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1.
J Gene Med ; 26(2): e3663, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38342961

RESUMO

BACKGROUND: Previous studies have established a connection between Hashimoto's thyroiditis (HT) and an increased risk of papillary thyroid carcinoma (PTC). However, the molecular mechanisms driving this association are not well understood. The long non-coding RNA (lncRNA) BRAF-activated non-coding RNA (BANCR) has been implicated in various cancers, suggesting a potential role in the HT-PTC linkage. METHODS: This study investigated the expression levels of BANCR in PTC and HT samples, compared to control tissues. We also examined the association between BANCR expression and clinicopathological features, including lymph node metastasis. Furthermore, we explored the molecular mechanisms of BANCR in PTC pathogenesis and its potential as a therapeutic target. RESULTS: BANCR expression was significantly lower in PTC samples than in controls, while it was moderately increased in HT samples. In PTC cases with concurrent HT, BANCR expression was markedly reduced compared to normal tissues. Our analysis revealed BANCR's role as an oncogene in PTC, influencing various cancer-related signaling pathways. Interestingly, no significant correlation was found between BANCR expression and lymph node metastasis. CONCLUSION: Our findings underscore the involvement of BANCR in the connection between HT and PTC. The distinct expression patterns of BANCR in PTC and HT, especially in PTC with concurrent HT, provide new insights into the molecular interplay between these conditions. This study opens avenues for the development of innovative diagnostic and therapeutic strategies targeting BANCR in PTC and HT.


Assuntos
Carcinoma Papilar , Doença de Hashimoto , Neoplasias da Glândula Tireoide , Humanos , Câncer Papilífero da Tireoide/genética , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Carcinoma Papilar/genética , Carcinoma Papilar/patologia , Metástase Linfática , Doença de Hashimoto/genética , Doença de Hashimoto/patologia
2.
Psychol Res Behav Manag ; 16: 2667-2680, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37485285

RESUMO

Introduction:  Suicidal ideation and suicidal behavior, as the most severe psychological and behavioral problems among adolescents, bring not only significant damage to individual social functioning but also cause enormous economic and social pressure, which will ultimately be detrimental to social development and social stability. This paper aimed to explore the potential relationship between teacher discrimination behavior, peer bullying victimization, anxiety disorders, and adolescent suicidal ideation based on the Vulnerability-Stress Model. Methods:  From September to November 2022, our research team surveyed 21,017 junior high school students from 12 secondary schools in ten cities in China. Mplus 8.3 software was used to analyze the pathways of teacher discrimination behavior on adolescent suicidal ideation. Results:  The results showed that teacher preference had a significant negative effect on suicidal ideation, and teacher prejudice significantly positively affected suicidal ideation. Mediation test results indicated that there were significant independent mediating effects of peer bullying victimization and anxiety disorders between teacher discrimination behavior and adolescents' suicidal ideation, as well as significant chain mediating effects. Conclusion:  Secondary school teachers should improve their self-quality and pay more attention to adolescents' suicidal ideation. Teachers are expected to put love into their education, respect and trust each student, and attend to their emotional needs unbiasedly. Educators should develop targeted prevention and intervention measures according to the actual situation of school bullying and also strengthen adolescents' life-value education to improve the psychological quality of adolescents and create a healthy campus atmosphere.

3.
Front Public Health ; 11: 1167740, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37361143

RESUMO

Objective: The aim of this study is to examine the extent to which individuals' cognitive evaluation of the importance of the Internet is associated with depressive symptoms, and in what ways. Methods: This study utilized a sample of 4,100 participants from the fourth (2016), fifth (2018), and sixth (2020) waves of the China Family Panel Studies. Structural equation modeling was employed for data analysis. Result: The findings of this study reveal that individuals' cognitive evaluation of the importance of the Internet in 2016 was positively linked with the frequency of Internet use and subjective socioeconomic status in 2018. Furthermore, the frequency of Internet use and subjective socioeconomic status in 2018 were found to be negatively associated with depressive symptoms in 2020. These results indicate that the perceived importance of the Internet has an indirect effect on depressive symptoms through the identified pathway. Conclusion: The present findings contribute to the existing literature by highlighting the importance of individuals' perceived importance of the internet as a significant factor that influences depressive symptoms. The results suggest that policy makers should take actions to increase public awareness of the importance of the Internet in the digital era, and to ensure equitable access to the internet, thus facilitating convenient internet use and helping individuals adapt to the digital age.


Assuntos
Depressão , População do Leste Asiático , Internet , Adulto , Humanos , China/epidemiologia , Depressão/epidemiologia , Depressão/psicologia
4.
Acta Biochim Pol ; 69(4): 711-717, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36520087

RESUMO

BACKGROUND:  Breast cancer (BCa) has been the most commonly diagnosed cancer worldwide and the leading cause of cancer-related death. Dual-specificity phosphatase 28 (DUSP28) is associated with various cancer progression, but its function and mechanism in breast cancer remain unclear. METHODS:  DUSP28 level was identified by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot assays. The proliferation, migration, and invasion of DUSP28 in MCF-7 and MDA-MB-231 cells were assessed by Cell Counting kit-8 (CCK-8), colony formation, and transwell assays. The xenograft tumor model was established to explore the effects of DUSP28 on tumor growth of nude mice. Immunohistochemistry (IHC) and western blot assays were performed to evaluate the expression of related signal molecules. RESULTS:  The expression of DUSP28 was up-regulated in BCa tissues and closely correlated with tumor size and distant lymphatic metastasis in The Cancer Genome Atlas (TCGA) dataset. Quantitative real-time PCR and western blot assays indicated that the expression of DUSP28 was up-regulated in BCa cells. DUSP28 was demonstrated to promote the proliferation, migration, and invasion of MCF-7 and MDA-MB-231 cells in vitro. Knockdown of DUSP28 inhibited tumor growth of xenograft tumor mice in vivo and reduced the levels of DUSP28 and Ki-67. Notably, further mechanism analysis indicated that DUSP28 promoted the activation of Akt/ß-catenin/Slug signaling. CONCLUSION:  DUSP28 exerts its oncogene function via regulating Akt/ß-catenin/Slug signaling in BCa, indicating that DUSP28 may provide a promising therapeutic target for the treatment of BCa.


Assuntos
Neoplasias da Mama , Fosfatases de Especificidade Dupla , Animais , Feminino , Humanos , Camundongos , beta Catenina/genética , beta Catenina/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Camundongos Nus , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatases de Especificidade Dupla/metabolismo
5.
Front Cell Dev Biol ; 10: 913684, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36060798

RESUMO

Background: Understanding interior molecular mechanisms of tumorigenesis and cancer progression contributes to antitumor treatments. The angiotensin II receptor-associated protein (AGTRAP) has been confirmed to be related with metabolic products in metabolic diseases and can drive the progression of hepatocellular carcinoma and colon carcinoma. However, functions of AGTRAP in other kinds of cancers are unclear, and a pan-cancer analysis of AGTRAP has not been carried out. Methods and materials: We downloaded data from The Cancer Genome Atlas and Genotype-Tissue Expression dataset and The Human Protein Atlas databases and then used R software (version 4.1.1) and several bioinformatic tools to conduct the analysis. Results: In our study, we evaluated the expression of AGTRAP in cancers, such as high expression in breast cancer, lung adenocarcinoma, and glioma and low expression in kidney chromophobe. Furthermore, our study revealed that high expression of AGTRAP is significantly related with poor prognosis in glioma, liver cancer, kidney chromophobe, and so on. We also explored the putative functional mechanisms of AGTRAP across pan-cancer, such as endoplasmic reticulum pathway, endocytosis pathway, and JAK-STAT signaling pathway. In addition, the connection between AGTRAP and tumor microenvironment, tumor mutation burden, and immune-related genes was proven. Conclusion: Our study provided comprehensive evidence of the roles of AGTRAP in different kinds of cancers and supported the relationship of AGTRAP and tumorous immunity.

6.
Front Endocrinol (Lausanne) ; 13: 843573, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35360071

RESUMO

Background: The aim of this study is to build a risk assessment system for central lymph node metastasis (CLNM) in papillary thyroid microcarcinoma (PTMC) of stage cN0 and to explore its application value in clinical practice. Methods: A total of 500 patients with PTMC who underwent thyroid operation from 2013 to 2015 in Ningbo First Hospital were selected as the model group. Independent risk factors related to CLNM in PTMC were analyzed and determined, and a risk assessment system for CLNM was preliminarily established. Furthermore, the clinicopathological data from 328 PTMC patients with the same conditions as the model group from 2016 to 2017 were further collected as the validation group to verify the diagnostic value of the risk assessment system. Results: The risk assessment system was based on the score rating (score ≤ 5 was classified as low risk, 6-8 was classified as medium risk, and ≥9 was classified as high-risk). The area under the receiver operating characteristic curve (ROC) was 0.687 (95% CI: 0.635-0.783). According to the risk assessment system, 328 PTMC patients in the validation group were scored. Among the low-risk group, the moderate-risk group, and the high-group, 96.8%, 58.1%, and 43.2% were the CLNM (-) patients, and 3.1%, 41.9%, and 65.8% were CLNM (+) patients, respectively. The area under ROC was 0.837 (95% CI: 0.778-0.869). Conclusions: The risk assessment system in this study is of diagnostic value and can provide a theoretical foundation for intraoperative decision-making of prophylactic central neck dissection (pCND).


Assuntos
Carcinoma Papilar , Carcinoma Papilar/patologia , Carcinoma Papilar/cirurgia , Humanos , Metástase Linfática , Estudos Retrospectivos , Medição de Risco , Neoplasias da Glândula Tireoide
7.
Arch Insect Biochem Physiol ; 110(4): e21903, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35416322

RESUMO

Aphis glycines Matsumura (Hemiptera: Aphididae) is a major soybean pest that often poses a serious threat to soybean production. In this study, we checked the effects of acetamiprid on redox, energy metabolism, and hormone expression in A. glycines. The LC50 and LC30 of acetamiprid were used to treat the fourth instar nymphs in each generation from F0 to F4 to measure the activity of peroxidase, pyruvate kinase, and trehalase using a microassays approach. The peroxidase activity was significantly higher than control when treated with the LC30 of acetamiprid in F2-F5 generations. The activity of pyruvate kinase was significantly higher, while trehalase activity was substantially lower than control in each generation. Besides, we monitored molting and juvenile hormone expression in soybean aphids using enzyme-linked immunosorbent assay. The juvenile hormone titer of third instar nymphs was significantly higher in the treatment group (F1, F2, F4, and F5), while no effects were noted in the F3 generation. Taken together, the activity of peroxidase and pyruvate kinase in soybean aphid first increased to the peak and then decreased, while the trehalase activity continuously decreased in all generations following exposure to acetamiprid. The juvenile hormone titer was significantly higher, while the molting hormone titer was significantly lower in LC50 -treated aphids than in control. Moreover, the LC30 of acetamiprid increased the molting hormone expression in soybean aphids. These findings indicated a baseline for the effective use of acetamiprid in controlling soybean aphids.


Assuntos
Afídeos , Animais , Afídeos/fisiologia , Ecdisona , Hormônios Juvenis , Neonicotinoides , Ninfa , Peroxidases , Piruvato Quinase , Glycine max , Trealase
8.
Aging (Albany NY) ; 14(2): 845-868, 2022 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-35060926

RESUMO

BACKGROUND: Breast cancer is an invasive disease with complex molecular mechanisms. Prognosis-related biomarkers are still urgently needed to predict outcomes of breast cancer patients. METHODS: Original data were download from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO). The analyses were performed using perl-5.32 and R-x64-4.1.1. RESULTS: In this study, 1086 differentially expressed genes (DEGs) were identified in the TCGA cohort; 523 shared DEGs were identified in the TCGA and GSE10886 cohorts. Eight subtypes were estimated using non-negative matrix factorization clustering with significant differences seen in overall survival (OS) and progression-free survival (PFS) (P < 0.01). Univariate Cox analysis and least absolute shrinkage and selection operator (LASSO) regression analysis were performed to develop a related risk score related to the 17 DEGs; this score separated breast cancer into low- and high-risk groups with significant differences in survival (P < 0.01) and showed powerful effectiveness (TCGA all group: 1-year area under the curve [AUC] = 0.729, 3-year AUC = 0.778, 5-year AUC = 0.781). A nomogram prediction model was constructed using non-negative matrix factorization clustering, the risk score, and clinical characteristics. Our model was confirmed to be related with tumor microenvironment. Furthermore, DEGs in high-risk breast cancer were enriched in histidine metabolism (normalized enrichment score [NES] = 1.49, P < 0.05), protein export (NES = 1.58, P < 0.05), and steroid hormone biosynthesis signaling pathways (NES = 1.56, P < 0.05). CONCLUSIONS: We established a comprehensive model that can predict prognosis and guide treatment.


Assuntos
Neoplasias da Mama , Microambiente Tumoral , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Prognóstico , Microambiente Tumoral/genética
9.
Insects ; 13(1)2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-35055930

RESUMO

The soybean aphid Aphis glycines Matsumura (Hemiptera: Aphididae) is a major pest of soybean and poses a serious threat to soybean production. Studies on the effect of acetamiprid on the life table parameters of A. glycines, provide important information for the effective management of this pest. We found that exposure to acetamiprid at LC50 significantly extended the mean generation time, adult pre-reproductive period, and total pre-reproduction period compared with the control, whereas exposure to acetamiprid at LC30 significantly shortened these periods. Exposure to acetamiprid at both LC30 and LC50 significantly decreased the fecundity of the female adult, net reproductive rate, intrinsic rate of increase, and finite rate of increase compared with the control. The probability of attaining the adult stage was 0.51, 0.38, and 0.86 for a newly born nymph from the LC30 acetamiprid treatment group, LC50 acetamiprid treatment group, and control group, respectively. Acetamiprid at both LC50 and LC30 exerted stress effects on A. glycines, with the LC50 treatment significantly decreased the growth rate compared with the LC30 treatment. The present study provides reference data that could facilitate the exploration of the effects of acetamiprid on A. glycines in the field.

10.
Sci Total Environ ; 817: 153004, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35026254

RESUMO

Marine suspended particles are unique micro-habitats for diverse microbes and also hotspots of microbially metabolic activities. However, the association of bacterial pathogens, especially those carrying antibiotic resistance genes (ARGs), with these particles remain largely unknown in coastal habitats. This study investigated the distribution of pathogen-related bacteria and ARGs in particle-associated (PA) and free-living (FL) fractions of samples collected at three coastal beaches using NextGen sequencing and qPCR. Suspended particles were found to harbor significantly higher abundances of bacteria of pathogen-related genera and ARGs than their counterparts. Functional analysis of microbial community suggested that antibiotic biosynthetic pathways were also more abundant among PA microbiome comparing to FL microbial community, which further facilitated the spread of ARGs. Additionally, 13 pathogen-related genera co-occurred with ARG in PA fraction while only 2 pathogen-related genera co-occurred with ARGs in FL fraction. Overall, our research revealed suspended particles harbored more abundant pathogen-related genera and ARGs comparing with surrounding waters. Thus, suspended particles are hotspots for pathogen-related genera and ARGs and may pose a greater threat to human health in coastal beach.


Assuntos
Antibacterianos , Microbiota , Antibacterianos/farmacologia , Bactérias/genética , China , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Humanos
11.
Sensors (Basel) ; 20(17)2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32867175

RESUMO

Automated and high-accuracy three-dimensional (3D) shape measurement is required in quality control of large-size components for the aerospace industry. To eliminate the contradiction between global measurement and local precision measurement control in 3D digitalization for the key local features of the large-size components, a combined measurement method is proposed, including a 3D scanner, a laser tracker, and an industrial robot used as an orienting device, to achieve high-accuracy measurement. As for improving the overall measurement accuracy, an accurate calibration method based on coordinate optimization of common points (COCP) and coordinate optimization of global control points (COGP) is proposed to determine the coordinate systems. Firstly, a coordinate optimization method of common points (COCP) is recommended. Then, a coordinate optimization method of global control points (COGP) based on the angular constraint is proposed for minimizing the measurement errors and improving the measurement accuracy of the position and orientation of the 3D scanner. Finally, a combined measurement system is established, and validation experiments are carried out in laboratory within a distance of 4 m. The calibration experiment results demonstrate that the max and mean errors of the coordinate transformation have been reduced from 0.037 and 0.022 mm to 0.021 and 0.0122 mm. Additionally, the measurement experiment results also show that the combined measurement system features high accuracy.

12.
Int J Biol Macromol ; 163: 1915-1925, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32931828

RESUMO

A new type of double-network hydrogel, cross-linked with microcrystalline cellulose grafted with ε-polylysine (MCC-PL) and N,N-methylene bisacrylamide/acrylic acid, was synthesised to efficiently inhibit bacterial proliferation and remove heavy metals. The physicochemical properties of the MCC-PL hydrogel (MCC-PLH) were characterised using scanning electronic microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, and differential thermogravimetric analysis. The adsorption results showed that the optimal adsorption conditions were temperature of 313 K at pH of 5 and 6 of Pb2+ and Cu2+, respectively. The adsorption mechanism of MCC-PLH5 was successfully determined using Freundlich isotherm, pseudo-second kinetics, and intra-particle diffusion model, in conjunction with X-ray photoelectron spectroscopy. Adsorption thermodynamic studies indicated that the process was spontaneous and endothermic. Antibacterial experiments showed that PL-grafted MCC hydrogel exhibited more efficient and durable antibacterial activity than MCC, indicating its potential for water decontamination.


Assuntos
Celulose/química , Hidrogéis/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção/efeitos dos fármacos , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Celulose/síntese química , Celulose/farmacologia , Hidrogéis/síntese química , Hidrogéis/farmacologia , Metais Pesados/química , Metais Pesados/isolamento & purificação , Microscopia Eletrônica de Varredura , Polilisina/química , Espectroscopia de Infravermelho com Transformada de Fourier , Água/química , Poluentes Químicos da Água/química
13.
Artigo em Inglês | MEDLINE | ID: mdl-32414023

RESUMO

Erythromycin is a widely used antibiotic, and erythromycin contamination may pose a threat to aquatic organisms. However, little is known about the adverse effects of erythromycin on swimming ability. To quantify erythromycin-induced damage to fish swimming ability, Oryzias latipes and Danio rerio were acutely exposed to erythromycin. The swimming ability of the experimental fish was measured after exposure to varying doses of erythromycin (2 µg/L, 20 µg/L, 200 µg/L, and 2 mg/L) for 96 h. Burst speed (Uburst) and critical swimming speed (Ucrit) of experimental fish significantly decreased. In addition, gene expression analysis of O. latipes and D. rerio under erythromycin treatment (2 mg/L) showed that the expression of genes related to energy metabolism in the muscle was significantly reduced in both species of fish. However, the gene expression pattern in the head of the two species was differentially impacted; D. rerio showed endocrine disruption, while phototransduction was impacted in O. latipes. The results of our study may be used as a reference to control erythromycin pollution in natural rivers.


Assuntos
Eritromicina , Natação , Poluentes Químicos da Água , Animais , Eritromicina/toxicidade , Oryzias , Poluentes Químicos da Água/toxicidade , Peixe-Zebra
14.
Front Oncol ; 10: 616098, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33614498

RESUMO

Triple negative breast cancer (TNBC) is a subtype of breast cancer with strong aggressiveness and poor clinical treatment effect, accounting for about 10-20% of breast cancer cases. N(6)-methyldeoxyadenosine (6mA) is the most conservative DNA modification in prokaryotes and eukaryotes. It is widely found in bacteria and has such functions as DNA mismatch repair, chromosome separation and virulence regulation. We determined that 6mA was modified in TNBC cell line MDA-MB-231 and the TNBC tissue. Meanwhile, compared with normal tissues, the expression level of 6mA and its methylase N6AMT1 was significantly decreased in TNBC tissue. MDA-MB-231cells were cultured with 8µM Olaparib for 2 months to construct drug-resistant cell line 231-RO. It was found that the level of 6mA also increased significantly, and the expression of N6AMT1 or ALKBH1 could effectively influence the drug resistance. Subsequently, we found that LINP1 was highly expressed in 231-RO, which was involved in DNA repair, and the expression of LINP1 could be positively regulated by 6mA modification. LINP1 expression level is directly related to TNBC drug resistance. The above results indicate that 6mA may be a new biological marker of TNBC. Meanwhile, 6mA modification may be involved in the regulation of Olaparib resistance.

15.
Mitochondrial DNA B Resour ; 1(1): 58-59, 2016 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33490387

RESUMO

Pareuchiloglanis gongshanensis, a small-sized benthic fish, distributed in southwest China. In the present study, the complete mitochondrial genome of P. gongshanensis was sequenced to be 16 588 bp in length, including 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes, a control region and the origin of the light strand replication. The overall nucleotide composition was 30.70% A, 24.11% T, 29.16% C and 16.02% G, with an A + T bias of 54.82%. The gene composition and the structural arrangement of the P. gongshanensis complete mitochondrial DNA were identical to most of the other vertebrates. This will provide a useful tool for understanding the genetic diversity, population structure and conservation status of P. gongshanensis in the future.

16.
Gene ; 508(1): 60-72, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-22868207

RESUMO

The superfamily Cobitoidea of the order Cypriniformes is a diverse group of fishes, inhabiting freshwater ecosystems across Eurasia and North Africa. The phylogenetic relationships of this well-corroborated natural group and diverse clade are critical to not only informing scientific communities of the phylogeny of the order Cypriniformes, the world's largest freshwater fish order, but are key to every area of comparative biology examining the evolution of traits, functional structures, and breeding behaviors to their biogeographic histories, speciation, anagenetic divergence, and divergence time estimates. In the present study, two mitochondrial gene sequences (COI, ND4+5) and four single-copy nuclear gene segments (RH1, RAG1, EGR2B, IRBP) were used to infer the phylogenetic relationships of the Cobitoidea as reconstructed from maximum likelihood (ML) and partitioned Bayesian Analysis (BA). Analyses of the combined mitochondrial/nuclear gene datasets revealed five strongly supported monophyletic Cobitoidea families and their sister-group relationships: Botiidae+(Vaillantellidae+(Cobitidae+(Nemacheilidae+Balitoridae))). These recovered relationships are in agreement with previous systematic studies on the order Cypriniformes and/or those focusing on the superfamily Cobitoidea. Using these relationships, our analyses revealed pattern lineage- or ecological-group-specific evolution of these genes for the Cobitoidea. These observations and results corroborate the hypothesis that these group-specific-ancestral ecological characters have contributed in the diversification and/or adaptations within these groups. Positive selections were detected in RH1 of nemacheilids and in RAG1 of nemacheilids and genus Vaillantella, which indicated that evolution of RH1 (related to eye's optic sense) and RAG1 (related to immunity) genes appeared to be important for the diversification of these groups. The balitorid lineage (those species inhabiting fast-flowing riverine habitats) had, as compared with other cobitoid lineages, significantly different dN/dS, dN and dS values for ND4 and IRBP genes. These significant differences are usually indicative of weaker selection pressure, and lineage-specific evolution on genes along the balitorid lineage. Furthermore, within Cobitoidea, excluding balitorids, species living in subtropics had significantly higher dN/dS values in RAG1 and IRBP genes than those living in temperate and tropical zones. Among tropical cobitoids, genes COI, ND5, EGR2B, IRBP and RH1, had a significantly higher mean dS value than those species in subtropical and temperate groups. These findings suggest that the evolution of these genes could also be ecological-group-specific and may have played an important role in the adaptive evolution and diversification of these groups. Thus, we hypothesize that the genes included in the present study were actively involved in lineage- and/or ecological-group-specific evolutionary processes of the highly diverse Cobitoidea. These two evolutionary patterns, both subject to further testing, are hypothesized as integral in the diversification with this major clade of the world's most diverse group of freshwater fishes.


Assuntos
Evolução Biológica , Cipriniformes/classificação , Cipriniformes/genética , Genes Mitocondriais , Proteínas Nucleares/genética , Animais , Teorema de Bayes , Filogenia
17.
Dongwuxue Yanjiu ; 31(3): 221-9, 2010 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-20672409

RESUMO

In the present study, we cloned and sequenced 10 new ND4 and ND5 gene sequences of Cobitoidea. These sequences were used to reconstruct phylogenetic relationships together with those of 15 other species downloaded from GenBank. The results showed that the length of ND4 gene sequence was 1 380-1 387 bp with ATG as starting codon and incomplete termination signal as terminated codon; the length of ND5 gene sequence was 1 821-1 839 bp with ATG as starting codon and TAA or TAG as terminated codon; three tRNA genes coding tRNAs that carry hisidine, serine and leucine respectively, were inserted between ND4 and ND5 genes. A, T, C and G accounted for 30.4%, 27.3%, 14.2% and 28.1% in ND4/ND5 gene (including intervening three tRNA genes). The content of A+T (57.7%) is higher than that of G+C (42.3%). The estimated Ti/Tv ratio was 1.586. With Danio rerio and Cyprinus carpio as outgroups, the phylogenetic relationships of Cobitoidea were analyzed using maximum parsimony (MP) method, maximum likelihood (ML) method and Bayesian analyses (BI). Results of all the three methods indicated that Cobitinae, Nemacheilinae, Botiinae, Balitoridae and Vaillantellidae were all monophyletic respectively, and their interrelationships were: (Vaillantellidae + (Botiinae + (Cobitinae + (Nemacheilinae + Balitoridae)))), which was consistent with the previous studies based on the whole mitogenome and some nuclear genes sequences (eg. RAG1 gene). However, the present results differ from those based upon other mtDNA genes sequences (e.g. the cyt b and D-loop showed that Nemacheilinae grouped with Cobitinae forming sister-group, then they clustered with Balitoridae). The difference could be due to the phylogenetic information carried by different length sequence: Longer sequences carry more information and result in more reliable phylogenetic trees.


Assuntos
Cipriniformes/classificação , DNA Mitocondrial/genética , Genes RAG-1/genética , Mitocôndrias/genética , Filogenia , RNA de Transferência/genética , Animais , Sequência de Bases , Teorema de Bayes , Cipriniformes/genética , DNA Mitocondrial/classificação , Complexo I de Transporte de Elétrons/genética , Evolução Molecular , Testes Genéticos , Humanos , Proteínas Mitocondriais/genética , Dados de Sequência Molecular
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