scholarly journals Molecular tools for identification and classification of Myxozoan parasites (Cnidaria: Myxosporea) in India: Current status

2021 ◽  
Vol 13 (1) ◽  
pp. 51-58
Author(s):  
Abhishek Gupta ◽  
Anshu Chaudhary ◽  
Anju Tyagi ◽  
Bindu Sharma ◽  
Hridaya S. Singh
Keyword(s):  
Molecular Markers ◽  
Large Subunit ◽  
Molecular Taxonomy ◽  
Morphological Characteristics ◽  
Molecular Techniques ◽  
Classification Systems ◽  
Morphological Data ◽  
Current Status ◽  
Nominal Species ◽  
Molecular Tools

A substantial literature on myxosporea has been published to date using morphological characters and specificity of host tissue. Currently, there are some 2400 nominal species of myxosporea classified to 17 families and 64 genera. Approximately 300 species have been described from India and most of them have been described solely on the basis of morphological characteristics. Molecular markers like small subunit ribosomal (SSU) and large subunit ribosomal (LSU) DNA have been used worldwide for the identification and validation of fish myxosporeans. Maximum likelihood phylogenetic tree based on SSU rDNA sequences was used to study the phylogenetic relationship among myxosporeans infecting Indian fishes. Myxospore phylogenies disagree with traditional spore-based classification systems, probably due to extreme plasticity in myxospores morphologies that have resulted in extensive convergence. Morphological similarities exist among myxosporea that encounter several problems in categorizing them. That’s why present-day research has shifted to molecular techniques for identification and correct systematics of myxosporeans. Molecular studies of myxozoans in India are still scarce and in infancy. To address persisting taxonomic and phylogenetic discrepancies, validation of these species by molecular tools is needed, because earlier species were reported only on the basis of morphological data. Therefore, the present study has summarized existing molecular data and current status of molecular taxonomy of myxosporeans parasitizing fresh and marine water fishes of India along with the approaches of myxozoan phylogenetics and information about the molecular markers, their interpretation in the identification of myxozoans parasitizing fishes.

The genus Cystoseira s.l. (Ochrophyta, Fucales, Sargassaceae) in the Black Sea: morphological variability and molecular taxonomy of Gongolaria barbata and endemic Ericaria crinita f. bosphorica comb. nov.

Phytotaxa ◽  
2021 ◽  
Vol 480 (1) ◽  
pp. 1-21
Author(s):  
SOFIA S. SADOGURSKA ◽  
JOÃO NEIVA ◽  
ANNALISA FALACE ◽  
ESTER A. SERRÃO ◽  
ÁLVARO ISRAEL
Keyword(s):  
Mediterranean Sea ◽  
Black Sea ◽  
Molecular Taxonomy ◽  
Morphological Variability ◽  
Morphological Characteristics ◽  
Molecular Data ◽  
Morphological Data ◽  
The Black Sea ◽  
Morphological Identification ◽  
Additional Tool

Brown algae of the genus Cystoseira sensu lato form the most diverse and productive marine ecosystems throughout the Mediterranean Sea and have equal roles also in the Black Sea where they have been decreasing in the recent years. The taxonomy of Cystoseira s.l. taxa from the Black Sea is still not well understood, and questions arise when related taxa have to be delimited. In addition to morphological descriptions, this study provides for the first time molecular data of the Black Sea Cystoseira s.l. distinct morphologies as an additional tool to clarify their identities and phylogenetic affinities. The analysis of two mitochondrial markers (cytochrome oxidase subunit 1—COI, and 23S-tRNAVal intergenic spacer—mt-spacer) showed that Cystoseira s.l. specimens from the Black Sea belong to two recently resurrected genera, namely Gongolaria and Ericaria. Molecular data confirm the morphological identification of G. barbata, which is characterized by high morphological plasticity in the Black Sea. The morphological data presented in this study support the transition of G. barbata to the genus Gongolaria, which was previously proposed based solely on genetic data. For the Black Sea endemic taxon C. bosphorica, sequence divergence suggests conspecificity with Mediterranean Sea species E. crinita and E. barbatula. However, considering original morphological characteristics of the taxon, its geographical isolation, and endemism, the new combination Ericaria crinita f. bosphorica comb. nov. is proposed.

Molecular taxonomy of the Anadenobolus excisus (Diplopoda : Spirobolida : Rhinocricidae) species-group on the Caribbean island of Jamaica

2003 ◽  
Vol 17 (4) ◽  
pp. 515 ◽  
Author(s):  
Jason E. Bond ◽  
Petra Sierwald
Keyword(s):  
Molecular Taxonomy ◽  
Molecular Data ◽  
Species Group ◽  
Morphological Data ◽  
Rrna Gene ◽  
Nominal Species ◽  
Caribbean Island ◽  
The Caribbean ◽  
The 16S Rrna Gene ◽  
Mtdna Genealogy

This paper documents the mtDNA genealogy and molecular taxonomy of the Anadenobolus excisus millipede species-group on the island of Jamaica. This endemic species-group originally comprised two nominal species, A. excisus (Karsch) and A. holomelanus Pocock. However, the latter species was considered by Hoffman likely to be a subspecies of the former, owing to their overall morphological and gonopodal similarity (the secondary sexual features most commonly used to delineate millipede species). We summarise molecular and morphological data that paints a rather different picture of the diversity in this group. Based on the 16S rRNA gene of the mitochondrion and a comparative analysis of millipede size (reported here and elsewhere), we find that this species-group comprises at least three sibling species, one of which, A. dissimulans, sp. nov., is newly described. The study documents the first myriapod species diagnosed on the basis of molecular data.

scholarly journals Current Status of Mapping Quantitative Trait Loci (QTL) for Different Traits and Marker Assisted Breeding in Chickpea (Cicer arietinum L.) – A Review

2020 ◽  
pp. 1-14
Author(s):  
Aswini Nunavath ◽  
Venkatraman Hegde ◽  
K. Gopala Krishna Murthy ◽  
V. Venkanna
Keyword(s):  
Molecular Markers ◽  
Fusarium Wilt ◽  
Abiotic Stresses ◽  
Ascochyta Blight ◽  
Molecular Techniques ◽  
Genetic Maps ◽  
Current Status ◽  
Yield Reduction ◽  
Biotic And Abiotic Stresses ◽  
Advanced Backcross

Chickpea is one of the most important pulse crops having estimated genome size of 738 Mb. The crop is affected by various biotic and abiotic stresses causing significant yield reduction. During the recent past, some biotic stresses like fusarium wilt, ascochyta blight, botrytis grey mould and abiotic stresses like drought, heat and salinity were found to reduce the productivity, thereafter, these demands for development of high yielding early maturing chickpea varieties with resistance to various biotic and abiotic stresses. Due to the advent of molecular techniques and availability of highly polymorphic and co-dominant microsatellite and other molecular markers, development of genetic maps for chickpea has progressed significantly. Molecular markers are now considered better than morphological and physiological characters for being stable, unaffected by environmental influences and easily detectable irrespective of their growth and development stages. The mapping of genes / QTLs for various traits like flowering time, yield and yield related traits, resistance to fusarium wilt, ascochyta blight, BGM, drought, salinity, heat may be useful in developing improved varieties of chickpea besides deeper understanding of genetics underlying the inheritance of the characters. The knowledge on mapped genes / QTLs for various traits of interest could help in integration of genomics-assisted breeding through various approaches like Marker Assisted Back Crossing, introgression of superior alleles from wild species through Advanced Backcross QTL, Marker Assisted Recurrent Selection and Genome Wide Selection for improving chickpea.

scholarly journals Marine nematode taxonomy in the age of DNA: the present and future of molecular tools to assess their biodiversity

Nematology ◽  
2010 ◽  
Vol 12 (5) ◽  
pp. 661-672 ◽  
Author(s):  
Neyvan Renato Rodrigues da Silva ◽  
Maria Cristina da Silva ◽  
Verônica Fonseca Genevois ◽  
André Morgado Esteves ◽  
Paul De Ley ◽  
...  
Keyword(s):  
Dna Barcoding ◽  
Processing Speed ◽  
Sequence Data ◽  
Molecular Taxonomy ◽  
Species Boundaries ◽  
Nominal Species ◽  
Marine Nematode ◽  
Molecular Tools ◽  
Variable Regions ◽  
Online Databases

Abstract Molecular taxonomy is one of the most promising yet challenging fields of biology. Molecular markers such as nuclear and mitochondrial genes are being used in a variety of studies surveying marine nematode taxa. Sequences from more than 600 species have been deposited to date in online databases. These barcode sequences are assigned to 150 nominal species from 104 genera. There are 41 species assigned to Enoplea and 109 species to Chromadorea. Morphology-based surveys are greatly limited by processing speed, while barcoding approaches for nematodes are hampered by difficulties in matching sequence data with morphology-based taxonomy. DNA barcoding is a promising approach because some genes contain variable regions that are useful to discriminate species boundaries, discover cryptic species, quantify biodiversity and analyse phylogeny. We advocate a combination of several approaches in studies of molecular taxonomy, DNA barcoding and conventional taxonomy as a necessary step to enhance the knowledge of biodiversity of marine nematodes.

scholarly journals The Nominal Species of the Bee Genus Centris Described by Johan Christian Fabricius (Hymenoptera: Apidae)

Sociobiology ◽  
2020 ◽  
Vol 67 (3) ◽  
pp. 401
Author(s):  
Felipe Vivallo
Keyword(s):  
Morphological Characteristics ◽  
Current Status ◽  
Nominal Species

In this paper the primary types of Centris bees described by the Danish entomologist Johan Christian Fabricius were studied. The primary types of C. flavifrons, C. analis, C. furcata, C. haemorrhoidalis, C. lanipes, C. longimana, C. similis, C. tabaniformis,  and  C. versicolor were analyzed, providing notes on their current status and depository. In addition, some photographs of selected species as well as morphological characteristics to recognize all Fabricius’ Centris bees are also provided.

scholarly journals Trypanosomatids (Protozoa: Kinetoplastida) in three species of Armored Catfish from Mogi-Guaçu river, Pirassununga, São Paulo, Brazil

2016 ◽  
Vol 25 (2) ◽  
pp. 131-141 ◽  
Author(s):  
Julia Pereira Molina ◽  
Rubens Riscala Madi ◽  
Vera Nisaka Solferini ◽  
Paulo Sérgio Ceccarelli ◽  
Hildete Prisco Pinheiro ◽  
...  
Keyword(s):  
Morphological Characteristics ◽  
Sao Paulo ◽  
Average Density ◽  
Molecular Techniques ◽  
Morphological Data ◽  
São Paulo ◽  
Significant Difference ◽  
General Average ◽  
Monthly Variations ◽  
Formation Of Groups

Abstract Trypanosome infections have been reported in several species of fish, in majority of cases described on the basis of morphological characteristics. Trypanosomes in fish are heteroxenous and transmitted by hirudineans. This study aims to evaluate the prevalence and density of infections by Trypanosoma sp. in blood from three species of catfish, Hypostomus regani, H. strigaticeps, H. albopunctatus, from the Mogi Guaçu River, Pirassununga, São Paulo, Brazil. Further, this study intends to characterize the Trypanosoma specimens found in the blood of these fish by morphological and molecular techniques. The trypanosomes overall prevalence observed was 47.6% with a general average density of 0.75 parasites/µl of blood. Hypostomus regani and Hypostomus strigaticeps showed a significant difference in prevalence. The average densities of parasites were not significantly different among the three fish species. Similar findings were observed for the monthly variations in densities. The parasites found in the three species of catfish studied showed similar morphological characteristics. The morphological data and the statistical analyses used in this study didn’t show the formation of groups. The analyses provided evidence of the presence of pleomorphisms in the trypanosomes found in the three studied fish.

scholarly journals Bioinformatics Approach to Mitigate Mislabeling in EU Seafood Market and Protect Consumer Health

2021 ◽  
Vol 18 (14) ◽  
pp. 7497
Author(s):  
Gabriella Vindigni ◽  
Alfredo Pulvirenti ◽  
Salvatore Alaimo ◽  
Clara Monaco ◽  
Daniela Spina ◽  
...  
Keyword(s):  
Dna Barcoding ◽  
Value Chain ◽  
Morphological Characteristics ◽  
Molecular Techniques ◽  
Consumer Information ◽  
Fish Market ◽  
Fishery Policy ◽  
Fisheries Policy ◽  
Consumer Interests ◽  
Zoonotic Parasites

Fisheries products are some of the most traded commodities world-wide and the potential for fraud is a serious concern. Fish fraud represents a threat to human health and poses serious concerns due to the consumption of toxins, highly allergenic species, contaminates or zoonotic parasites, which may be present in substituted fish. The substitution of more expensive fish by cheaper species, with similar morphological characteristics but different origins, reflects the need for greater transparency and traceability upon which which the security of the entire seafood value-chain depends. Even though EU regulations have made significant progress in consumer information by stringent labelling requirements, fraud is still widespread. Many molecular techniques such as DNA barcoding provide valuable support to enhance the Common Fisheries Policy (CFP) in the protection of consumer interests by unequivocally detecting any kind of fraud. This paper aims to highlight both the engagement of EU fishery policy and the opportunity offered by new biotechnology instruments to mitigate the growing fraud in the globalized fish market and to enforce the food security system to protect consumers’ health. In this paper, after a presentation of EU rules on fish labeling and a general overview on the current state of the global fish market, we discuss the public health implications and the opportunities offered by several techniques based on genetics, reporting a case study to show the efficacy of the DNA barcoding methodology in assessing fish traceability and identification, comparing different species of the Epinephelus genus, Mottled Grouper (Mycteroperca rubra) and Wreckfish (Polyprion americanus), often improperly sold with the commercial name of “grouper”.

Molecular markers and antioxidant activity in berry crops: Genetic diversity analysis

2012 ◽  
Vol 92 (6) ◽  
pp. 1121-1133 ◽  
Author(s):  
S. C. Debnath ◽  
Y. L. Siow ◽  
J. Petkau ◽  
D. An ◽  
N. V. Bykova
Keyword(s):  
Genetic Diversity ◽  
Antioxidant Activity ◽  
Molecular Markers ◽  
Molecular Techniques ◽  
Diversity Analysis ◽  
Full Potential ◽  
Genetic Diversity Analysis ◽  
Wide Range ◽  
Berry Crops ◽  
Improvement Programs

Debnath, S. C., Siow, Y. L., Petkau, J., An, D. and Bykova, N. V. 2012. Molecular markers and antioxidant activity in berry crops: Genetic diversity analysis. Can. J. Plant Sci. 92: 1121–1133. An improved understanding of important roles of dietary fruits in maintaining human health has led to a dramatic increase of global berry crop production. Berry fruits contain relatively high levels of vitamin C, cellulose and pectin, and produce anthocyanins, which have important therapeutic values, including antitumor, antiulcer, antioxidant and anti-inflammatory activities. There is a need to develop reliable methods to identify berry germplasm and assess genetic diversity/relatedness for dietary properties in berry genotypes for practical breeding purposes through genotype selection in a breeding program for cultivar development, and proprietary-rights protection. The introduction of molecular biology techniques, such as DNA-based markers, allows direct comparison of different genetic materials independent of environmental influences. Significant progress has been made in diversity analysis of wild cranberry, lowbush blueberry, lingonberry and cloudberry germplasm, and in strawberry and raspberry cultivars and advanced breeding lines developed in Canada. Inter simple sequence repeat (ISSR) markers detected an adequate degree of polymorphism to differentiate among berry genotypes, making this technology valuable for cultivar identification and for the more efficient choice of parents in the current berry improvement programs. Although multiple factors affect antioxidant activity, a wide range of genetic diversity has been reported in wild and cultivated berry crops. Diversity analysis based on molecular markers did not agree with those from antioxidant activity. The paper also discusses the issues that still need to be addressed to utilize the full potential of molecular techniques including expressed sequence tag-polymerase chain reaction (EST-PCR) analysis to develop improved environment-friendly berry cultivars suited to the changing needs of growers and consumers.

scholarly journals A GATA6-centred gene regulatory network involving HNFs and ΔNp63 controls plasticity and immune escape in pancreatic cancer

Gut ◽  
2021 ◽  
pp. gutjnl-2020-321397
Author(s):  
Bernhard Kloesch ◽  
Vivien Ionasz ◽  
Sumit Paliwal ◽  
Natascha Hruschka ◽  
Jaime Martinez de Villarreal ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
Immune Escape ◽  
Lung Metastases ◽  
Personalised Medicine ◽  
Molecular Taxonomy ◽  
Classification Systems ◽  
Ductal Adenocarcinoma ◽  
Tissue Samples ◽  
Basal Phenotype ◽  
Phenotype Switch

ObjectiveMolecular taxonomy of tumours is the foundation of personalised medicine and is becoming of paramount importance for therapeutic purposes. Four transcriptomics-based classification systems of pancreatic ductal adenocarcinoma (PDAC) exist, which consistently identified a subtype of highly aggressive PDACs with basal-like features, including ΔNp63 expression and loss of the epithelial master regulator GATA6. We investigated the precise molecular events driving PDAC progression and the emergence of the basal programme.DesignWe combined the analysis of patient-derived transcriptomics datasets and tissue samples with mechanistic experiments using a novel dual-recombinase mouse model for Gata6 deletion at late stages of KRasG12D-driven pancreatic tumorigenesis (Gata6LateKO).ResultsThis comprehensive human-to-mouse approach showed that GATA6 loss is necessary, but not sufficient, for the expression of ΔNp63 and the basal programme in patients and in mice. The concomitant loss of HNF1A and HNF4A, likely through epigenetic silencing, is required for the full phenotype switch. Moreover, Gata6 deletion in mice dramatically increased the metastatic rate, with a propensity for lung metastases. Through RNA-Seq analysis of primary cells isolated from mouse tumours, we show that Gata6 inhibits tumour cell plasticity and immune evasion, consistent with patient-derived data, suggesting that GATA6 works as a barrier for acquiring the fully developed basal and metastatic phenotype.ConclusionsOur work provides both a mechanistic molecular link between the basal phenotype and metastasis and a valuable preclinical tool to investigate the most aggressive subtype of PDAC. These data, therefore, are important for understanding the pathobiological features underlying the heterogeneity of pancreatic cancer in both mice and human.

A polyphasic approach to characterise two novel species of Phoma (Didymellaceae) from China

Phytotaxa ◽  
2015 ◽  
Vol 197 (4) ◽  
pp. 267-281 ◽  
Author(s):  
Qian Chen ◽  
KE ZHANG ◽  
GUOZHEN ZHANG ◽  
LEI CAI
Keyword(s):  
Rna Polymerase Ii ◽  
Internal Transcribed Spacer ◽  
Novel Species ◽  
Large Subunit ◽  
Morphological Characteristics ◽  
Polyphasic Approach ◽  
Nrdna Its ◽  
Two New Species ◽  
Viburnum Odoratissimum ◽  
Β Tubulin

Phoma odoratissimi sp. nov. on Viburnum odoratissimum and Syringa oblate, and Phoma segeticola sp. nov. on Cirsium segetum from China are introduced and described, employing a polyphasic approach characterising morphological characteristics, host association and phylogeny. Both species are the first records of Phoma species on their respective hosts. Multi-locus phylogenetic tree was inferred using combined sequences of the internal transcribed spacer regions 1 & 2 and 5.8S nrDNA (ITS), and partial large subunit 28S nrDNA region (LSU), β-tubulin (TUB) region and RNA polymerase II (RPB2) region. The two new species clustered in two separate and distinct lineages, and are distinct from their allied species.

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