrial bipedalism in hominins. Further, our evolutionary models reveal that the MT1 of Ar. ramidus shifts away from the reconstructed optimum of our last common ancestor with apes, but not necessarily in the direction of modern humans. However, the lateral rays of Ar. ramidus are transformed in a more human-like direction, suggesting that they were the digits first recruited by hominins into the primary role of terrestrial propulsion. This pattern of evolutionary change is seen consistently throughout the evolution of the foot, highlighting the mosaic nature of pedal evolution and the emergence of a derived, modern hallux relatively late in human evolution.

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