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1.
Development ; 150(17)2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37519269

RESUMEN

Changes in gene expression represent an important source of phenotypic innovation. Yet how such changes emerge and impact the evolution of traits remains elusive. Here, we explore the molecular mechanisms associated with the development of masculinizing ovotestes in female moles. By performing integrative analyses of epigenetic and transcriptional data in mole and mouse, we identified the co-option of SALL1 expression in mole ovotestes formation. Chromosome conformation capture analyses highlight a striking conservation of the 3D organization at the SALL1 locus, but an evolutionary divergence of enhancer activity. Interspecies reporter assays support the capability of mole-specific enhancers to activate transcription in urogenital tissues. Through overexpression experiments in transgenic mice, we further demonstrate the capability of SALL1 to induce kidney-related gene programs, which are a signature of mole ovotestes. Our results highlight the co-option of gene expression, through changes in enhancer activity, as a plausible mechanism for the evolution of traits.


Asunto(s)
Riñón , Topos , Animales , Femenino , Ratones , Riñón/metabolismo , Ratones Transgénicos , Topos/genética
2.
Pediatr Dermatol ; 41(2): 318-319, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38494778

RESUMEN

Congenital melanocytic nevi (CMN) are special types of moles. CMN happen when extra pigment-making cells (melanocytes) grow in a baby's skin while the baby is forming before birth. They are not caused by anything their parent did or didn't do during pregnancy. These moles are there when the baby is born, stay on the skin for life, and grow as the child grows.


Asunto(s)
Topos , Nevo Pigmentado , Neoplasias Cutáneas , Lactante , Niño , Humanos , Animales , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/congénito , Melanocitos , Nevo Pigmentado/diagnóstico , Nevo Pigmentado/congénito , Piel
3.
J Anat ; 242(2): 257-276, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36156797

RESUMEN

The forelimb is involved in many behaviours including locomotion. Notably, the humero-ulnar articulation, implicated in the elbow joint, is of particular importance for both mobility and stability. Functional constraints, induced in part by environmental plasticity, are thought to drive an important part of the bone shape as bone directly responds and remodels in response to both muscle and external forces. In this context, the study of subterranean moles is of particular interest. These moles occupy a hard and heavy medium in comparison with air or water, requiring a powerful body structure to shear and shift the soil. Their general morphology is therefore adapted to digging and to their subterranean lifestyle. The various morpho-functional patterns, which drive diverse abilities according to the environment, are likely targets of natural selection and it is, therefore, useful to understand the relationships between the bone shape and their function. Here, we quantify, through 3D geometric morphometric methods, the interspecific variability in the morphology of the ulna and humerus of three Talpa species, including the new species Talpa aquitania, to infer their potential consequence in species digging performance. We also quantify shape covariation and morphological integration between the humerus and the ulna to test whether these bones evolve as a uniform functional unit or as more or less independent modules. Our results show that interspecific anatomical differences in the humerus and ulna exist among the three species. Shape changes are mostly located at the level of joints and muscle attachments. As the species tend to live in allopatry and the fossorial lifestyle induces strong ecological constraints, interspecific variations could be explained by the properties of the environment in which they live, such as the compactness of the soil. Our results also show that the humerus and ulna are highly integrated. The covariation between the humerus and ulna in moles is dominated by variation in the attachment areas and particularly of the attachment areas of shoulder muscles concerning the humerus, which affect the mechanical force deployed during locomotion and digging. This study also highlights that in the new species, T. aquitania, variations in anatomical structure (general shape and joints) exist and are related to the locality of collect of the individuals.


Asunto(s)
Topos , Humanos , Animales , Topos/anatomía & histología , Topos/fisiología , Húmero/anatomía & histología , Cúbito , Extremidad Superior , Suelo
4.
J Exp Biol ; 226(3)2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36688286

RESUMEN

The star-nosed mole (Condylura cristata) is renowned for its densely innervated 22 appendage star-like rostrum ('star') specialized for tactile sensation. As a northerly distributed insectivorous mammal exploiting aquatic and terrestrial habitats, these vascularized nasal rays are regularly exposed to cold water and thermally conductive soil, leading us to ask whether the star surface temperature, a proxy for blood flow, conforms to the local ambient temperature to conserve body heat. Alternatively, given the exquisite sensory nature of the star, we posited that the uninsulated rays may be kept warm when foraging to maintain high mechanosensory function. To test these hypotheses, we remotely monitored surface temperatures in wild-caught star-nosed moles. Although the tail acted as a thermal window exhibiting clear vasoconstriction/vasodilation, the star varied passively in surface temperature, with little evidence for thermoregulatory vasomotion. This thermoconforming response may have evolved to minimize conductive heat loss to the water or wet soils when foraging.


Asunto(s)
Topos , Animales , Topos/fisiología , Eulipotyphla , Nariz , Tacto/fisiología , Regulación de la Temperatura Corporal/fisiología , Suelo
5.
Int J Mol Sci ; 24(11)2023 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-37298606

RESUMEN

The general notion of complete hydatidiform moles is that most of them consist entirely of paternal DNA; hence, they do not express p57, a paternally imprinted gene. This forms the basis for the diagnosis of hydatidiform moles. There are about 38 paternally imprinted genes. The aim of this study is to determine whether other paternally imprinted genes could also assist in the diagnostic approach of hydatidiform moles. This study comprised of 29 complete moles, 15 partial moles and 17 non-molar abortuses. Immunohistochemical study using the antibodies of paternal-imprinted (RB1, TSSC3 and DOG1) and maternal-imprinted (DNMT1 and GATA3) genes were performed. The antibodies' immunoreactivity was evaluated on various placental cell types, namely cytotrophoblasts, syncytiotrophoblasts, villous stromal cells, extravillous intermediate trophoblasts and decidual cells. TSSC3 and RB1 expression were observed in all cases of partial moles and non-molar abortuses. In contrast, their expression in complete moles was identified in 31% (TSSC3) and 10.3% (RB1), respectively (p < 0.0001). DOG1 was consistently negative in all cell types in all cases. The expressions of maternally imprinted genes were seen in all cases, except for one case of complete mole where GATA3 was negative. Both TSSC3 and RB1 could serve as a useful adjunct to p57 for the discrimination of complete moles from partial moles and non-molar abortuses, especially in laboratories that lack comprehensive molecular service and in cases where p57 staining is equivocal.


Asunto(s)
Mola Hidatiforme , Topos , Animales , Femenino , Humanos , Embarazo , Anticuerpos/metabolismo , Inhibidor p57 de las Quinasas Dependientes de la Ciclina/genética , Inhibidor p57 de las Quinasas Dependientes de la Ciclina/metabolismo , Mola Hidatiforme/diagnóstico , Mola Hidatiforme/genética , Inmunohistoquímica , Topos/metabolismo , Placenta/metabolismo , Proteínas de Unión a Retinoblastoma/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo
6.
Malays J Pathol ; 45(3): 353-362, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38155377

RESUMEN

INTRODUCTION: Hydatidiform mole is one of the gestational trophoblastic disease and comprises complete (CM) and partial moles (PM), which carries a risk of developing persistence disease, invasive mole or choriocarcinoma. MicroRNAs (miRNAs) have been discovered in various tissues, including neoplastic tissues. Its role in the pathogenesis of molar pregnancy or as biomarkers are still largely uncertain. The aim of this study is to identify the differentially expressed miRNAs in CM and PM. MATERIALS AND METHODS: Using next-generation sequencing, the miRNAs profiles of CM (n=3) and PM (n=3) moles, including placenta of non-molar abortus (n=3) as control were determined. The differentially expressed miRNAs between each group were analysed. Subsequently, bioinformatics analysis using miRDB and Targetscan was utilised to predict target genes. RESULTS: We found 10 differentially expressed miRNAs in CMs and PMs, compared to NMAs, namely miR- 518a-5p, miR-423-3p, miR-503-5p, miR-302a-3p, and miR-1323. The other 5 miRNAs were novel, not listed in the known database. The 3 differentially expressed miRNAs in CMs were predicted to commonly target ZTBT46 and FAM73B mRNAs. DISCUSSION: miR-518 was consistently observed to be downregulated in CM versus PM, and CM versus NMA. Further bioinformatic analysis to provide insight into the possible role of these miRNAs in the pathogenesis of HMs, progression of disease and as potential diagnostic biomarkers as well as therapeutic targets for HMs is needed.


Asunto(s)
Coriocarcinoma , Mola Hidatiforme , MicroARNs , Topos , Embarazo , Femenino , Humanos , Animales , Topos/genética , Mola Hidatiforme/genética , MicroARNs/genética , Biomarcadores , Perfilación de la Expresión Génica
7.
Georgian Med News ; (340-341): 170-175, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37805893

RESUMEN

The development of cutaneous melanoma of the skin based on dysplastic nevus is not uncommon. The causes of the progression of nevi to melanomas are numerous and not well understood at present. Certain genetic and epigenetic factors have a major influence on this evolution. We describe a 46-year-old female patient with multiple dermal melanocytic nevi who developed a polypoid melanoma in one of them. After a carefully performed anamnesis, the mole that developed into melanoma was found to be localized in the dorsal area adjacent to the brassiere and underwent permanent and daily mechanical irradiation during the last 6-7 years. Around this mole there were 5 other moles with similar clinical and dermatoscopic morphology, which did not transform into melanomas and were not subjected to mechanical irritation. The patient had a dermatological examination 6 years ago and it was suggested that this lesion has to be surgically removed, which she declined. The patient was treated surgically and the lesion suspicious for cutaneous melanoma was removed in two stages according to the generally accepted AJCC/EJC recommendations. In parallel, 5 additional melanocytic nevi were removed, which histologically had features of dysplastic dermal melanocytic nevi but no signs of progression to melanoma. This article discusses the causes of nevus -associated melanomas and emphasizes the thesis of potential malignant transformation through mechanical irritation - in this case that of the brassiere. The moles localized in this area, although clinically and dermatoscopically inapparent, should be treated surgically. This painless, short-term manipulation has a preventive effect on the future development of cutaneous melanomas.


Asunto(s)
Síndrome del Nevo Displásico , Melanoma , Topos , Nevo Pigmentado , Nevo , Neoplasias Cutáneas , Femenino , Humanos , Persona de Mediana Edad , Animales , Melanoma/complicaciones , Melanoma/diagnóstico , Melanoma/patología , Neoplasias Cutáneas/complicaciones , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/patología , Nevo Pigmentado/complicaciones , Nevo Pigmentado/diagnóstico , Nevo Pigmentado/patología , Nevo/patología , Síndrome , Síndrome del Nevo Displásico/patología , Melanoma Cutáneo Maligno
8.
Mol Biol Evol ; 38(2): 589-605, 2021 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-32986833

RESUMEN

Evolution sometimes proceeds by loss, especially when structures and genes become dispensable after an environmental shift relaxes functional constraints. Subterranean vertebrates are outstanding models to analyze this process, and gene decay can serve as a readout. We sought to understand some general principles on the extent and tempo of the decay of genes involved in vision, circadian clock, and pigmentation in cavefishes. The analysis of the genomes of two Cuban species belonging to the genus Lucifuga provided evidence for the largest loss of eye-specific genes and nonvisual opsin genes reported so far in cavefishes. Comparisons with a recently evolved cave population of Astyanax mexicanus and three species belonging to the Chinese tetraploid genus Sinocyclocheilus revealed the combined effects of the level of eye regression, time, and genome ploidy on eye-specific gene pseudogenization. The limited extent of gene decay in all these cavefishes and the very small number of loss-of-function mutations per pseudogene suggest that their eye degeneration may not be very ancient, ranging from early to late Pleistocene. This is in sharp contrast with the identification of several vision genes carrying many loss-of-function mutations in ancient fossorial mammals, further suggesting that blind fishes cannot thrive more than a few million years in cave ecosystems.


Asunto(s)
Relojes Circadianos/genética , Peces/genética , Mutación con Pérdida de Función , Topos/genética , Pigmentación/genética , Visión Ocular/genética , Animales , Cuevas , Seudogenes , Selección Genética , Pez Cebra
9.
Genetica ; 150(5): 317-325, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36029420

RESUMEN

The complete mitogenome sequence of Talpa martinorum, a recently described Balkan endemic mole, was assembled from next generation sequence data. The mitogenome is similar to that of the three other Talpa species sequenced to date, being 16,835 bp in length, and containing 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes, an origin of L-strand replication, and a control region or D-loop. Compared to other Talpa mitogenomes sequenced to date, that of T. martinorum differs in the length of D-loop and stop codon usage. TAG and T-- are the stop codons for the ND1 and ATP8 genes, respectively, in T. martinorum, whilst TAA acts as a stop codon for both ND1 and ATP8 in the other three Talpa species sequenced. Phylogeny reconstructions based on Maximum Likelihood and Bayesian inference analyses yielded phylogenies with similar topologies, demonstrating that T. martinorum nests within the western lineage of the genus, being closely related to T. aquitania and T. occidentalis.


Asunto(s)
Genoma Mitocondrial , Topos , Animales , Teorema de Bayes , Codón de Terminación , Topos/genética , Filogenia , ARN de Transferencia/genética
10.
Sensors (Basel) ; 22(3)2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-35161868

RESUMEN

Skin moles and lesions can be the first signs of severe skin diseases such as cancer. This paper presents the development of an end-user device capable of capturing images, segmentation and diagnosis of moles by using the ABCD rule, which stands for analyzing moles' parameters as: asymmetry, border, color, and diameter. These are the main mole characteristics that doctors look at, each of them having a different factor of importance, and depending on these an accurate diagnosis can be given. For the hardware, we developed a small and compact device that can be manipulated easily by anyone without knowledge of medicine, in which we considered a custom-designed 3D enclosure with two white LEDs to control the light. The device has the role of facilitating analysis of the suspicious moles regularly at home, even if only from an indicative and not from a medical point of view. The developed PC software permits the storage of the images in a local database for easy tracking and analysis in time. The image processing developed for the ABCD rule is incorporated into the PC software and tested extensively on the international PH2 database with skin melanoma images to validate our segmentation and criteria evaluation. Using the developed device, we captured mole images for patients, who also took a medical examination by a specialist using the standard dermatoscope. Therefore, we obtained our own database containing 26 images for which we have also the specialists' diagnosis. The performance evaluation measures obtained using our device are-Accuracy: 0.92, Precision: 1.0, Recall: 0.92, F1-score: 0.96.


Asunto(s)
Melanoma , Topos , Nevo Pigmentado , Neoplasias Cutáneas , Animales , Humanos , Piel , Neoplasias Cutáneas/diagnóstico por imagen
11.
Int J Mol Sci ; 24(1)2022 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-36614154

RESUMEN

The aim of the present work was to obtain microbial lipids (single-cell oils and SCOs) from oleaginous yeast cultivated on biodiesel-derived glycerol and subsequently proceed to the enzymatic synthesis of high-value biosurfactant-type molecules in an aqueous medium, with SCOs implicated as acyl donors (ADs). Indeed, the initial screening of five non-conventional oleaginous yeasts revealed that the most important lipid producer was the microorganism Cryptococcus curvatus ATCC 20509. SCO production was optimised according to the nature of the nitrogen source and the initial concentration of glycerol (Glyc0) employed in the medium. Lipids up to 50% w/w in dry cell weight (DCW) (SCOmax = 6.1 g/L) occurred at Glyc0 ≈ 70 g/L (C/N ≈ 80 moles/moles). Thereafter, lipids were recovered and were subsequently used as ADs in the N-acylation reaction catalysed by aminoacylases produced from Streptomyces ambofaciens ATCC 23877 under aqueous conditions, while Candida antarctica lipase B (CALB) was used as a reference enzyme. Aminoacylases revealed excellent activity towards the synthesis of acyl-lysine only when free fatty acids (FAs) were used as the AD, and the rare regioselectivity in the α-amino group, which has a great impact on the preservation of the functional side chains of any amino acids or peptides. Aminoacylases presented higher α-oleoyl-lysine productivity and final titer (8.3 g/L) with hydrolysed SCO than with hydrolysed vegetable oil. The substrate specificity of both enzymes towards the three main FAs found in SCO was studied, and a new parameter was defined, viz., Specificity factor (Sf), which expresses the relative substrate specificity of an enzyme towards a FA present in a FA mixture. The Sf value of aminoacylases was the highest with palmitic acid in all cases tested, ranging from 2.0 to 3.0, while that of CALB was with linoleic acid (0.9-1.5). To the best of our knowledge, this is the first time that a microbial oil has been successfully used as AD for biosurfactant synthesis. This bio-refinery approach illustrates the concept of a state-of-the-art combination of enzyme and microbial technology to produce high-value biosurfactants through environmentally friendly and economically sound processes.


Asunto(s)
Glicerol , Topos , Animales , Glicerol/metabolismo , Aminoácidos/metabolismo , Lisina/metabolismo , Topos/metabolismo , Levaduras/metabolismo , Aceites de Plantas/metabolismo , Biocombustibles , Ácidos Grasos/metabolismo
12.
J Exp Biol ; 224(19)2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34533564

RESUMEN

Star-nosed moles (Condylura cristata) have an impressive diving performance and burrowing lifestyle, yet no ventilatory data are available for this or any other talpid mole species. We predicted that, like many other semi-aquatic and fossorial small mammals, star-nosed moles would exhibit: (i) a blunted (i.e. delayed or reduced) hypoxic ventilatory response, (ii) a reduced metabolic rate and (iii) a lowered body temperature (Tb) in hypoxia. We thus non-invasively measured these variables from wild-caught star-nosed moles exposed to normoxia (21% O2) or acute graded hypoxia (21-6% O2). Surprisingly, star-nosed moles did not exhibit a blunted HVR or decreased Tb in hypoxia, and only manifested a significant, albeit small (<8%), depression of metabolic rate at 6% O2 relative to normoxic controls. Unlike small rodents inhabiting similar niches, star-nosed moles are thus intolerant to hypoxia, which may reflect an evolutionary trade-off favouring the extreme sensory biology of this unusual insectivore.


Asunto(s)
Buceo , Topos , Animales , Temperatura Corporal , Eulipotyphla , Hipoxia
13.
Mol Phylogenet Evol ; 143: 106667, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31676418

RESUMEN

Golden moles (Family Chrysochloridae) are small subterranean mammals, endemic to sub-Saharan Africa, and many of the 21 species are listed as threatened on the IUCN Red List. Most species have highly restricted ranges; however two species, the Hottentot golden mole (Amblysomus hottentotus) and the Cape golden mole (Chrysochloris asiatica) have relatively wide ranges. We recently uncovered cryptic diversity within A. hottentotus, through a phylogeographic analysis of this taxon using two mitochondrial gene regions and a nuclear intron. To further investigate this cryptic diversity, we generated nuclear SNP data from across the genome of A. hottentotus, by means of double-digest restriction-site associated DNA sequencing (ddRADSeq), and mapped reads to the Cape golden mole genome. We conducted a phylogenetic analysis and investigated population differentiation. Our results support the distinctiveness of A. h. meesteri. Furthermore, we provide evidence from nuclear SNPs in support of our previous finding that Central coastal samples represent a unique cryptic lineage that is highly divergent from A. h. pondoliae farther south. Although mtDNA suggests that Umtata may represent a unique lineage sister to A. h. longiceps, mito-nuclear discordance from our RADseq data indicate that these samples may instead be closer to A. h. pondoliae, and therefore may not represent a distinct lineage. We stress the importance of recognizing that understudied populations, such as that of Umtata, may represent populations or ESUs under threat and in need of conservation attention. We present a high-quality filtered SNP dataset, comprising thousands of SNPs, which may serve as a useful resource for future golden mole studies. We have thus added to the growing body of research demonstrating the power and utility of RADseq to investigate population differentiation.


Asunto(s)
Euterios/clasificación , Topos/clasificación , Animales , ADN Mitocondrial , Euterios/genética , Topos/genética , Filogenia , Filogeografía , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ADN , Sudáfrica
14.
Parasitol Res ; 119(5): 1583-1595, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32107619

RESUMEN

Results of the present study provide ultrastructural evidence that miracidial morphogenesis is fully completed within the intrauterine eggs while in the most posterior uterine regions of Ityogonimus lorum, a digenean parasite of an Iberian mole, Talpa occidentalis (Eulipotyphla, Talpidae). Using transmission electron microscopy (TEM), the ultrastructural characteristics of diverse cell types and their organelles of these developing embryos and fully formed miracidia within the eggshell were examined. The eggshell and embryonic envelopes are similar to those described previously by many authors for other digeneans. However, the developing miracidia are unique among previously described digeneans in possessing transitory cilia during larvigenesis, but completely lacking cilia in fully formed miracidium larvae. The evidence for completion of miracidial maturation in intrauterine eggs is based on the presence of the following structures: (1) transitional stage of ciliated differentiating miracidial epithelium; (2) apical and lateral glands, characteristic for digenean miracidia; and (3) fully developed germinative cells grouped together in the germinative sac localized in the posterior region of the miracidium. The protonephridial system with its characteristic flame cells and the nervous system with diverse types of neurons and nerve centers, which are characteristic for other digenean species reported until now, are absent from all these developmental stages of I. lorum. Based on these observations, we hypothesize that the life cycle of I. lorum is entirely terrestrial, involving passive transmission by ingestion of eggs containing unciliated miracidia to the first intermediate host.


Asunto(s)
Desarrollo Embrionario/fisiología , Morfogénesis/fisiología , Trematodos/embriología , Trematodos/ultraestructura , Infecciones por Trematodos/transmisión , Animales , Femenino , Histocitoquímica , Larva/anatomía & histología , Larva/crecimiento & desarrollo , Microscopía Electrónica de Transmisión , Topos/parasitología , Trematodos/clasificación , Útero/parasitología
15.
BMC Evol Biol ; 19(1): 179, 2019 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-31510915

RESUMEN

BACKGROUND: Understanding the mechanisms promoting or constraining morphological diversification within clades is a central topic in evolutionary biology. Ecological transitions are of particular interest because of their influence upon the selective forces and factors involved in phenotypic evolution. Here we focused on the humerus and mandibles of talpid moles to test whether the transition to the subterranean lifestyle impacted morphological disparity and phenotypic traits covariation between these two structures. RESULTS: Our results indicate non-subterranean species occupy a significantly larger portion of the talpid moles morphospace. However, there is no difference between subterranean and non-subterranean moles in terms of the strength and direction of phenotypic integration. CONCLUSIONS: Our study shows that the transition to a subterranean lifestyle significantly reduced morphological variability in talpid moles. However, this reduced disparity was not accompanied by changes in the pattern of traits covariation between the humerus and the mandible, suggesting the presence of strong phylogenetic conservatism within this pattern.


Asunto(s)
Ecosistema , Topos/anatomía & histología , Puntos Anatómicos de Referencia , Animales , Húmero/anatomía & histología , Análisis de los Mínimos Cuadrados , Estilo de Vida , Mandíbula/anatomía & histología , Topos/clasificación , Fenotipo , Filogenia , Análisis de Componente Principal , Carácter Cuantitativo Heredable
16.
J Exp Biol ; 222(Pt 4)2019 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-30718373

RESUMEN

The interplay between morphological specialization and kinematic flexibility is important for organisms that move between habitats within different substrates. Burrowing is energetically expensive and requires substantial interaction with soil to dislodge and transport it. True moles (Talpidae) have extraordinary forelimb morphologies and a unique ability to dig in loose as well as compact soils, yet we know little of how moles coordinate their forelimb joint kinematics when digging in soils of different compactness. Using marker-based X-ray Reconstruction of Moving Morphology (XROMM), we tested the hypothesis that moles burrow using different forelimb kinematics in loose and compact substrates. We predicted that moles raise mounds of loose soil by performing powerful compacting strokes mainly with long-axis rotation of the humerus (i.e. pronation/supination), but shear compact soil away by performing scratching strokes involving amplified elbow extension, similar to most scratching diggers. We also predicted that in both types of substrate, moles displace soil rearward like other mammalian diggers. Our results support our hypothesis but not the predictions. Eastern moles (Scalopus aquaticus) move substrates upward using compacting strokes in loose substrates and outward from the body midline using scratching strokes in compact substrates; unlike the digging strokes of most mammalian forelimb diggers, the power-stroke of moles itself does not displace substrates directly rearward. Compacting and scratching strokes involve similar ranges of humeral pronation and retraction at the scapulohumeral (shoulder) joint, yet the movements at the elbow and carpal joints differ. Our results demonstrate that the combination of stereotypic movements of the shoulder joint, where the largest digging muscles are located, and flexibility in the elbow and carpal joints makes moles extremely effective diggers in both loose and compact substrates.


Asunto(s)
Miembro Anterior/fisiología , Topos/fisiología , Movimiento , Articulación del Hombro/fisiología , Animales , Fenómenos Biomecánicos
17.
Biol Lett ; 15(10): 20190503, 2019 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-31662063

RESUMEN

A recurring theme in the evolution of tetrapods is the shift from sprawling posture with laterally orientated limbs to erect posture with the limbs extending below the body. However, in order to invade particular locomotor niches, some tetrapods secondarily evolved a sprawled posture. This includes moles, some of the most specialized digging tetrapods. Although their forelimb anatomy and posture facilitates burrowing, moles also walk long distances to forage for and transport food. Here, we use X-ray Reconstruction Of Moving Morphology (XROMM) to determine if the mole humerus rotates around its long axis during walking, as it does when moles burrow and echidnas walk, or alternatively protracts and retracts at the shoulder in the horizontal plane as seen in sprawling reptiles. Our results reject both hypotheses and demonstrate that forelimb kinematics during mole walking are unusual among those described for tetrapods. The humerus is retracted and protracted in the parasagittal plane above, rather than below the shoulder joint and the 'false thumb', a sesamoid bone (os falciforme), supports body weight during the stance phase, which is relatively short. Our findings broaden our understanding of the diversity of tetrapod limb posture and locomotor evolution, demonstrate the importance of X-ray-based techniques for revealing hidden kinematics and highlight the importance of examining locomotor function at the level of individual joint mobility.


Asunto(s)
Topos , Caminata , Animales , Fenómenos Biomecánicos , Miembro Anterior , Locomoción , Pulgar
18.
Mol Biol Evol ; 34(1): 78-87, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27795230

RESUMEN

The mammalian family Talpidae (moles, shrew moles, desmans) is characterized by diverse ecomorphologies associated with terrestrial, semi-aquatic, semi-fossorial, fossorial, and aquatic-fossorial lifestyles. Prominent specializations involved with these different lifestyles, and the transitions between them, pose outstanding questions regarding the evolutionary history within the family, not only for living but also for fossil taxa. Here, we investigate the phylogenetic relationships, divergence times, and biogeographic history of the family using 19 nuclear and 2 mitochondrial genes (∼16 kb) from ∼60% of described species representing all 17 genera. Our phylogenetic analyses help settle classical questions in the evolution of moles, identify an ancient (mid-Miocene) split within the monotypic genus Scaptonyx, and indicate that talpid species richness may be nearly 30% higher than previously recognized. Our results also uniformly support the monophyly of long-tailed moles with the two shrew mole tribes and confirm that the Gansu mole is the sole living Asian member of an otherwise North American radiation. Finally, we provide evidence that aquatic specializations within the tribes Condylurini and Desmanini evolved along different morphological trajectories, though we were unable to statistically reject monophyly of the strictly fossorial tribes Talpini and Scalopini.


Asunto(s)
Topos/genética , Musarañas/genética , Animales , Evolución Biológica , Clasificación/métodos , Bases de Datos de Ácidos Nucleicos , Variación Genética , Filogenia , Análisis de Secuencia de ADN/métodos , Especificidad de la Especie
19.
Genetica ; 146(4-5): 415-423, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30145730

RESUMEN

The complete mitogenome of Talpa occidentalis, the Iberian mole, was sequenced using a combination of the Illumina and Sanger methods. The 16,962 bp genome obtained contains 13 protein-coding genes, 22 transfer RNAs, 2 ribosomal RNAs, and a control region. Thirty-seven identical repetitions of a 10-nucleotide (CACACGTACG) repeat element were identified in the non-coding control region (D-loop). The number, order, and orientation of the mitochondrial genes are the same as in T. europaea, the only mitogenome published so far for this genus. These two mitogenomes differ only at the repeat element included in the control region. The phylogeny obtained for the Talpidae species using the protein-coding genes of these mitogenomes agrees with the current classification of this family.


Asunto(s)
Topos/genética , Animales , Composición de Base/genética , Secuencia de Bases , Especies en Peligro de Extinción , Genes Mitocondriales , Genoma Mitocondrial/genética , Filogenia , Portugal , ARN Ribosómico/genética , ARN de Transferencia/genética , Análisis de Secuencia de ADN/métodos , España
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