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1.
Mol Phylogenet Evol ; 127: 626-637, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29913310

RESUMEN

The relationship between morphology and inheritance is of perennial interest in evolutionary biology and palaeontology. Using three marine snail genera Penion, Antarctoneptunea and Kelletia, we investigate whether systematics based on shell morphology accurately reflect evolutionary lineages indicated by molecular phylogenetics. Members of these gastropod genera have been a taxonomic challenge due to substantial variation in shell morphology, conservative radular and soft tissue morphology, few known ecological differences, and geographical overlap between numerous species. Sampling all sixteen putative taxa identified across the three genera, we infer mitochondrial and nuclear ribosomal DNA phylogenetic relationships within the group, and compare this to variation in adult shell shape and size. Results of phylogenetic analysis indicate that each genus is monophyletic, although the status of some phylogenetically derived and likely more recently evolved taxa within Penion is uncertain. The recently described species P. lineatus is supported by genetic evidence. Morphology, captured using geometric morphometric analysis, distinguishes the genera and matches the molecular phylogeny, although using the same dataset, species and phylogenetic subclades are not identified with high accuracy. Overall, despite abundant variation, we find that shell morphology accurately reflects genus-level classification and the corresponding deep phylogenetic splits identified in this group of marine snails.


Asunto(s)
Exoesqueleto/anatomía & histología , Evolución Molecular , Filogenia , Caracoles/anatomía & histología , Caracoles/genética , Animales , ADN Mitocondrial/genética , ADN Ribosómico/genética , Geografía , Análisis de Secuencia de ADN , Caracoles/clasificación
3.
Plant Cell Environ ; 39(3): 514-26, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26381794

RESUMEN

C4 photosynthesis evolved multiple times in diverse lineages. Most physiological studies comparing C4 plants were not conducted at the low atmospheric CO2 prevailing during their evolution. Here, 24 C4 grasses belonging to three biochemical subtypes [nicotinamide adenine dinucleotide malic enzyme (NAD-ME), phosphoenolpyruvate carboxykinase (PCK) and nicotinamide adenine dinucleotide phosphate malic enzyme (NADP-ME)] and six major evolutionary lineages were grown under ambient (400 µL L(-1) ) and inter-glacial (280 µL L(-1) ) CO2 . We hypothesized that nitrogen-related and water-related physiological traits are associated with subtypes and lineages, respectively. Photosynthetic rate and stomatal conductance were constrained by the shared lineage, while variation in leaf mass per area (LMA), leaf N per area, plant dry mass and plant water use efficiency were influenced by the subtype. Subtype and lineage were equally important for explaining variations in photosynthetic nitrogen use efficiency (PNUE) and photosynthetic water use efficiency (PWUE). CO2 treatment impacted most parameters. Overall, higher LMA and leaf N distinguished the Chloridoideae/NAD-ME group, while NADP-ME and PCK grasses were distinguished by higher PNUE regardless of lineage. Plants were characterized by high photosynthesis and PWUE when grown at ambient CO2 and by high conductance at inter-glacial CO2 . In conclusion, the evolutionary and biochemical diversity among C4 grasses was aligned with discernible leaf physiology, but it remains unknown whether these traits represent ecophysiological adaptation.


Asunto(s)
Dióxido de Carbono/farmacología , Cubierta de Hielo , Nitrógeno/farmacología , Filogenia , Poaceae/fisiología , Agua/fisiología , Modelos Estadísticos , Fotosíntesis/efectos de los fármacos , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/fisiología , Poaceae/efectos de los fármacos , Poaceae/crecimiento & desarrollo
4.
Parasite ; 28: 72, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34698631

RESUMEN

This is the first study assessing the cytoarchitecture of the vitellarium of members of the freshwater, teleost-infecting lineage of blood-flukes (Aporocotylidae). The vitelline cytoarchitecture of two innominate species of Sanguinicola from freshwater fishes in Russia showed that vitelline cells at different stages of maturation are widely distributed throughout much of the body and are mixed with other cell types. The latter feature indicates that use of the term "follicular vitellarium" is inappropriate for species of this genus. An additional characteristic of the vitelline cells in these Sanguinicola spp. is their ability to form long, pseudopodia-like extensions of the peripheral cytoplasm that contact neighbouring vitelline cells and sarcoplasmic extensions, forming both heterologous and homologous intercellular junctions. Within the vitelline duct lumen, the cytoplasm of mature vitelline cells is filled with regular clusters (0.5-1.0 µm in diameter), comprising 10-30 vitelline globules, which have heterogeneous contents and electron-lucent lipid droplets (1.1-1.7 µm in diameter), but no apparent modifications of vitelline globules occur within the vitelline duct. The flattened, ciliated, epithelial lining of the common vitelline duct contains intra-epithelial nuclei, its luminal surface bears shallow lamellae and adjacent cells are adjoined by apical septate junctions. All of these observations, when compared to the marine Aporocotyle simplex, likely represent additional characteristics supporting the divergent evolutionary lineages of marine and freshwater aporocotylids.


TITLE: Cytoarchitecture inhabituelle des « follicules vitellins ¼ chez les digènes infectant le sang des poissons d'eau douce, du genre Sanguinicola (Digenea, Aporocotylidae). ABSTRACT: Il s'agit de la première étude évaluant la cytoarchitecture du vitellarium des membres de la lignée des digènes (Aporocotylidae) infectant le sang des téléostéens d'eau douce. La cytoarchitecture vitelline de deux espèces non nommées de Sanguinicola de poissons d'eau douce de Russie a montré que les cellules vitellines à différents stades de maturation sont largement distribuées dans une grande partie du corps et sont mélangées avec d'autres types cellulaires. Cette dernière caractéristique indique que l'utilisation du terme « vitellarium folliculaire ¼ est inappropriée pour les espèces de ce genre. Une caractéristique supplémentaire des cellules vitellines de ces Sanguinicola spp. est leur capacité à former de longues extensions du cytoplasme périphérique ressemblant à des pseudopodes, qui entrent en contact avec les cellules vitellines voisines et les extensions sarcoplasmiques, formant des jonctions intercellulaires à la fois hétérologues et homologues. Dans la lumière du canal vitellin, le cytoplasme des cellules vitellines mûres est rempli de grappes régulières (0,5 à 1,0 µm de diamètre), comprenant 10 à 30 globules vitellins, qui ont des contenus hétérogènes et des gouttelettes lipidiques (1,1 à 1,7 µm de diamètre) transparentes aux électrons, mais aucune modification apparente des globules vitellines ne se produit dans le canal vitellin. Le revêtement épithélial aplati et cilié du canal vitellin commun contient des noyaux intra-épithéliaux, sa surface luminale porte des lamelles peu profondes et les cellules adjacentes sont jointes par des jonctions septées apicales. Toutes ces observations, comparées à Aporocotyle simplex qui est marin, représentent probablement des caractéristiques supplémentaires soutenant que les lignées évolutives des Aporocotylidae marins et d'eau douce sont divergentes.


Asunto(s)
Trematodos , Animales , Citoplasma , Peces , Agua Dulce , Federación de Rusia
5.
Front Microbiol ; 12: 768868, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35095789

RESUMEN

Cyanobacteria are one of the dominant autotrophs in tropical freshwater communities, yet phages infecting them remain poorly characterized. Here we present the characterization of cyanophage S-SRP02, isolated from a tropical freshwater lake in Singapore, which infects Synechococcus sp. Strain SR-C1 isolated from the same lake. S-SRP02 represents a new evolutionary lineage of cyanophage. Out of 47 open reading frames (ORFs), only 20 ORFs share homology with genes encoding proteins of known function. There is lack of auxiliary metabolic genes which was commonly found as core genes in marine cyanopodoviruses. S-SRP02 also harbors unique structural genes highly divergent from other cultured phages. Phylogenetic analysis and viral proteomic tree further demonstrate the divergence of S-SRP02 from other sequenced phage isolates. Nonetheless, S-SRP02 shares synteny with phage genes of uncultured phages obtained from the Mediterranean Sea deep chlorophyll maximum fosmids, indicating the ecological importance of S-SRP02 and its related viruses. This is further supported by metagenomic mapping of environmental viral metagenomic reads onto the S-SRP02 genome.

6.
PhytoKeys ; 159: 115-126, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32973391

RESUMEN

Rhamnella intermedia, a new evergreen species from southwest Guangxi, is described and illustrated in this study. This species is similar to R. brachycarpa by the size and ratio of length to width of dried fruit and seeds, by which it differs from R. rubrinervis and R. tonkinensis. However, it differs from R. brachycarpa by rarely mucronate seed apices, larger ratio of length to width of leaves, leaf apices acuminate to long acuminate, shorter leaf petioles, and longer fruiting pedicels. Principal component analysis based on phenotypic traits further recognised three separated groups. Rhamnella rubrinervis and R. tonkinensis were clustered into one group; the other two groups represented R. brachycarpa and two Guangxi populations, respectively. Furthermore, phylogenetic analysis of nuclear ITS sequence variations highly supported that the two Guangxi populations represented an independent evolutionary lineage and were closest to R. rubrinervis. Four fixed nucleotide sites were found and were different from R. rubrinervis. However, besides the differentiated traits in seeds and fruit, densely pilose young branches also separated them from R. rubrinervis. In addition, during our field investigations, none of the three closely related species were found at locations where this new species was distributed. Therefore, this new species, based on the two Guangxi populations, is named R. intermedia. The key to four closely related species is also presented.

7.
Protein Pept Lett ; 24(11): 996-1007, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28799506

RESUMEN

BACKGROUND: Study of folded structure of proteins provides insights into their biological functions, conformational dynamics and molecular evolution. Current methods of elucidating folded structure of proteins are laborious, low-throughput, and constrained by various limitations. Arising from these methods is the need for a sensitive, quantitative, rapid and high-throughput method not only analysing the folded structure of proteins, but also to monitor dynamic changes under physiological or experimental conditions. OBJECTIVES: In this focused review, we outline the foundation and limitations of current protein structure-determination methods prior to discussing the advantages of an emerging antibody epitope analysis for applications in structural, conformational and evolutionary studies of proteins. METHODS: We discuss the application of this method using representative examples in monitoring allosteric conformation of regulatory proteins and the determination of the evolutionary lineage of related proteins and protein isoforms. RESULTS: The versatility of the method described herein is validated by the ability to modulate a variety of assay parameters to meet the needs of the user in order to monitor protein conformation. Furthermore, the assay has been used to clarify the lineage of troponin isoforms beyond what has been depicted by sequence homology alone, demonstrating the nonlinear evolutionary relationship between primary structure and tertiary structure of proteins. CONCLUSION: The antibody epitope analysis method is a highly adaptable technique of protein conformation elucidation, which can be easily applied without the need for specialized equipment or technical expertise. When applied in a systematic and strategic manner, this method has the potential to reveal novel and biomedically meaningful information for structure-function relationship and evolutionary lineage of proteins.


Asunto(s)
Anticuerpos/análisis , Anticuerpos/química , Epítopos/análisis , Epítopos/química , Sitio Alostérico , Secuencia de Aminoácidos , Evolución Molecular , Conformación Proteica , Isoformas de Proteínas/química
8.
Front Psychiatry ; 6: 130, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26441691

RESUMEN

Vasopressin (VP) and VP-like neuropeptides are evolutionarily stable peptides found in all vertebrate species. In non-mammalian vertebrates, vasotocin (VT) plays a role similar to mammalian VP, whereas mesotocin and isotocin are functionally similar to mammalian oxytocin (OT). Here, we review the involvement of VP in brain circuits, synaptic plasticity, evolution, and function, highlighting the role of VP in social behavior. In all studied species, VP is encoded on chromosome 20p13, and in mammals, VP is produced in specific hypothalamic nuclei and released by the posterior pituitary. The role of VP is mediated by the stimulation of the V1a, V1b, and V2 receptors as well as the oxytocinergic and purinergic receptors. VT and VP functions are usually related to osmotic and cardiovascular homeostasis when acting peripherally. However, these neuropeptides are also critically involved in the central modulation of social behavior displays, such as pairing recognition, pair-bonding, social memory, sexual behavior, parental care, and maternal and aggressive behavior. Evidence suggests that these effects are primarily mediated by V1a receptor in specific brain circuits that provide important information for the onset and control of social behaviors in normal and pathological conditions.

9.
Int J Parasitol ; 45(6): 409-17, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25770861

RESUMEN

Hosts and parasites are in a perpetual co-evolutionary "arms race". Due to their short generation time and large reproductive output, parasites are commonly believed to be ahead in this race, although increasing evidence exists that parasites are not always ahead in the arms race - in part owing to evolutionary lineage and recent ecological history. We assess local adaptation of hosts and parasites, and determine whether adaptation was influenced by ecological or evolutionary history, using full reciprocal cross-infections of four Gyrodactylus ectoparasite populations and their four guppy (Poecilia reticulata) host populations in Trinidad. To consider effects of evolutionary lineage and recent ecology, these four populations were collected from two different river drainages (Marianne and Aripo) and two different predation environments (high and low). The highest infection levels were obtained when parasites from the Aripo lineage infected guppies from the Marianne lineage, indicating a higher infectivity, virulence and/or reproductive success of the Aripo parasites. Aripo lineage guppies were also better able to limit Gyrodactylus population growth than guppies from the Marianne River, indicating their strong "resistance" to Gyrodactylus regardless of the source of the parasite. Predation environment had no detectable influence on host-parasite population dynamics of sympatric or allopatric combinations. The much stronger effect of evolutionary lineage (i.e., river) than recent ecological history (i.e., predation) emphasises its importance in driving co-evolutionary dynamics, and should be explored further in future studies on local host-parasite adaptation.


Asunto(s)
Infestaciones Ectoparasitarias/veterinaria , Enfermedades de los Peces/parasitología , Poecilia/parasitología , Adaptación Fisiológica , Animales , Evolución Biológica , Ecosistema , Infestaciones Ectoparasitarias/epidemiología , Infestaciones Ectoparasitarias/parasitología , Enfermedades de los Peces/epidemiología , Predisposición Genética a la Enfermedad , Ríos , Trinidad y Tobago
10.
Stud Hist Philos Biol Biomed Sci ; 44(3): 262-71, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23684745

RESUMEN

Races may exist in humans in a cultural sense, but biological concepts of race are needed to access their reality in a non-species-specific manner and to see if cultural categories correspond to biological categories within humans. Modern biological concepts of race can be implemented objectively with molecular genetic data through hypothesis-testing. Genetic data sets are used to see if biological races exist in humans and in our closest evolutionary relative, the chimpanzee. Using the two most commonly used biological concepts of race, chimpanzees are indeed subdivided into races but humans are not. Adaptive traits, such as skin color, have frequently been used to define races in humans, but such adaptive traits reflect the underlying environmental factor to which they are adaptive and not overall genetic differentiation, and different adaptive traits define discordant groups. There are no objective criteria for choosing one adaptive trait over another to define race. As a consequence, adaptive traits do not define races in humans. Much of the recent scientific literature on human evolution portrays human populations as separate branches on an evolutionary tree. A tree-like structure among humans has been falsified whenever tested, so this practice is scientifically indefensible. It is also socially irresponsible as these pictorial representations of human evolution have more impact on the general public than nuanced phrases in the text of a scientific paper. Humans have much genetic diversity, but the vast majority of this diversity reflects individual uniqueness and not race.


Asunto(s)
Evolución Biológica , Variación Genética , Pan troglodytes/genética , Grupos Raciales/genética , Adaptación Fisiológica , África , Animales , Humanos
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