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1.
Parasitol Int ; 96: 102771, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37302639

RESUMEN

Human diphyllobothriasis, caused by Dibothriocephalus nihonkaiensis, is prevalent globally, especially in regions where raw fish is consumed. Recent molecular diagnostic techniques have made species identification of tapeworm parasites and the determination of genetic variations among parasite populations possible. However, only a few studies done over a decade ago, have reported on the genetic variation among D. nihonkaiensis in Japan. The present study employed PCR-based mitochondrial DNA analysis to specifically detect D. nihonkaiensis from archived clinical samples, and to determine any genetic variation that may exist among the Japanese broad tapeworms from patients of Kanagawa Prefecture, Japan. Target genes were amplified from DNA extracted from the ethanol- or formaldehyde-fixed samples by PCR. Further sequencing and comparative phylogenetic analyses based on mitochondrial COI and ND1 sequences were also performed. In our results, all PCR-amplified and sequenced samples were identified as D. nihonkaiensis. Analysis of COI sequences revealed two haplotype lineages. However, clustering of almost all COI (and ND1) sample sequences into one of the two haplotype clades, together with reference sequences from different countries worldwide, revealed a common haplotype among D. nihonkaiensis samples in our study. Our results suggest a possible presence of a dominant D. nihonkaiensis haplotype, with a global distribution circulating in Japan. Results from this study have the potential to improve the management of clinical cases and establish robust control measures to reduce the burden of human diphyllobothriasis in Japan.


Asunto(s)
Cestodos , Infecciones por Cestodos , Difilobotriosis , Diphyllobothrium , Animales , Humanos , Haplotipos , Filogenia , Japón , Diphyllobothrium/genética , Cestodos/genética , Infecciones por Cestodos/veterinaria , Difilobotriosis/diagnóstico , Difilobotriosis/parasitología , Variación Genética
2.
Genes Dis ; 9(6): 1742-1756, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36157492

RESUMEN

All-trans retinoic acid (ATRA) can reverse the malignant behaviors of hepatocellular carcinoma (HCC) cells, thereby exerting anti-HCC effect; however, the underlying mechanism is yet to be understood. This study aimed to demonstrate that ATRA is vital to ferroptosis in HCC. Ferroptosis-related genes exhibit different expression in patients with HCC compared to that in healthy individuals. A total of 20 amino acid products were detected in HepG2 cells, the expression level of 5 was decreased after ATRA treatment. ATRA improved the levels of lipid ROS, MDA, and NAPD+/NADPH, and reduced the mt-DNA copy number and changed the structure of mitochondria, in HepG2 and Hep3B cells. We found the expression of genes positively correlated with ferroptosis to increase and those negatively correlated to decrease with ATRA treatment. Inhibition of ferroptosis by Ferrostatin-1 reversed ATRA-inhibited proliferation of HCC cells, along with cell migration and invasion. GSH synthesis was blocked by ATRA, accompanied by decreased cystine content and increased glutamate content, and downregulation of the expression of GSH synthesis-related genes. Our findings suggested that ATRA inhibited the malignancy of HCC cells by improving ferroptosis, and that inhibition of GSH synthesis contributed to ATRA-induced ferroptosis.

3.
Mol Med Rep ; 25(6)2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35425997

RESUMEN

Acute myeloid leukemia (AML) is a type of hematological malignancy caused by uncontrolled clonal proliferation of hematopoietic stem cells. The special energy metabolism mode of AML relying on oxidative phosphorylation is different from the traditional 'Warburg effect'. However, its mechanism is not clear. In the present study, it was demonstrated that the mRNA expression levels of NADH dehydrogenase subunit 1, 4 and 5 (ND1, ND4 and ND5) were upregulated in AML samples from The Cancer Genome Atlas database using the limma package in the R programming language. Reverse transcription­quantitative PCR and ELISA were used to verify the upregulation of ND1, ND4 and ND5 in clinical samples. Pan­cancer analysis revealed that the expression of ND1 was upregulated only in AML, ND2 was upregulated only in AML and thymoma, and ND4 was upregulated only in AML and kidney chromophobe. In the present study, it was demonstrated that silencing of ND1/4/5 could inhibit the proliferation of AML cells in transplanted tumor of nude mice. Additionally, it was found that oxidative phosphorylation and energy metabolism of AML cells were decreased after silencing of ND1/4/5. In conclusion, the present study suggested that ND1/4/5 may be involved in the regulation of oxidative phosphorylation metabolism in AML as a potential cancer­promoting factor.


Asunto(s)
Leucemia Mieloide Aguda , Fosforilación Oxidativa , Animales , Leucemia Mieloide Aguda/metabolismo , Ratones , Ratones Desnudos , NADH Deshidrogenasa/genética , NADH Deshidrogenasa/metabolismo , Regulación hacia Arriba
4.
Vet Res Forum ; 11(3): 265-271, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33133464

RESUMEN

Over the last decade, diagnostic tools to detect and differentiate Fasciola species have improved, but our understanding of the distribution of haplotypes and population structure of this parasite is less clear. This study was designed to survey this gap in the F. gigantica epidemiology in Kermanshah province, western Iran from 2015 to 2017. Sixty-eight Fasciola isolates were collected from slaughterhouses from this province. We evaluated the PCR-RFLP assay of the ITS1 genes for the identification of Fasciola species using the RsaI enzyme. After Fasciola species identification, the partial sequence of mitochondrial NADH dehydrogenase subunit 1 (ND1) gene of F. gigantica was used for subsequent construction of the phylogenetic tree and network analysis. Based on the PCR-PRFLP profile, one (6.25%) of sheep isolates and 19 (39.60%) of cattle isolates were detected as F. gigantica, whereas 93.75% of sheep isolates, 60.40% of cattle isolates and all of the goat isolates were F. hepatica. In the 20 analyzed flukes, five ND1 haplotypes were detected. Statistically significant genetic differentiation was demonstrated between the Iran population and all the other populations. Evidence is presented for the existence of two well-separated populations: African and West Asian gigantica flukes and East Asian gigantica flukes. Genetic relationships among haplotypes were associated with geographical divisions. Also, our results have heightened our knowledge about the genetic diversity of F. gigantic, providing the first evidence for the existence of two well-separated populations of this parasite.

5.
Trop Anim Health Prod ; 52(1): 331-337, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31338730

RESUMEN

Echinococcus granulosus sensu lato (s.l.) is the causative agent of cystic echinococcosis (CE) in animals and humans with a worldwide distribution affecting pastoral and agro-pastoral communities. Little is known about the genetic diversity and public health significance of E. granulosus s.l. among animals and human in Oman. This study was undertaken to investigate the circulating genotypes of E. granulosus s.l. in farm animals (camels, cattle, goats and sheep) by using multiplex PCR (mPCR) and sequence analysis of a fragment of the NADH dehydrogenase subunit 1 (NADH-1) gene. In this study, 39 hydatid cyst isolates from dromedary camels (n = 17), cattle (n = 12), goats (n = 9) and sheep (n = 1) from five governorates in Oman were collected. These isolates were analysed genetically to classify E. granulosus s.l. using a single-tube mPCR and further subjected to sequence analysis of mitochondrial NADH-1 gene. The results of mPCR revealed that most of the cyst isolates (71.8%) belonged to E. granulosus sensu stricto G1/G2/G3 genotypes, whereas 28.2% were linked to E. canadensis G6/G7 genotypes. However, sequencing of these isolates has confirmed the existence of the two genotypes E. canadensis G6 and E. granulosus sensu stricto G1 genotype. This study provides a molecular evidence of E. granulosus s.l. genotypes in Oman and confirms the predominance of the sheep and camel strains and their role in the transmission dynamics of CE in animals. The study will serve as a foundation for future planning and implementation for CE control program in Oman.


Asunto(s)
Equinococosis/veterinaria , Echinococcus granulosus/genética , Animales , Animales Domésticos , Camelus , Bovinos , Echinococcus , Echinococcus granulosus/aislamiento & purificación , Genotipo , Cabras , Humanos , Omán , Ovinos , Encuestas y Cuestionarios
6.
Acta Trop ; 204: 105304, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31857082

RESUMEN

Four species of echinostomes, Echinostoma revolutum (Froelich, 1802), Echinostoma ilocanum (Garrison, 1908), Hypoderaeum conoideum (Bloch, 1872) Dietz, 1909, and Artyfechinostomum malayanum (Leiper, 1911) Mendheim, 1943 commonly infect humans in Thailand, but their eggs present similar morphologies resulting in difficult differentiation for diagnosis. Present molecular methods have a great potential to provide superior detection/diagnosis. DNA sequences, especially the mitochondrial NADH dehydrogenase subunit 1 (ND1) gene, have already been used to differentiate among echinostomes; thus, we aimed to develop species-specific primers for the differential detection of four medically important echinostomes by multiplex PCR. The species-specific reverse primers and a forward primer were based on variable regions and conserved regions of the ND1 gene, respectively. Four reverse primers and a forward primer were combined in a multiplex PCR reaction to amplify the ND1 fragment. Different ND1 fragment sizes were amplified: 108, 209, 384 and 419 bp of E. revolutum H. conoideum, E. ilocanum and A. malayanum, respectively. Specificity was tested with other medically important parasite DNA; no cross-reaction occurred. Sensitivity ranged between 0.1 and 0.05 ng. The species-specific primers developed in this study could be of further use in differential diagnosis for these medically important echinostomes infection in human and animal hosts.


Asunto(s)
ADN de Helmintos/genética , Echinostomatidae/genética , Echinostomatidae/aislamiento & purificación , Reacción en Cadena de la Polimerasa Multiplex/métodos , Animales , Secuencia de Bases , Cartilla de ADN , Humanos , Tailandia
7.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-846728

RESUMEN

Objective: To explore genetic variations of Hypoderaeum conoideum collected from domestic ducks from 12 different localities in Thailand and Lao PDR, as well as their phylogenetic relationship with American and European isolates. Methods: The nucleotide sequences of their nuclear ribosomal DNA (ITS), mitochondrial cytochrome c oxidase subunit 1 (CO1), and NADH dehydrogenase subunit 1 (ND1) were used to analyze genetic diversity indices. Results: We found relatively high levels of nucleotide polymorphism in ND1 (4.02%), whereas moderate and low levels were observed in CO1 (2.11%) and ITS (0.96%), respectively. Based on these polymorphisms, the 20 ND1, 12 CO1, and 18 ITS haplotypes were classified, and several common haplotypes were observed in all samples. At least three major lineages, namely American, European and Asian lineages, have been classified by phylogenetic analyses based on ND1 sequences. Conclusions: Our report demonstrates that the ND1 gene is the most suitable genetic marker to explore genetic variation and phylogenetic relationship of Hypoderaeum conoideum. However, a combination of all loci for ND1, CO1 and ITS would be of great value toward further genetic investigation of this endemic worldwide parasite. Thus, comprehensive molecular genetic analyses of Hypoderaeum conoideum from its worldwide distribution is needed to further understanding of the evolutionary and systematic relationships of this parasite.

8.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-951133

RESUMEN

Objective: To explore genetic variations of Hypoderaeum conoideum collected from domestic ducks from 12 different localities in Thailand and Lao PDR, as well as their phylogenetic relationship with American and European isolates. Methods: The nucleotide sequences of their nuclear ribosomal DNA (ITS), mitochondrial cytochrome c oxidase subunit 1 (CO1), and NADH dehydrogenase subunit 1 (ND1) were used to analyze genetic diversity indices. Results: We found relatively high levels of nucleotide polymorphism in ND1 (4.02%), whereas moderate and low levels were observed in CO1 (2.11%) and ITS (0.96%), respectively. Based on these polymorphisms, the 20 ND1, 12 CO1, and 18 ITS haplotypes were classified, and several common haplotypes were observed in all samples. At least three major lineages, namely American, European and Asian lineages, have been classified by phylogenetic analyses based on ND1 sequences. Conclusions: Our report demonstrates that the ND1 gene is the most suitable genetic marker to explore genetic variation and phylogenetic relationship of Hypoderaeum conoideum. However, a combination of all loci for ND1, CO1 and ITS would be of great value toward further genetic investigation of this endemic worldwide parasite. Thus, comprehensive molecular genetic analyses of Hypoderaeum conoideum from its worldwide distribution is needed to further understanding of the evolutionary and systematic relationships of this parasite.

9.
Genes (Basel) ; 10(12)2019 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-31810328

RESUMEN

Renal cell carcinoma (RCC) is associated with various genetic alterations. Although whole-genome/exome sequencing analysis has revealed that nuclear genome alterations are associated with clinical outcomes, the association between nucleotide alterations in the mitochondrial genome and RCC clinical outcomes remains unclear. In this study, we analyzed somatic mutations in the mitochondrial D-loop region, using RCC samples from 61 consecutive patients with localized RCC. Moreover, we analyzed the relationship between D-loop mutations and NADH dehydrogenase subunit 1 (MT-ND1) mutations, which we previously found to be associated with clinical outcomes in localized RCC. Among the 61 localized RCCs, 34 patients (55.7%) had at least one mitochondrial D-loop mutation. The number of D-loop mutations was associated with larger tumor diameter (> 32 mm) and higher nuclear grade (≥ ISUP grade 3). Moreover, patients with D-loop mutations showed no differences in cancer-specific survival when compared with patients without D-loop mutations. However, the co-occurrence of D-loop and MT-ND1 mutations improved the predictive accuracy of cancer-related deaths among our cohort, increasing the concordance index (C-index) from 0.757 to 0.810. Thus, we found that D-loop mutations are associated with adverse pathological features in localized RCC and may improve predictive accuracy for cancer-specific deaths when combined with MT-ND1 mutations.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Mutación , NADH Deshidrogenasa/genética , Proteínas de Neoplasias/genética , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Renales/enzimología , Carcinoma de Células Renales/genética , Carcinoma de Células Renales/mortalidad , Supervivencia sin Enfermedad , Femenino , Humanos , Neoplasias Renales/enzimología , Neoplasias Renales/genética , Neoplasias Renales/mortalidad , Masculino , Persona de Mediana Edad , NADH Deshidrogenasa/metabolismo , Proteínas de Neoplasias/metabolismo , Valor Predictivo de las Pruebas , Tasa de Supervivencia
10.
Vet Parasitol ; 273: 45-51, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31442892

RESUMEN

Fasciola gigantica and hybrid Fasciola are distributed throughout Asia. Herein, we investigated the species of the Fasciola fluke distributed in three hotspots of fascioliasis in Cambodia. A total of 92 flukes collected from 21 slaughtered cattle from Kandal (44), Battambang (41), and Kratie (7) Provinces were identified as F. gigantica using multiplex PCR for a nuclear phosphoenolpyruvate carboxykinase (PEPCK) gene. The overall prevalence of F. gigantica infestation was 7.14% (21/294). Phylogenetic as well as population genetics analyses were performed using the mitochondrial NADH dehydrogenase subunit 1 (ND1). The 19 ND1 haplotypes were identified from Cambodian F. gigantica (haplotype diversity, 0.83). All of the haplotypes were classified into F. gigantica haplogroup C, which includes ND1 haplotypes detected from Thailand, Vietnam, Indonesia, Myanmar, and China. Among haplogroup C, novel and unique haplotypes of Cambodia were found in the Battambang and Kandal Provinces, and the nucleotide diversity of the Cambodian population (0.00532) was the highest. Pairwise fixation indices among the F. gigantica populations from these countries indicated that the Cambodian and Thailand populations were related to each other. The highest genetic diversity in the Cambodian population suggests that F. gigantica in Cambodia may be the ancestor of the populations in Southeast Asian countries. Most likely, livestock movement, including Zebu cattle, played an important role in the transmission of F. gigantica. In this study, the hybrid Fasciola flukes that are commonly found in neighboring countries, were not found in Cambodia. Further comprehensive investigations of Fasciola prevalence should be conducted by analyzing a wider range of hosts throughout Cambodia to reach a more solid conclusion about the absence of hybrid flukes.


Asunto(s)
Distribución Animal , Enfermedades de los Bovinos/parasitología , Fasciola/clasificación , Fasciola/genética , Fascioliasis/veterinaria , Variación Genética , Animales , Asia Sudoriental/epidemiología , Cambodia , Bovinos , Enfermedades de los Bovinos/epidemiología , Fascioliasis/epidemiología , Fascioliasis/parasitología , Haplotipos , NADH Deshidrogenasa/genética , Fosfotransferasas/genética , Prevalencia
11.
Cell Cycle ; 14(1): 86-98, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25483072

RESUMEN

Cancer stem cells (CSCs) represent a subpopulation of tumor cells endowed with self-renewal capacity and are considered as an underlying cause of tumor recurrence and metastasis. The metabolic signatures of CSCs and the mechanisms involved in the regulation of their stem cell-like properties still remain elusive. We utilized nasopharyngeal carcinoma (NPC) CSCs as a model to dissect their metabolic signatures and found that CSCs underwent metabolic shift and mitochondrial resetting distinguished from their differentiated counterparts. In metabolic shift, CSCs showed a greater reliance on glycolysis for energy supply compared with the parental cells. In mitochondrial resetting, the quantity and function of mitochondria of CSCs were modulated by the biogenesis of the organelles, and the round-shaped mitochondria were distributed in a peri-nuclear manner similar to those seen in the stem cells. In addition, we blocked the glycolytic pathway, increased the ROS levels, and depolarized mitochondrial membranes of CSCs, respectively, and examined the effects of these metabolic factors on CSC properties. Intriguingly, the properties of CSCs were curbed when we redirected the quintessential metabolic reprogramming, which indicates that the plasticity of energy metabolism regulated the balance between acquisition and loss of the stemness status. Taken together, we suggest that metabolic reprogramming is critical for CSCs to sustain self-renewal, deter from differentiation and enhance the antioxidant defense mechanism. Characterization of metabolic reprogramming governing CSC properties is paramount to the design of novel therapeutic strategies through metabolic intervention of CSCs.


Asunto(s)
Metabolismo Energético , Mitocondrias/metabolismo , Células Madre Neoplásicas/metabolismo , Antioxidantes/metabolismo , Diferenciación Celular , Línea Celular Tumoral , Transportador de Glucosa de Tipo 1/metabolismo , Glucólisis , Hexoquinasa/metabolismo , Humanos , Potencial de la Membrana Mitocondrial , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/patología , Proteínas Serina-Treonina Quinasas/metabolismo , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora , Especies Reactivas de Oxígeno/metabolismo , Factores de Transcripción/metabolismo
12.
Int J Parasitol Parasites Wildl ; 3(2): 81-7, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25161905

RESUMEN

Echinococcus multilocularis is a zoonotic cestode with a distribution encompassing the northern hemisphere that causes alveolar hydatid disease in people and other aberrant hosts. E. multilocularis is not genetically uniform across its distribution, which may have implications for zoonotic transmission and pathogenicity. Recent findings of a European-type haplotype of E. multilocularis in wildlife in one location in western Canada motivated a broader survey of the diversity of this parasite in wildlife from northern and western Canada. We obtained intact adult cestodes of E. multilocularis from the intestines of 41 wild canids (wolf - Canis lupus, coyote - Canis latrans, and red fox - Vulpes vulpes), taeniid eggs from 28 fecal samples from Arctic fox (Vulpes lagopus), and alveolar hydatid cysts from 39 potential rodent intermediate hosts. Upon sequencing a 370-nucelotide region of the NADH dehydrogenase subunit 1 (nad1) mitochondrial locus, 17 new haplotypes were identified. This constitutes a much higher diversity than expected, as only two genotypes (European and an Asian/North American) had previously been identified using this locus. The European-type strain, recently introduced, may be widespread in wildlife within western Canada, possibly related to the large home ranges and wide dispersal range of wild canids. This study increased understanding of the biogeographic distribution, prevalence and genetic differences of a globally important pathogenic cestode in northern and western Canada.

13.
Gene ; 533(1): 356-65, 2014 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-23954873

RESUMEN

The complete 15,223-bp mitochondrial genome (mitogenome) of Tryporyza incertulas (Walker) (Lepidoptera: Pyraloidea: Crambidae) was determined, characterized and compared with seven other species of superfamily Pyraloidea. The order of 37 genes was typical of insect mitochondrial DNA sequences described to date. Compared with other moths of Pyraloidea, the A+T biased (77.0%) of T. incertulas was the lowest. Eleven protein-coding genes (PCGs) utilized the standard ATN, but cox1 used CGA and nad4 used AAT as the initiation codons. Ten protein-coding genes had the common stop codon TAA, except nad3 having TAG as the stop codon, and cox2, nad4 using T, TA as the incomplete stop codons, respectively. All of the tRNA genes had typical cloverleaf secondary structures except trnS1(AGN), in which the dihydrouridine (DHU) arm did not form a stable stem-loop structure. There was a spacer between trnQ and nad2, which was common in Lepidoptera moths. A 6-bp motif 'ATACTA' between trnS2(UCN) and nad1, a 7-bp motif "AGC(T)CTTA" between trnW and trnC and a 6-bp motif "ATGATA" of overlapping region between atp8 and atp6 were found in Pyraloidea moths. The A+T-rich region contained an 'ATAGT(A)'-like motif followed by a poly-T stretch. In addition, two potential stem-loop structures, a duplicated 19-bp repeat element, and two microsatellites '(TA)12' and '(TA)9' were observed in the A+T-rich region of T. incertulas mitogenome. Finally, the phylogenetic relationships of Pyraloidea species were constructed based on amino acid sequences of 13 PCGs of mitogenomes using Bayesian inference (BI) and maximum likelihood (ML) methods. These molecular-based phylogenies supported the morphological classification on relationships within Pyraloidea species.


Asunto(s)
Genoma Mitocondrial , Mariposas Nocturnas/genética , Animales , Secuencia de Bases , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa , ARN Ribosómico/genética , ARN de Transferencia/genética , Homología de Secuencia de Ácido Nucleico
14.
Gene ; 533(1): 439-46, 2014 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-24084366

RESUMEN

In contrast to the extreme conservation of nuclear-encoded tRNAs, organization of the mitochondrial (mt) tRNA gene family in invertebrates is highly dynamic and rapidly evolving. While gene duplication and loss, gene isomerism, recruitment, and rearrangements have occurred sporadically in several invertebrate lineages, little is known regarding the pattern of their evolution. Comparisons of invertebrate mt genomes at a generic level can be extremely helpful in investigating evolutionary patterns of variation, as intermediate stages of the process may be identified. Variation of mitochondrial tRNA organization among Meretrix clams provides good materials to investigate mt tRNA evolution. We characterized the complete mt genome of the lyrate Asiatic hard clam Meretrix lyrata, re-annotated tRNAs of four previously sequenced Meretrix clams, and undertook an intensive comparison of tRNA gene families in these clams. Our results 1) provide evidence that the commonly observed duplication of trnM may have occurred independently in different bivalve lineages and, based on the higher degree of trnM gene similarity, may have occurred more recently than expected; 2) suggest that "horizontal" evolution may have played an important role in tRNA gene family evolution based on frequent gene duplications and gene recruitment events; and 3) reveal the first case of isoacceptor "vertical" tRNA gene recruitment (VTGR) and present the first clear evidence that VTGR allows rapid evolution of tRNAs. We identify the trnS(-UCR) gene in Meretrix clams, previously considered missing in this lineage, and speculate that trnS(-UCR) lacking the D-arm in both M. lyrata and Meretrix lamarckii may represent the ancestral status. Phylogenetic analysis based on 13 concatenate protein-coding genes provided opportunities to detect rapidly evolved tRNA genes via VTGR and gene isomerism processes. This study suggests that evolution of the mt tRNA gene family in bivalves is more complex than previously thought and that comparison of several congeneric species is a useful strategy in investigating evolutionary patterns and dynamics of mt tRNA genes.


Asunto(s)
Bivalvos/genética , Genoma Mitocondrial , ARN de Transferencia/genética , Animales , Secuencia de Bases , ADN , Datos de Secuencia Molecular , Homología de Secuencia de Ácido Nucleico
15.
Gene ; 535(2): 336-44, 2014 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-24177232

RESUMEN

Three previously studied mitochondrial genomes of glass sponges (phylum Porifera, class Hexactinellida) contained single nucleotide insertions in protein coding genes inferred as sites of +1 translational frameshifting. To investigate the distribution and evolution of these sites and to help elucidate the mechanism of frameshifting, we determined eight new complete or nearly complete mtDNA sequences from glass sponges and examined individual mitochondrial genes from three others. We found nine new instances of single nucleotide insertions in these sequences and analyzed them both comparatively and phylogenetically. The base insertions appear to have been gained and lost repeatedly in hexactinellid mt protein genes, suggesting no functional significance for the frameshifting sites. A high degree of sequence conservation, the presence of unusual tRNAs, and a distinct pattern of codon usage suggest the "out-of-frame pairing" model of translational frameshifting. Additionally, we provide evidence that relaxed selection pressure on glass sponge mtDNA - possibly a result of their low growth rates and deep-water lifestyle - has allowed frameshift insertions to be tolerated for hundreds of millions of years. Our study provides the first example of a phylogenetically diverse and extensive usage of translational frameshifting in animal mitochondrial coding sequences.


Asunto(s)
ADN Mitocondrial/genética , Sistema de Lectura Ribosómico , Poríferos/genética , Secuencia de Aminoácidos , Animales , ADN Mitocondrial/metabolismo , Evolución Molecular , Mutación del Sistema de Lectura , Orden Génico , Genes Mitocondriales , Genoma Mitocondrial , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Filogenia , Poríferos/clasificación , Poríferos/metabolismo , ARN de Transferencia/genética , ARN de Transferencia/metabolismo , Selección Genética , Alineación de Secuencia
16.
Gene ; 529(1): 1-6, 2013 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-23954222

RESUMEN

Liriomyza trifolii (Burgess), Liriomyza huidobrensis (Blanchard), and Liriomyza bryoniae (Kaltenbach), are three closely related and economically important leafminer pests in the world. This study examined the complete mitochondrial genomes of L. trifolii, L. huidobrensis and L. bryoniae, which were 16,141 bp, 16,236 bp and 16,183 bp in length, respectively. All of them displayed 37 typical animal mitochondrial genes and an A+T-rich region. The genomes were highly compact with only 60-68 bp of non-coding intergenic spacer. However, considerable differences in the A+T-rich region were detected among the three species. Results of this study also showed the two ribosomal RNA genes of the three species had very limited variable sites and thus should not provide much information in the study of population genetics of these species. Data generated from three leafminers' complete mitochondrial genomes should provide valuable information in studying phylogeny of Diptera, and developing genetic markers for species identification in leafminers.


Asunto(s)
Dípteros/clasificación , Dípteros/genética , Genoma de los Insectos , Genoma Mitocondrial/genética , Filogenia , Animales , Cartilla de ADN , ADN Intergénico/genética , ADN Mitocondrial/genética , Orden Génico , Genes Mitocondriales , Genes de ARNr , Marcadores Genéticos , Datos de Secuencia Molecular , Conformación de Ácido Nucleico , ARN Ribosómico , Análisis de Secuencia de ADN
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