scholarly journals Molecular diagnostic based on 18S rDNA and supplemental taxonomic data of the cnidarian coelozoic Ceratomyxa (Cnidaria, Myxosporea) and comments on the intraspecific morphological variation

2021 ◽  
Vol 97 (2) ◽  
pp. 307-314
Author(s):  
Fabricio B. Sousa ◽  
Tiago Milanin ◽  
André C. Morandini ◽  
Luis L. Espinoza ◽  
Anai Flores-Gonzales ◽  
...  
Keyword(s):  
18S Rdna ◽  
Amazon Basin ◽  
Morphological Plasticity ◽  
Original Description ◽  
Base Change ◽  
Molecular Diagnostic ◽  
Single Nucleotide ◽  
Morphological Differences ◽  
Intraspecific Morphological Variation

Ceratomyxa amazonensis is a cnidarian myxosporean originally described with strongly arcuate crescent-shaped myxospores, absence of vegetative stages and infecting Symphysodon discus, an important Amazonian ornamental fish in the aquarium industry. As part of a long-term investigation concerning myxosporeans that infect discus fish Symphysodon spp. from different rivers of the Amazon Basin, thirty specimens of S. discus collected from Unini River were examined. Plasmodial vegetative stages therefrom were found freely floating in the bile of gall bladders from eighteen fish. Mature myxospores were slightly crescent-shaped, measuring 4.72 ± 0.1 (4.52–4.81) μm in length, 24.2 ± 0.4 (23.9–25.3) μm in thickness with polar capsules 2.31 ± 0.1 (2.29–2.33) μm in length and 2.15 ± 0.1 (2.13–2.17) μm in width. Strong morphological differences were observed between the newly isolated myxospores obtained and the previously described C. amazonensis; however, molecular assessment, based on 18S rDNA, revealed a high similarity (99.91%), with only a single nucleotide base change. This study provides new data, expanding the original description of the species with a discussion on differences in myxospore-morphology in the context of intraspecific morphological plasticity.

Morphology and phylogeny of Halamphora yongxingensis sp. nov. (Bacillariophyta), a new marine benthic diatom isolated from Yongxing Island, South China Sea

Phytotaxa ◽  
2015 ◽  
Vol 195 (1) ◽  
pp. 53 ◽  
Author(s):  
Hai-ying Jiang ◽  
Chao-qun Hu ◽  
Hai-peng Yang ◽  
Lv-ping Zhang ◽  
Peng-fei Peng ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
South China Sea ◽  
South China ◽  
18S Rdna ◽  
Phylogenetic Analyses ◽  
Light And Electron Microscopy ◽  
Benthic Diatom ◽  
Rbcl Gene ◽  
China Sea ◽  
Morphological Differences

Halamphora yongxingensis sp. nov., a marine benthic diatom isolated from an intertidal reef around the Yongxing Island, South China Sea (16° 58’ 43.3” N, 112° 14’ 41.7” E), is described in this study on the basis of light and electron microscopy. This diatom is also compared with related taxa such as Halamphora subturgida (Hustedt) Levkov and Amphora subtropica Wachnicka & Gaiser. In addition, phylogenetic analyses based on 18S rDNA and rbcL gene were also conducted. The results revealed that H. yongxingensis was clustered into the Halamphora clade, closely related to Halamphora montana (Krasske) Levkov. We discuss morphological differences between H. yongxingensis and H. montana.

scholarly journals A gain-of-function single nucleotide variant creates a new promoter which acts as an orientation-dependent enhancer-blocker

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Yavor K. Bozhilov ◽  
Damien J. Downes ◽  
Jelena Telenius ◽  
A. Marieke Oudelaar ◽  
Emmanuel N. Olivier ◽  
...  
Keyword(s):  
Gene Expression ◽  
Genetic Diseases ◽  
Regulatory Elements ◽  
Base Change ◽  
Dependent Manner ◽  
Globin Genes ◽  
Single Nucleotide Variants ◽  
Single Nucleotide ◽  
Super Enhancer ◽  
Single Base Change

AbstractMany single nucleotide variants (SNVs) associated with human traits and genetic diseases are thought to alter the activity of existing regulatory elements. Some SNVs may also create entirely new regulatory elements which change gene expression, but the mechanism by which they do so is largely unknown. Here we show that a single base change in an otherwise unremarkable region of the human α-globin cluster creates an entirely new promoter and an associated unidirectional transcript. This SNV downregulates α-globin expression causing α-thalassaemia. Of note, the new promoter lying between the α-globin genes and their associated super-enhancer disrupts their interaction in an orientation-dependent manner. Together these observations show how both the order and orientation of the fundamental elements of the genome determine patterns of gene expression and support the concept that active genes may act to disrupt enhancer-promoter interactions in mammals as in Drosophila. Finally, these findings should prompt others to fully evaluate SNVs lying outside of known regulatory elements as causing changes in gene expression by creating new regulatory elements.

AN ANALYSIS OF INTERSPECIFIC AND INTRASPECIFIC MORPHOLOGICAL DIFFERENCES IN TWO CLOSELY RELATED SPECIES OF AMBLYSEIUS BERLESE USING METHODS OF NUMERICAL TAXONOMY (ACARINA: PHYTOSEHDAE)

1977 ◽  
Vol 109 (12) ◽  
pp. 1605-1618 ◽  
Author(s):  
D.A. Chant ◽  
R.I.C. Hansell ◽  
H.J. Rowell
Keyword(s):  
Host Plant ◽  
Morphological Variation ◽  
Related Species ◽  
Numerical Taxonomy ◽  
Valid Species ◽  
Closely Related Species ◽  
Multivariate Tests ◽  
Taxonomic Methods ◽  
Morphological Differences ◽  
Intraspecific Morphological Variation

AbstractMorphological variation between two closely related species in the genus Amblyseius Berlese was examined by numerical taxonomic methods. Multivariate tests indicated that A. canadensis Chant and Hansell and A. novaescotiae (Chant) represent two separate and distinct morphological groups. This supports their taxonomic retention as valid species. Intraspecific morphological variation was also examined and found to be correlated with climatic and host plant variables.

scholarly journals New morphological data and molecular diagnostic of Henneguya friderici (Myxozoa: Myxobolidae), a parasite of Leporinus friderici (Osteichthyes: Anostomidae) from southeastern Brazil

2017 ◽  
Vol 26 (1) ◽  
pp. 81-88 ◽  
Author(s):  
Letícia Poblete Vidal ◽  
José Luis Luque
Keyword(s):  
Body Length ◽  
18S Rdna ◽  
Genetic Similarity ◽  
Morphological Data ◽  
Southeastern Brazil ◽  
Molecular Diagnostic ◽  
Similarity Analysis ◽  
Rdna Sequencing ◽  
The Family ◽  
Gill Filaments

Abstract The myxozoan Henneguya friderici is a parasite of the gills, intestine, kidney and liver of Leporinus friderici, a characiform fish belonging to the family Anostomidae. Forty-two specimens of L. friderici that had been caught in the Mogi Guaçú River, state of São Paulo, were studied. Elongated white plasmodia were found in the gill filaments of 10 host specimens (24%). The mature spores had an ellipsoidal body with polar capsules of equal size and caudal length greater than body length. This study also described 18S rDNA sequencing of H. friderici infecting the gill filaments. This produced a sequence of 1050 bp that demonstrated significant genetic differences with previously described species of Henneguya. Similarity analysis using sequences from species that clustered closest to those produced by this study showed that the species with greatest genetic similarity to H. friderici was H. leporinicola, with 94% similarity.

scholarly journals RAPELD: a modification of the Gentry method for biodiversity surveys in long-term ecological research sites

2005 ◽  
Vol 5 (2) ◽  
pp. 19-24 ◽  
Author(s):  
William E. Magnusson ◽  
Albertina P. Lima ◽  
Regina Luizão ◽  
Flávio Luizão ◽  
Flávia R. C. Costa ◽  
...  
Keyword(s):  
Land Use ◽  
Land Use Planning ◽  
Amazon Basin ◽  
Local People ◽  
Ecological Research ◽  
Original Design ◽  
Biological Surveys ◽  
Incomplete Coverage ◽  
Long Term Ecological Research

Our objectives were to develop a method that would be appropriate for long-term ecological studies, but that would permit rapid surveys to evaluate biotic complementarity and land-use planning in Amazonia. The Amazon basin covers about 7 million km². Therefore, even a sparse coverage, with one sample site per 10.000 km², would require about 700 sampling sites. Financial considerations limit the number of sites and investment at each site, but incomplete coverage makes evaluation of biotic complementarity difficult or impossible (Reddy & Dávalos 2003). Our next challenge is to install similar systems throughout Amazonia. The cost, based on modification of Al Gentry's original design is moderate (less than US$ 50.000 per site if it is not necessary to immediately identify all vascular plants in plots) and we can obtain RAP results for most taxa in the short term at much lower cost. However, biological surveys will only be relevant if the local people participate and the surveys serve as much to teach the local communities about the value of their natural resources as they serve to teach the international community about biodiversity. Therefore, we want to see each site run as a long-term ecological research project by local people and institutions. Biological surveys are an important tool in land-use planning, but only the local people can implement those plans.

scholarly journals A Novel Distinct Genetic Variant of Tomato Torrado Virus with Substantially Shorter RNA1-Specific 3’untranslated Region (3’UTR)

Plants ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 2454
Author(s):  
Marta Budziszewska ◽  
Przemysław Wieczorek
Keyword(s):  
Amino Acid ◽  
Genetic Variability ◽  
Untranslated Region ◽  
Genetic Variant ◽  
Sequencing Data ◽  
Sequence Analyses ◽  
Nucleotide Substitutions ◽  
Systemic Necrosis ◽  
Single Nucleotide

Tomato torrado virus (ToTV) induces severe systemic necrosis in Solanum lycopersicum. This work aimed at describing the genetic variability of necrosis-inducing ToTV-Wal’17 collected in 2017, derived from the ToTV-Wal’03 after long-term passages in plants. Sequence analyses of the ToTV-Wal’17 indicated twenty-eight single nucleotide substitutions in coding sequence of both RNAs, twelve of which resulted in amino acid changes in viral polyproteins. Moreover the sequencing data revealed that the 3’UTR of ToTV-Wal’17 RNA1 was 394 nts shorter in comparison to Wal’03. The performed sequence analyses revealed that 3’UTR of RNA1 of ToTV-Wal’17 is the most divergent across all previously described European isolates.

Fluvial Perturbance in the Western Amazon Basin: Regulation by Long-Term Sub-Andean Tectonics

Science ◽  
1987 ◽  
Vol 238 (4832) ◽  
pp. 1398-1401 ◽  
Author(s):  
M. E. RASANEN ◽  
J. S. SALO ◽  
R. J. KALLIOLA
Keyword(s):  
Amazon Basin

Effects of forest fragmentation on neotropical fauna: current research and data availability

1995 ◽  
Vol 3 (2) ◽  
pp. 191-211 ◽  
Author(s):  
Holly L. Offerman ◽  
Virginia H. Dale ◽  
Scott M. Pearson ◽  
Robert V. O'Neill ◽  
Richard O. Bierregaard Jr.
Keyword(s):  
Forest Fragmentation ◽  
Amazon Basin ◽  
Data Availability ◽  
Forest Fragments ◽  
Forest Patches ◽  
Neotropical Fauna ◽  
Using Data ◽  
Spatially Explicit Data ◽  
Biological Dynamics

Tropical deforestation often produces landscapes characterized by isolated patches of forest habitat surrounded by pasture, agriculture, or regrowth vegetation. Both the size and the distribution of these forest patches may influence the long-term persistence of faunal species. There is, therefore, a pressing need to understand faunal responses to patterns of forest fragmentation in tropical systems. The Biological Dynamics of Forest Fragments Project (BDFFP) provides a wealth of autecological information and spatially explicit data describing habitat use and movement of fauna between Amazonian forest fragments. Using data from the BDFFP and other studies in the Amazon Basin, this paper reviews the information available on tropical insects, frogs, birds, primates, and other mammals that can be used to identify and classify species most at risk for extirpation in fragmented forests.Key words: Amazonia, habitat fragmentation, rainforest, fauna, Biological Dynamics of Forest Fragmentation Project.

scholarly journals River Discharge Estimation based on Satellite Water Extent and Topography: An Application over the Amazon

2019 ◽  
Vol 20 (9) ◽  
pp. 1851-1866 ◽  
Author(s):  
Dinh Thi Lan Anh ◽  
Filipe Aires
Keyword(s):  
River Discharge ◽  
Amazon Basin ◽  
Water Cycle ◽  
Large River ◽  
Water Volume ◽  
Discharge Estimation ◽  
Three Rivers ◽  
Storage Change

Abstract River discharge (RD) estimates are necessary for many applications, including water management, flood risk, and water cycle studies. Satellite-derived long-term GIEMS-D3 surface water extent (SWE) maps and HydroSHEDS data, at 90-m resolution, are here used to estimate several hydrological quantities at a monthly time scale over a few selected locations within the Amazon basin. Two methods are first presented to derive the water level (WL): the “hypsometric curve” and the “histogram cutoff” approaches at an 18 km × 18 km resolution. The obtained WL values are interpolated over the whole water mask using a bilinear interpolation. The two methods give similar results and validation with altimetry is satisfactory, with a correlation ranging from 0.72 to 0.89 in the seven considered stations over three rivers (i.e., Wingu, Negro, and Solimoes Rivers). River width (RW) and water volume change (WVC) are also estimated. WVC is evaluated with GRACE total water storage change, and correlations range from 0.77 to 0.88. A neural network (NN) statistical model is then used to estimate the RD based on four predictors (SWE, WL, WVC, and RW) and on in situ RD measurements. Results compare well to in situ measurements with a correlation of about 0.97 for the raw data (and 0.84 for the anomalies). The presented methodologies show the potential of historical satellite data (the combination of SWE with topography) to help estimate RD. Our study focuses here on a large river in the Amazon basin at a monthly scale; additional analyses would be required for other rivers, including smaller ones, in different environments, and at higher temporal scale.

scholarly journals Polymorphism of the complement 5 gene is associated with large artery atherosclerosis stroke in Chinese patients

2016 ◽  
Vol 74 (11) ◽  
pp. 881-886 ◽  
Author(s):  
Hui Wu ◽  
Yingfeng Weng ◽  
Lan Zheng ◽  
Huanyin Li ◽  
Qi Gong ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Chinese Patients ◽  
Large Artery ◽  
Nucleotide Polymorphism ◽  
Term Outcome ◽  
Single Nucleotide ◽  
Long Term Outcome ◽  
Risk Predictors ◽  
The Complement System

ABSTRACT The complement system has been confirmed to play an increasingly important role in ischemic stroke (IS). This study aimed to determine whether the single-nucleotide polymorphism of the complement 5 (C5) gene independently influences the occurrence, severity, and long-term outcome of IS in Chinese patients. Methods C5 rs17611 genetic variants were investigated in 494 IS patients and 330 control individuals .Ischemic stroke was classified into subtypes and patients were assessed 90 days post-stroke with the modified Rankin Scale to determine stroke outcome. Results The presence of C5 polymorphism was associated with the incidence of large artery atherosclerosis (LAA)-subtype IS (n =2 00; p = 0.031), which even persisted after adjustment for covariates (OR = 1.518; 95%CI = 1.093–2.018; p = 0.013). However, no association was found between genotypes and the severity and outcome of stroke (p = 0.978; p = 0.296). Conclusions The C5 polymorphism might contribute to the risk of LAA-subtype IS independently of other known risk predictors.

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