• Title/Summary/Keyword: sequence divergence

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Occurrence and Evolutionary Analysis of Coat Protein Gene Sequences of Iranian Isolates of Sugarcane mosaic virus

  • Moradi, Zohreh;Nazifi, Ehsan;Mehrvar, Mohsen
    • The Plant Pathology Journal
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    • v.33 no.3
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    • pp.296-306
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    • 2017
  • Sugarcane mosaic virus (SCMV) is one of the most damaging viruses infecting sugarcane, maize and some other graminaceous species around the world. To investigate the genetic diversity of SCMV in Iran, the coat protein (CP) gene sequences of 23 SCMV isolates from different hosts were determined. The nucleotide sequence identity among Iranian isolates was more than 96%. They shared nucleotide identities of 75.5-99.9% with those of other SCMV isolates available in GenBank, the highest with the Egyptian isolate EGY7-1 (97.5-99.9%). The results of phylogenetic analysis suggested five divergent evolutionary lineages that did not completely reflect the geographical origin or host plant of the isolates. Population genetic analysis revealed greater between-group than within-group evolutionary divergence values, further supporting the results of the phylogenetic analysis. Our results indicated that natural selection might have contributed to the evolution of isolates belonging to the five identified SCMV groups, with infrequent genetic exchanges occurring between them. Phylogenetic analyses and the estimation of genetic distance indicated that Iranian isolates have low genetic diversity. No recombination was found in the CP cistron of Iranian isolates and the CP gene was under negative selection. These findings provide a comprehensive analysis of the population structure and driving forces for the evolution of SCMV with implications for global exchange of sugarcane germplasm. Gene flow, selection and somehow homologous recombination were found to be the important evolutionary factors shaping the genetic structure of SCMV populations.

Molecular Cloning of Cytochrome P450 Family Gene Fragment from Midgut of the Beet Armyworm, Spodoptera exigua

  • Moon, Jae-Yu;Lee, Pyeongjae;Cho, Il-Je;Kim, Iksoo;Lee, Heui-Sam
    • International Journal of Industrial Entomology and Biomaterials
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    • v.4 no.2
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    • pp.155-162
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    • 2002
  • Cytochrome P45O (CYP) gene has been known to play one of the most important roles in metabolizing the exogenous materials. In insect, CYP is particularly known to detoxify toxic materials by adding oxygen molecule to the hydrophobic region of the materials. Thus, CYP-dependent metabolism is associated with the adaptation of insect to host plant chemicals. This in turn is known to be one of the driving forces for CYP diversification. In the present study, we cloned seven gene fragments of CYP 4 (CYP4) family from the midgut of the beet armyworm, Spodoptera exigua, through RT.PCT, Sequence analysis of the product showed the gene fragment to contain an open reading frame of ~150 amino acids, consisted of ~450 bp. The cloned gene fragments contained typical, conserved regions found in CYP4 family. Pairwise comparison of the deduced amino acid sequences among seven clones ranged in divergence from 0% to 52.86% and resulted in five distinct clones. The other two clones were identical or differ by one amino acid respectively to the corresponding clone, although each differed by ten nucleotides. Analysis of correlation between GenBank-registered, full length CYP4 and the cloned fragments resulted in statistically significant relationship ($r^{2}$ = 0.96085; p < 0.001), suggesting utility of the partial sequences as such full-length sequences. Phylogenetic analysis of the clones with GenBank-registered insect and mammal CYP4 family sequences by parsimony and several distance methods subdivided the clones into two groups: tones belonging to CYP4S and the others to CYP4M families.

Biocomputational Characterization and Evolutionary Analysis of Bubaline Dicer1 Enzyme

  • Singh, Jasdeep;Mukhopadhyay, Chandra Sekhar;Arora, Jaspreet Singh;Kaur, Simarjeet
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.6
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    • pp.876-887
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    • 2015
  • Dicer, an ribonuclease type III type endonuclease, is the key enzyme involved in biogenesis of microRNAs (miRNAs) and small interfering RNAs (siRNAs), and thus plays a critical role in RNA interference through post transcriptional regulation of gene expression. This enzyme has not been well studied in the Indian water buffalo, an important species known for disease resistance and high milk production. In this study, the primary coding sequence (5,778 bp) of bubaline dicer (GenBank: AB969677.1) was determined and the bubaline Dicer1 biocomputationally characterized to determine the phylogenetic signature among higher eukaryotes. The evolutionary tree revealed that all the transcript variants of Dicer1 belonging to a specific species were within the same node and the sequences belonging to primates, rodents and lagomorphs, avians and reptiles formed independent clusters. The bubaline dicer1 is closely related to that of cattle and other ruminants and significantly divergent from dicer of lower species such as tapeworm, sea urchin and fruit fly. Evolutionary divergence analysis conducted using MEGA6 software indicated that dicer has undergone purifying selection over the time. Seventeen divergent sequences, representing each of the families/taxa were selected to study the specific regions of positive vis-$\grave{a}$-vis negative selection using different models like single likelihood ancestor counting, fixed effects likelihood, and random effects likelihood of Datamonkey server. Comparative analysis of the domain structure revealed that Dicer1 is conserved across mammalian species while variation both in terms of length of Dicer enzyme and presence or absence of domain is evident in the lower organisms.

Determining the Specific Status of Korean Collared Scops Owls

  • Hong, Yoon Jee;Kim, Young Jun;Murata, Koichi;Lee, Hang;Min, Mi-Sook
    • Animal Systematics, Evolution and Diversity
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    • v.29 no.2
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    • pp.136-143
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    • 2013
  • The collared scops owl that occurs in Korea is a protected species but its exact specific status has been questioned. To resolve the species status, a molecular phylogenetic analysis was conducted using two fragments of mitochondrial DNA, cytochrome b (cyt b, 891 bp) and NADH dehydrogenase subunit 2 (ND2, 627 bp) genes. Phylogenetic trees of cyt b revealed that all Korean specimens formed a monophyletic group with Japanese scops owl Otus semitorques with very low sequence divergence (d=0.008). We obtained a similar ND2 tree as well (d=0.003); however, the genetic distance between Korean individuals and O. lempiji from GenBank (AJ004026-7, EU348987, and EU601036) was very high and sufficient enough to separate them as species (cyt b, d=0.118; ND2, d=0.113). We also found that Korean species showed high differentiation from O. bakkamoena (AJ004018-20 and EU601034; cyt b, d=0.106; ND2, d=0.113) and O. lettia (EU601109 and EU601033, cyt b, d=0.110; ND2, d=0.117) as well. Therefore, we suggest that the Korean collared scops owl should be designated as Otus semitorques.

Identification and Phylogenetic Analysis of the Human Endogenous Retrovirus HERV-W LTR Family in Placenta cDNA Library

  • Yi, Joo-Mi;Lee, Ji-Won;Shin, Kyung-Mi;Huh, Jae-Won;Lee, Won-Ho;Jang, Kyung-Lib;Kim, Heui-Soo
    • Animal cells and systems
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    • v.5 no.3
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    • pp.243-246
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    • 2001
  • Human endoqenous retroviral long terminal repeats (LTRs) have been found to be coexpressed with sequences of genes closely located nearby. It has been suggested that the LTR elements have contributed to structural changes or genetic variations of human genome connected to various diseases and evolution. Using cDNA library derived from placenta tissue, we performed PCR amplification and identified five new HERV-W LTR elements. Those LTR elements showed a high degree of sequence similarity (98-99%) with HERV-W LTR (AF072500). A phylogenetic tree obtained by the neighbor-joining method revealed that HERV-W LTR elements could be mainly divided into two groups through evolutionary divergence. Five new HERV-W LTR elements (pla-1, 4, 5, 6, 7) belonged to the group I with AX000960, AF072504, and AF072506 from GenBank database. The data suggest that several copy numbers of the HERV-W LTR elements are transcribed in placenta and may contribute to the understanding of biological function such as human placental morphogenesis.

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Assessment of genetic diversity of Prangos fedtschenkoi (Apiaceae) and its conservation status based on ISSR markers

  • Mustafina, Feruza U.;Kim, Eun Hye;Son, Sung-Won;Turginov, Orzimat T.;Chang, Kae Sun;Choi, Kyung
    • Korean Journal of Plant Taxonomy
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    • v.47 no.1
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    • pp.11-22
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    • 2017
  • Prangos fedtschenkoi (Regel et Schmalh.) Korovin (Apiaceae) is an endemic species for mountainous Middle Asia, which is both a rare and useful plant. Organic extractions from this species are being used in pharmaceutics and cosmetology. In recent years, P. fedtschenkoi distribution area has considerably decreased, presumably, resulting from human activities such as agriculture, construction works, overgrazing and collection from wild for pharmaceutic purposes. Six populations were found in Uzbekistan and their genetic divergence and differentiation were studied with 10 inter-simple sequence repeat (ISSR) markers, selected out of 101. Totally 166 amplified ISSR fragments (loci) were revealed, of which 164 were polymorphic. Relatively moderate level of polymorphism was found at population level with polymorphic bands ranging from 27.71% to 47.59%. Mean P = 39.05%, $N_a=1.40$, $N_e=1.25$, S.I. = 0.21, and $H_e=0.14$ were revealed for all loci across six populations. AMOVA showed higher variation among populations (62%) than within them (38%). The Bayesian model determined 5 clusters, or genetic groups. The posteriori distribution of the Theta II estimator detected full model identifying high inbreeding, intensified by low gene flow (Nm = 0.3954). Mantel test confined population 6 as distinct cluster corresponding to geographic remoteness (R = 0.5137, $p{\leq}0.005$). Results were used as the bases for developing conserve measures to restore populations.

Additional mitochondrial DNA sequences from the dung beetle, Copris tripartitus (Coleoptera: Scarabaeidae), an endangered species in South Korea

  • Hwang, Eun Ju;Jeong, Su Yeon;Wang, Ah Rha;Kim, Min Jee;Kim, Iksoo
    • International Journal of Industrial Entomology and Biomaterials
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    • v.36 no.2
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    • pp.31-41
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    • 2018
  • The dung beetle, Copris tripartitus (Coleoptera: Scarabaeidae), is an endangered insect in South Korea. Previously, partial mitochondrial COI and CytB gene sequences have been used to infer genetic diversity and gene flow of this species in South Korea. In this study, we additionally collected C. tripartitus (n = 35) from one previous locality and two new localities, sequenced COI and CytB genes, and combined these with preexisting data for population genetic analysis. Sequence divergence of current samples showed slightly lower values [4.86% (32 bp) for COI and 4.16% (18 bp) for CytB] than that in the previous study. Nucleotide diversity (${\pi}$) ranged from 0.005336 (Gulupdo) to 0.020756 (Seogwi-dong) in COI and 0.009060 (Aewol-eup) to 0.017464 (Seogwi-dong) in CytB. Seogwi-dong samples that showed the highest ${\pi}$ in the previous study also showed the highest ${\pi}$ in this study for both gene sequences. The newly investigated Gulupdo samples had the lowest haplotype diversity for both gene sequences. They also had the lowest ${\pi}$ for COI and the second lowest ${\pi}$ for CytB. On the other hand, the newly added Haean-dong sample had relatively higher diversity estimates. Gene flow among populations was high, although significant difference was only detected between Gulupdo and Anmado or between Gulupdo and Seogwi-dong for COI sequences (P < 0.05). Considering the high genetic diversity and gene flow in C. tripartitus populations, one major issue regarding conservation seems not to be recovery of genetic diversity.

Genetic Diversity of Taenia asiatica from Thailand and Other Geographical Locations as Revealed by Cytochrome c Oxidase Subunit 1 Sequences

  • Anantaphruti, Malinee Thairungroj;Thaenkham, Urusa;Watthanakulpanich, Dorn;Phuphisut, Orawan;Maipanich, Wanna;Yoonuan, Tippayarat;Nuamtanong, Supaporn;Pubampen, Somjit;Sanguankiat, Surapol
    • Parasites, Hosts and Diseases
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    • v.51 no.1
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    • pp.55-59
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    • 2013
  • Twelve 924 bp cytochrome c oxidase subunit 1 (cox1) mitochondrial DNA sequences from Taenia asiatica isolates from Thailand were aligned and compared with multiple sequence isolates from Thailand and 6 other countries from the GenBank database. The genetic divergence of T. asiatica was also compared with Taenia saginata database sequences from 6 different countries in Asia, including Thailand, and 3 countries from other continents. The results showed that there were minor genetic variations within T. asiatica species, while high intraspecies variation was found in T. saginata. There were only 2 haplotypes and 1 polymorphic site found in T. asiatica, but 8 haplotypes and 9 polymorphic sites in T.saginata. Haplotype diversity was very low, 0.067, in T. asiatica and high, 0.700, in T. saginata. The very low genetic diversity suggested that T. asiatica may be at a risk due to the loss of potential adaptive alleles, resulting in reduced viability and decreased responses to environmental changes, which may endanger the species.

Druggability for COVID-19: in silico discovery of potential drug compounds against nucleocapsid (N) protein of SARS-CoV-2

  • Ray, Manisha;Sarkar, Saurav;Rath, Surya Narayan
    • Genomics & Informatics
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    • v.18 no.4
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    • pp.43.1-43.13
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    • 2020
  • The coronavirus disease 2019 is a contagious disease and had caused havoc throughout the world by creating widespread mortality and morbidity. The unavailability of vaccines and proper antiviral drugs encourages the researchers to identify potential antiviral drugs to be used against the virus. The presence of RNA binding domain in the nucleocapsid (N) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) could be a potential drug target, which serves multiple critical functions during the viral life cycle, especially the viral replication. Since vaccine development might take some time, the identification of a drug compound targeting viral replication might offer a solution for treatment. The study analyzed the phylogenetic relationship of N protein sequence divergence with other 49 coronavirus species and also identified the conserved regions according to protein families through conserved domain search. Good structural binding affinities of a few natural and/or synthetic phytocompounds or drugs against N protein were determined using the molecular docking approaches. The analyzed compounds presented the higher numbers of hydrogen bonds of selected chemicals supporting the drug-ability of these compounds. Among them, the established antiviral drug glycyrrhizic acid and the phytochemical theaflavin can be considered as possible drug compounds against target N protein of SARS-CoV-2 as they showed lower binding affinities. The findings of this study might lead to the development of a drug for the SARS-CoV-2 mediated disease and offer solution to treatment of SARS-CoV-2 infection.

Population genetic analysis of Salurnis marginella (Hemiptera: Flatidae)

  • Choi, Hyun-Seok;Jeong, Su Yeon;Lee, Keon Hee;Jeong, Jun Seong;Park, Jeong Sun;Jeong, Na Ra;Kim, Min Jee;Lee, Wonhoon;Kim, Iksoo
    • International Journal of Industrial Entomology and Biomaterials
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    • v.43 no.2
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    • pp.67-77
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    • 2021
  • Salurnis marginella Guérin-Méneville, 1829 (Hemiptera: Flatidae) is an invasive species first reported in 2003 in Iksan, which is located in the mid-western region of South Korea, and subsequently found in the nearby regions in 2005. However, molecular-perspective reports on their invasive characteristics are not yet available. In this study, population genetic characteristics of Korean S. marginella were evaluated using the mitochondrial COI region and sequencing 124 individual samples collected in 11 Korean localities. A total of 12 haplotypes were identified with a maximum sequence divergence of 1.368% (9 bp). Haplotype diversity was relatively higher than that of other insect species invaded into Korea, providing 2-6 haplotypes per populations, indicating that introduction to Korea may have happened rather extensively and consistently. Nucleotide diversity (π) was the highest in Iksan but owing to the limited sample size (three individuals) from this locality, additional studies are required for drawing conclusive inference regarding the place of entry to Korea. Ulsan, the easternmost population in the present study, revealed nearly the lowest diversity estimates, such as the lowest H and the second-lowest π; a unique haplogroup with a higher frequency; and an independent genetic cluster, suggesting that the introduction of S. marginella to Ulsan was an independent event. Further collection in Korea and neighboring countries, including the original distributional range is necessary to elucidate the invasive dynamics of S. marginella