Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 54
Filtrar
Filtros adicionais











Intervalo de ano
1.
Biosci Rep ; 39(3)2019 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-30777932

RESUMO

Akirin1 is found to be involved in myoblast differentiation. However, the mechanism by which the Akirin1 gene regulates myoblast differentiation still remains unclear. In the present study, we found that ectopic expression of Akirin1 promoted myoblast differentiation by increasing the expression of myogenic regulatory factor (MRF) 4 (MRF4) and myocyte enhancer factor 2B (MEF2B) mRNA. Additionally, we showed that ectopic Akirin1 induced cell cycle arrest by up-regulating p21 mRNA. To further uncover the mechanism by which Akirin1 promotes myoblast differentiation, we showed that the enhanced Akirin1 increased the mRNA expression of P38α. Importantly, the enhanced MRF4 expression by Akirin1 can be abrogated by treatment of SB203580, a p38 inhibitor. Similarly, we found that enhanced MEF2B expression by Akirin1 can be abrogated by treatment with LY294002, a PI3K inhibitor. Together, our results indicate that Akirin1 promotes myoblast differentiation by acting on the p38 and PI3K pathways and subsequently inducing the expression of myoblast differentiation factors.

2.
J Therm Biol ; 80: 75-81, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30784491

RESUMO

Avian embryos are an ideal system to investigate the effect of incubation temperature on embryonic development, but the characteristics and mechanisms of temperature effects on poultry embryonic myogenesis are unclear. In this study, we investigated the effect of increasing the incubation temperature by 1 °C on the expression of nine myogenesis-related genes in ducks and then explored the correlation between the alteration of promoter methylation and the expression of two of the nine genes under thermal manipulation (TM). The qRT-PCR results showed that TM during embryonic days (ED) 1-10 promoted (P < 0.05) the expression of genes in breast muscle (PAX3, PAX7, MYOG, MCK, SIX1, TNNC1) and leg muscle (MYOD, MYOG, MYF5, MCK, AKIRIN2, TNNC1). TM during ED10-20 promoted the expression of PAX3, MYF5 and MCK and inhibited AKIRIN2 expression in breast muscle (P < 0.05); however, it inhibited the expression of PAX3, PAX7, MYOD, MYOG, MYF5, SIX1, AKIRIN2 and TNNC1 and promoted MCK expression in leg muscle (P < 0.05). TM during ED20-27 inhibited the expression of genes in breast muscle (PAX7) and leg muscle (MYOD, MYOG, MYF5, TNNC1) and promoted MCK expression in breast and leg muscle (P < 0.05). Furthermore, with the Sequenom MassARRAY platform, it was observed that the average methylation level of AKIRIN2 (ED10) and TNNC1 (ED20) in leg muscle decreased (P < 0.05) after TM. Notably, we found significant (P < 0.05) inverse correlations between the methylation and mRNA levels of AKIRIN2 under TM during ED1-10 (r = - 0.969) and ED10-20 (r = - 0.805). Taken together, TM during ED1-10 was more favorable for improving duck myogenesis-related gene expression than TM during ED10-20 and ED20-27. TM during duck embryogenesis seemed to have a greater effect on the development of leg muscle than breast muscle and might alter AKIRIN2 expression by changing its promoter methylation status. These findings may be helpful to understand temperature effects on the muscle development of avian embryos and to explore the role of epigenetic regulation during this process.


Assuntos
Proteínas Aviárias/fisiologia , Patos , Desenvolvimento Embrionário/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Desenvolvimento Muscular/fisiologia , Músculo Esquelético , Temperatura Ambiente , Animais , Patos/embriologia , Patos/fisiologia , Metilação , Músculo Esquelético/embriologia , Músculo Esquelético/fisiologia , Regiões Promotoras Genéticas
3.
Poult Sci ; 98(5): 2260-2271, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30624718

RESUMO

The blue-shelled egg not only plays a key role in helping birds to avoid predation as a result of crypsis and mimetism, but it also provides eggshell strength and filters solar radiation; moreover, it has an important economic trait for poultry. However, the source of biliverdin for blue-shelled egg remains unsolved in ducks. The current study detected the biliverdin content and localization of heme oxygenase 1 (HMOX1) in duck shell gland; moreover, RNA-seq analysis was performed in the shell gland of blue-shelled and white-shelled ducks. Results indicated that biliverdin is a primary pigment for blue-shelled egg in ducks, and the HMOX1 protein showed high expression in ciliated epithelial cells of shell gland between blue-shelled and white-shelled ducks. In the pathway of biliverdin synthesis, only 5-aminolevulinate synthase 1 expression level was significantly upregulated in blue-shelled ducks, and nuclear factor, erythroid 2 like 1 and period circadian clock 2 may be the essential elements in biliverdin synthesis of duck shell gland. Furthermore, some of the transporter genes, such as activator-Like and solute carrier family 13 member 5, may be involved in the formation of blue egg in duck. Results of the current study suggested that the biliverdin is most likely synthesized and secreted from epithelial cells of shell gland. In addition, ALAS1 may play a key role in the formation of blue egg in ducks.


Assuntos
Biliverdina/genética , Patos/genética , Oviductos/metabolismo , Pigmentação/genética , Transcriptoma , Animais , Biliverdina/metabolismo , Cor , Patos/metabolismo , Casca de Ovo/fisiologia , Glândulas Exócrinas/metabolismo , Feminino
4.
Anim Reprod Sci ; 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30522702

RESUMO

Bone morphogenetic protein 4 (BMP4) has an important role in regulating cellular proliferation, differentiation and apoptosis. It, however, is still unclear as to the mechanisms by which BMP4 regulates the apoptosis of granulosa cells (GCs) in geese. In the present study, there was cloning of the full-length coding sequence of goose BMP4 gene, which consisted of 1212 nucleotides encoding 403 amino acids. Its deduced amino acid sequence comprised one signal peptide, one TGFß pro-peptide and one mature peptide domain. Results from conducting the quantitative real-time PCR (qPCR) indicated the relative abundances of BMP4 mRNA in geese GCs increased gradually from the relative abundances in pre-hierarchical follicles that were 4 to 6 mm in diameter to that in the fifth largest (F5) follicle and then relative abundances of BMP4 mRNA decreased with further development as the largest (F1) follicle. Results from use of the TUNEL assay indicated that overexpression of the goose BMP4 gene suppressed GC apoptosis and this was confirmed when relative abundances of the CAD, Caspase-9 and Caspase-3 proteins were determined using western blotting. In addition, overexpression of the BMP4 gene induced phosphorylation of AKT, which was inhibited with use of the PI3K inhibitor, LY294002. Co-transfection of BMP4 and LY294002 resulted in increased relative abundances of Caspase-9 and CAD proteins but had no effect on that of Caspase-3. Taken together, these results suggested that expression of the BMP4 gene resulted in a reduction in Caspase-9 protein leading to inhibition of GC apoptosis via the PI3K/AKT signaling pathway in geese.

5.
Front Genet ; 9: 520, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30425731

RESUMO

Short tandem repeats (STRs) are usually associated with genetic diseases and gene regulatory functions, and are also important genetic markers for analysis of evolutionary, genetic diversity and forensic. However, for the majority of STRs in the duck genome, their population genetic properties and functional impacts remain poorly defined. Recent advent of next generation sequencing (NGS) has offered an opportunity for profiling large numbers of polymorphic STRs. Here, we reported a population-scale analysis of STR variation using genome resequencing in mallard and Pekin duck. Our analysis provided the first genome-wide duck STR reference including 198,022 STR loci with motif size of 2-6 base pairs. We observed a relatively uneven distribution of STRs in different genomic regions, which indicates that the occurrence of STRs in duck genome is not random, but undergoes a directional selection pressure. Using genome resequencing data of 23 mallard and 26 Pekin ducks, we successfully identified 89,891 polymorphic STR loci. Intensive analysis of this dataset suggested that shorter repeat motif, longer reference tract length, higher purity, and residing outside of a coding region are all associated with an increase in STR variability. STR genotypes were utilized for population genetic analysis, and the results showed that population structure and divergence patterns among population groups can be efficiently captured. In addition, comparison between Pekin duck and mallard identified 3,122 STRs with extremely divergent allele frequency, which overlapped with a set of genes related to nervous system, energy metabolism and behavior. The evolutionary analysis revealed that the genes containing divergent STRs may play important roles in phenotypic changes during duck domestication. The variation analysis of STRs in population scale provides valuable resource for future study of genetic diversity and genome evolution in duck.

6.
Nat Commun ; 9(1): 3974, 2018 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-30254288

RESUMO

In the original version of this Article, there was an error in the legend for Figure 2, whereby the descriptions of panels a, b and c were presented in a different order to the corresponding figure panels. The text 'a GWAS of duck plumage color, including 76 colored ducks and 30 white Pekin ducks. The gray horizontal dashed lines indicate the Bonferroni significance threshold of the GWAS (1 × 10-9). b Fixation index (FST) of all SNPs along chromosome 13 between mallards and Pekin ducks. Red dots indicate fixed SNPs. c The nucleotide diversity (π) of mallards (blue line) and Pekin ducks (red line) from 16.0 to 17.0 Mb on chromosome 13.' should have read 'a Fixation index (FST) of all SNPs along chromosome 13 between mallards and Pekin ducks. Red dots indicate fixed SNPs. b The nucleotide diversity (π) of mallards (blue line) and Pekin ducks (red line) from 16.0 to 17.0 Mb on chromosome 13. c GWAS of duck plumage color, including 76 colored ducks and 30 white Pekin ducks. The gray horizontal dashed lines indicate the Bonferroni significance threshold of the GWAS (1 × 10-9).' This has been corrected in both the PDF and HTML versions of the Article.

7.
Hum Gene Ther ; 2018 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-30101608

RESUMO

Hereditary retinal dystrophy is clinically defined as a broad group of chronic and progressive disorders that affect visual function by causing photoreceptor degeneration. Previously, we identified mutations in the gene encoding receptor expression-enhancing protein 6 (REEP6), in individuals with autosomal recessive retinitis pigmentosa (RP), the most common form of inherited retinal dystrophy. One individual was molecularly diagnosed with biallelic REEP6 mutations, a missense mutation over a frameshift mutation. In this study, we generated Reep6 compound heterozygous mice, Reep6L135P/-, which mimic the patient genotype and recapitulate the early-onset retinal degeneration phenotypes observed in the individual with RP. To determine the feasibility of rescuing the Reep6 mutant phenotype via gene replacement therapy, we delivered Reep6.1, the mouse retina-specific isoform of REEP6, to photoreceptors of Reep6 mutant mice on postnatal day 20. Evaluation of the therapeutic effects 2 months posttreatment showed improvements in the photoresponse as well as preservation of photoreceptor cells. Importantly, guanylyl cyclase 1 (GC1) expression was also restored to the outer segment after treatment. Furthermore, rAAV8-Reep6.1 single treatment in Reep6 mutant mice 1 year postinjection showed significant improvements in retinal function and morphology, suggesting that the treatment is effective even after a prolonged period. Findings from this study show that gene replacement therapy in the retina with rAAV overexpressing Reep6 is effective, preserving photoreceptor function in Reep6 mutant mice. These findings provide evidence that rAAV8-based gene therapy can prolong survival of photoreceptors in vivo and can be potentially used as a therapeutic modality for treatment of patients with RP.

8.
Biomed Res Int ; 2018: 8120263, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29967787

RESUMO

Hypocretin system is composed of hypocretins (hcrts) and their receptors (hcrtrs), which has multiple vital functions. Hypocretins work via hypocretin receptors and it is reported that functional differentiation occurred in hcrtrs. It is necessary to figure out the evolution process of hypocretin receptors. In our study, we adopt a comprehensive approach and various bioinformatics tools to analyse the evolution process of HCRTR gene family. It turns out that the second round of whole genome duplication in early vertebrate ancestry and the independent round in fish ancestry may contribute to the diversity of HCRTR gene family. HCRTR1 of fishes and mammals are not the same receptor, which means that there are three members in the family. HCRTR2 is proved to be the most ancient one in HCRTR gene family. After duplication events, the structure of HCRTR1 diverged from HCRTR2 owing to relaxed selective pressure. Negative selection is the predominant evolutionary force acting on the HCRTR gene family but HCRTR1 of mammals is found to be subjected to positive selection. Our study gains insight into the molecular evolution process of HCRTR gene family, which contributes to the further study of the system.

9.
Nat Commun ; 9(1): 2648, 2018 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-30018292

RESUMO

Comparative population genomics offers an opportunity to discover the signatures of artificial selection during animal domestication, however, their function cannot be directly revealed. We discover the selection signatures using genome-wide comparisons among 40 mallards, 36 indigenous-breed ducks, and 30 Pekin ducks. Then, the phenotypes are fine-mapped based on resequencing of 1026 ducks from an F2 segregating population generated by wild × domestic crosses. Interestingly, the two key economic traits of Pekin duck are associated with two selective sweeps with fixed mutations. A novel intronic insertion most possibly leads to a splicing change in MITF accounted for white duck down feathers. And a putative long-distance regulatory mutation causes continuous expression of the IGF2BP1 gene after birth which increases body size by 15% and feed efficiency by 6%. This study provides new insights into genotype-phenotype associations in animal research and constitutes a promising resource on economically important genes in fowl.

10.
Mol Immunol ; 101: 120-129, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29933212

RESUMO

As a central immune organ unique to birds, the bursa of Fabricius (BF) provides a proper microenvironment for B-cell development. The bursal B-cells undergo rapid proliferation and differentiation at the embryonic stages, but 95% of them undergo apoptosis after hatching. Few studies have focused on the cause of bursal B-cells apoptosis at the embryonic stages in birds. To explore the cause, we compared the transcriptional profiles of three characteristic embryonic stages in duck, including embryonic day 14 (ED14), 22 (ED22) and 1 day after hatching (D1). Our results showed that the apoptotic B-cells were first observed at ED22 while there were no apoptotic B-cells at ED14. By performing enrichment analysis for DEGs and qRT-PCR, our results demonstrated that both mitochondrial and Fas signaling pathways mediated bursal B-cell apoptosis during the duck embryonic development. Further, protein-protein interactions (PPIs) and KEGG enrichment analysis together showed that BMP4, FoxO1 and IGF-1 may regulate bursal B-cells apoptosis. In addition, the DEGs showed two stage-specific expression patterns. By analyzing the genes of two expression patterns, the results indicated that B-cell false differentiation may be one of the reasons of apoptosis in the duck embryonic BF. Overall, these data demonstrated that from ED14-ED22, apoptosis of bursal B-cells was mediated by mitochondrial and Fas signaling pathways and could be regulated by BMP4, FoxO1 and IGF-1 in duck. One of the primary causes of bursal B-cell apoptosis may be false differentiation in B-cells.

12.
Asian-Australas J Anim Sci ; 31(10): 1575-1580, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29642677

RESUMO

OBJECTIVE: This study was conducted to estimate the genetic parameters and breeding values of breast meat related traits of Pekin ducks. Selection response was also determined by using ultrasound breast muscle thickness (BMT) measurements in combination with bosom breadth (BB) and keel length (KL) values. METHODS: The traits analyzed were breast meat weight (BMW), body weight (BW), breast meat percentage (BMP) and the three parameters of breast meat (BB, KL, and BMT). These measurements were derived from studying 15,781 Pekin ducks selected from 10 generations based on breast meat weight. Genetic parameters and breeding value were estimated for the analysis of the breeding process. RESULTS: Estimated heritability of BMW and BMP were moderate (0.23 and 0.16, respectively), and heritability of BW was high (0.48). Other traits such as BB, KL, and BMT indicated moderate heritability ranging between 0.11 and 0.28. Significant phenotypic correlations of BMW with BW and BMP were discovered (p<0.05), and genetic correlations of BMW with BW and BMP were positive and high (0.83 and 0.66, respectively). It was noted that BMW had positive correlations with all the other traits. Generational average estimated breeding values of all traits increased substantially over the course of selection, which demonstrated that the ducks responded efficiently to increased breast meat yield after 10 generations of breeding. CONCLUSION: The results indicated that duck BMW had the potential to be increased through genetic selection with positive effects on BW and BMP. The ultrasound BMT, in combination with the measurement of BB and KL, is shown to be essential and effective in the process of high breast meat yield duck breeding.

13.
Gene ; 658: 184-190, 2018 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-29544766

RESUMO

As a key member of the cytochrome P450 gene superfamily, CYP17 gene encodes 17α-hydroxylase/C17,20-lyase that is critical for directing androgen synthesis. The CYP17 gene has been identified in several species, yet little is known about its distribution and expression profile during goose follicular development. In the present study, we obtained the full-length coding sequence of goose CYP17 (gCYP17) gene for the first time using RACE method. Its sequence alignment and phylogenetic analysis suggested that gCYP17 was highly conserved with those of other birds and consisted of four main functional domains like other species. Results from immunohistochemistry, quantitative real-time PCR and Western blotting suggested that gCYP17 was predominantly located in theca interna throughout follicular development. Furthermore, levels of gCYP17 reached the maximum in theca layer of the 6-8 mm follicles which were significantly higher than in those of other follicles (P < 0.05). In addition, gCYP17 was expressed at much higher levels in the F4 theca layer than the F1 follicle (P < 0.05). Therefore, these results indicated that the fluctuating expression pattern and specific cellular localization of gCYP17 during follicular development might be closely related to androgen secretion, and thereby follicular maturation.


Assuntos
Gansos/genética , Folículo Ovariano/fisiologia , Esteroide 17-alfa-Hidroxilase/genética , Esteroide 17-alfa-Hidroxilase/metabolismo , Animais , Clonagem Molecular , Feminino , Gansos/fisiologia , Regulação Enzimológica da Expressão Gênica , Folículo Ovariano/metabolismo , Oviparidade/genética , Análise de Sequência de DNA , Distribuição Tecidual
14.
PLoS One ; 13(2): e0191213, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29408859

RESUMO

Geese have the strongest tendency toward broodiness among all poultry. The mechanisms initiating broodiness within the goose hypothalamic-pituitary-gonadal axis (HPGA) are still unclear. Here, we reported the transcriptome differences between laying and initial nesting within the HPGA tissues of geese. We constructed a unigene database based on HPGA tissues and identified 128,148 unigenes, 100% of which have been annotated. By using Digital Gene Expression (DGE) sequencing, we screened 19, 110, 289, and 211 differentially expressed genes (DEGs) in the hypothalamus, pituitary gland, stroma ovarii, and follicles, respectively, between laying and nesting geese. Expression changes of hypocretin (HCRT) and pro-opiomelanocortin (POMC) in the hypothalamus of nesting geese may cause appetite reduction, which is possibly the first step and a prerequisite to initiate broodiness. In addition to prolactin (PRL), follicle-stimulating hormone (FSH) and luteinizing hormone (LH), genes including oxytocin-neurophysin (OXT), chordin-like protein 1 (CHRDL1) and growth hormone (GH), expressed in the pituitary gland, are new candidate molecules that may be involved in broodiness in geese. Heme oxygenase 1 (HMOX1) in the pituitary gland, the proto-oncogene c-Fos (FOS), heat shock protein 90-alpha (HSP90AA), and cyclin-dependent kinase 1 (CDK1) in the ovary that may consolidate and transduce signals regulating the HPGA during broodiness in geese.


Assuntos
Gônadas/fisiologia , Sistema Hipotálamo-Hipofisário/fisiologia , Transcriptoma , Animais , Feminino , Gansos , Expressão Gênica
15.
J Therm Biol ; 70(Pt B): 37-45, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29108556

RESUMO

Poultry embryos are easily affected by environmental changings during incubation, thereinto, the temperature modification is the most important one, but the mechanism of temperature effects on bird eggs is not clear. By using RNA-seq, we have previously found that endoplasmic reticulum stress (ERS) may involve in regulating embryonic muscle development of duck under the influence of temperature alteration. To further clarify the role of ERS in the effect, in the present study, we detected the impact of increasing the incubation temperature by 1℃ during embryonic days 10-27 (E10-27) on the development of duck embryos, and investigated the changes in mRNA and protein expression of ERS marker genes and muscle-related genes under the thermal manipulation (TM). The results of relative weight comparison showed that only the relative weight of breast muscle was steadily decreased by TM from E10 to the first day after hatching (W0). Meanwhile, the real-time PCR and western-blot analysis revealed that raising the incubation temperature stimulated the expression of ERS marker genes in breast muscle at E20. The mRNA expressions of muscle hypertrophy and atrophy-related genes were also detected, and were not changed regularly, however, the protein expressions of hypertrophy-related genes were all decreased at both E20 and W0, and the protein expression of atrophy-related genes were up-regulated at E20. The protein expression of muscle proliferation-related genes were also decreased at E20. Additionally, these results were the same as that in the ERS positive control groups. Taken together, these results indicated that long-term TM during late embryonic period could block the development of duck breast muscle by inhibiting muscle hypertrophy and proliferation, and promoting muscle atrophy at a post-transcriptional level via the activation of ERS.


Assuntos
Patos/embriologia , Desenvolvimento Muscular , Temperatura Ambiente , Animais , Desenvolvimento Embrionário , Estresse do Retículo Endoplasmático , Coração/anatomia & histologia , Coração/embriologia , Hipertrofia , Fígado/anatomia & histologia , Fígado/embriologia , Glândulas Mamárias Animais/embriologia , Músculos/embriologia , Músculos/patologia , Tamanho do Órgão
16.
Asian-Australas J Anim Sci ; 30(7): 920-929, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27660025

RESUMO

OBJECTIVE: The bursa of Fabricius (BF) is a central humoral immune organ belonging specifically to avians. Recent studies had suggested that miRNAs were active regulators involved in the immune processes. This study was to investigate the possible differences of the BF at miRNA level between two genetically disparate duck breeds. METHODS: Using Illumina next-generation sequencing, the miRNAs libraries of ducks were established. RESULTS: The results showed that there were 66 differentially expressed miRNAs and 28 novel miRNAs in bursa. A set of abundant miRNAs (i.e., let-7, miR-146a-5p, miR-21-5p, miR-17~92) which are involved in immunity and disease were detected and the predicted target genes of the novel miRNAs were associated with duck high anti-adversity ability. By gene ontology analysis and enriching KEGG pathway, the targets of differential expressed miRNAs were mainly involved in immunity and disease, supporting that there were differences in the BF immune functions between the two duck breeds. In addition, the metabolic pathway had the maximum enriched target genes and some enriched pathways that were related to cell cycle, protein synthesis, cell proliferation and apoptosis. It indicted that the difference of metabolism may be one of the reasons leading the immune difference between the BF of two duck breeds. CONCLUSION: This data lists the main differences in the BF at miRNAs level between two genetically disparate duck breeds and lays a foundation to carry out molecular assisted breeding of poultry in the future.

17.
Int J Biochem Cell Biol ; 79: 298-307, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27590857

RESUMO

The Akirin gene family normally contains two members that are essential to myoblast differentiation. Noticeably, the avian Akirin gene family comprises only one gene (Akirin2), However, it remains unknown whether avian Akirin gene family still has the function of Akirin1; moreover, it is still unclear whether and how Akirin2 plays a role in myoblast proliferation and differentiation. Interestingly, the unexpected functions of duck Akirin2 were revealed in the present study. The Real-time PCR results showed that between 12 and 48h during the process of duck myoblasts differentiation, the overexpression of Akirin2 did not significantly increase the expression of myogenic regulatory factors. Flow cytometry analysis revealed that the cell cycle transition was accelerated by Akirin2 overexpression. Moreover, the overexpression of Akirin2 did not influence the myotube formation. Strikingly, when duck myoblasts were cultured in the growth medium, the overexpression of Akirin2 significantly enhanced cell viability. Although the expression of cyclin-dependent proteins did not significantly increase after transfection, the expression of the mammalian targets of rapamycin (mTOR) and p70 S6 kinase (p70S6K) increased. Furthermore, the protein expression of phospho-p70S6K (Ser 417) also increased. However, when rapamycin and pEGFP-N1-Akirin2 plasmids were added together to the growth medium, the positive impact of Akirin2 on cell viability and the mRNA expression of mTOR and p70S6K were significantly blocked. Furthermore, the expression of phospho-mTOR (Ser 2448) and phospho-p70S6K (Ser 417) were also blocked. Taken together, these results could suggest that duck Akirin2 could promote myoblast proliferation via the activation of the mTOR/p70S6K signaling pathway.


Assuntos
Diferenciação Celular , Mioblastos/citologia , Proteínas Repressoras/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Animais , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Patos , Regulação da Expressão Gênica/efeitos dos fármacos , Mioblastos/efeitos dos fármacos , Mioblastos/metabolismo , Fatores de Regulação Miogênica/genética , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia , Transcrição Genética/efeitos dos fármacos
18.
DNA Cell Biol ; 35(8): 398-409, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27064738

RESUMO

Myocyte enhancer transcription factor 2D (MEF2D) is an important transcription factor for promoting the growth and development of muscle. CAG repeats have been found in the coding sequence (CDS) of avian MEF2D; however, their functions remain unknown and require further investigation. Here, we examined the characteristics and functional role of MEF2D CAG repeat in duck. The full-length CDS of duck MEF2D was cloned for the first time, and a novel CAG repeat was identified and located in exon 9. Sequence analysis indicated that the protein domains of duck MEF2D are highly conserved relative to other vertebrates, whereas MEF2D CAG repeats with variable repeat numbers are specific to avian species. Furthermore, sequencing has revealed polymorphisms in MEF2D CAG repeat at both DNA and mRNA levels. Four MEF2D CAG repeat genotypes and 10 MEF2D cDNA variants with different CAG repeat numbers were detected in two duck populations. A t-test showed that the expanded CAG repeat generated significantly longer transcription products (p < 0.05). Association analysis demonstrated positive correlations between the expansion of the CAG repeat and five muscle-related traits. By using protein structure prediction, we suggested that the polymorphisms of the CAG repeat affect protein structures within protein domains. Taken together, these findings reveal that duck MEF2D CAG repeat is a potential functional element with polymorphisms and may cause differences in MEF2D function between duck and other vertebrate species.


Assuntos
Proteínas Aviárias/genética , Fatores de Transcrição MEF2/genética , Músculo Esquelético/metabolismo , Polimorfismo Genético , RNA Mensageiro/genética , Repetições de Trinucleotídeos , Sequência de Aminoácidos , Animais , Proteínas Aviárias/química , Proteínas Aviárias/metabolismo , Sequência de Bases , DNA Complementar/genética , DNA Complementar/metabolismo , Patos/genética , Patos/crescimento & desenvolvimento , Éxons , Expressão Gênica , Genótipo , Fatores de Transcrição MEF2/química , Fatores de Transcrição MEF2/metabolismo , Desenvolvimento Muscular/genética , Músculo Esquelético/crescimento & desenvolvimento , Fases de Leitura Aberta , Estrutura Secundária de Proteína , RNA Mensageiro/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA
19.
Artigo em Inglês | MEDLINE | ID: mdl-27040525

RESUMO

RNA-binding motif proteins 24 (Rbm24) and 38 (Rbm38) are known to regulate genes expression in a post-transcriptional way. However, it remains unclear about the similarities and differences between Rbm24 and Rbm38 in terms of their sequence characteristics and expression profiles during myoblast differentiation and skeletal muscle development. In this study, we found that the coding domain sequences (CDSs) of duck Rbm24 and Rbm38 consisted of 678 and 648 nucleotides, respectively. Both of them contain a conserved RNA-recognition motif (RRM). Phylogenetic analysis showed that duck Rbm24 and Rbm38 were clustered with other Aves, nevertheless, avian Rbm24 was clustered with mammalian and reptilian Rbm24; avian Rbm38 was clustered with amphibian and reptilian Rbm38. Real-time PCR results exhibited that during embryonic stage, Rbm24 and Rbm38 in leg and breast muscle increased to their peak (P<0.01) at same time. During postnatal stage, the peak of Rbm24 and Rbm38 in leg were found at W5, while the peak of them in breast was found at W6 (P<0.01). Moreover, a relative high value of Rbm24 and Rbm38 in leg was found at W1 and W3, respectively. Additionally, both Rbm24 and Rbm38 expressed at each stage of duck myoblast differentiation, however, Rbm24 shared similar expression profiles with MEF2C, and Rbm38 shared similar expression profiles with MyoG and MEF2A. Furthermore, hierarchical clustering results were consistent with the preceding findings. These results serve as a foundation for further investigations about similar and different effects of Rbm24 and Rbm38 on myoblast differentiation and skeletal muscle development.


Assuntos
Patos/genética , Regulação da Expressão Gênica , Músculo Esquelético/metabolismo , Mioblastos/metabolismo , Proteínas de Ligação a RNA/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Diferenciação Celular , Clonagem Molecular , Patos/fisiologia , Desenvolvimento Muscular , Músculo Esquelético/fisiologia , Mioblastos/citologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , Análise de Sequência , Homologia de Sequência do Ácido Nucleico
20.
Genet Mol Biol ; 39(1): 151-61, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27007909

RESUMO

As a critical transcription factor, Six1 plays an important role in the regulation of myogenesis and muscle development. However, little is known about its regulatory mechanism associated with muscular protein synthesis. The objective of this study was to investigate the effects of overexpression ofSix1 on the expression of key protein metabolism-related genes in duck myoblasts. Through an experimental model where duck myoblasts were transfected with a pEGFP-duSix1 construct, we found that overexpression of duckSix1 could enhance cell proliferation activity and increase mRNA expression levels of key genes involved in the PI3K/Akt/mTOR signaling pathway, while the expression of FOXO1, MuRF1and MAFbx was not significantly altered, indicating thatSix1 could promote protein synthesis in myoblasts through up-regulating the expression of several related genes. Additionally, in duck myoblasts treated with LY294002 and rapamycin, the specific inhibitors ofPI3K and mTOR, respectively, the overexpression of Six1 could significantly ameliorate inhibitive effects of these inhibitors on protein synthesis. Especially, the mRNA expression levels of mTOR and S6K1 were observed to undergo a visible change, and a significant increase in protein expression of S6K1 was seen. These data suggested that Six1plays an important role in protein synthesis, which may be mainly due to activation of the mTOR signaling pathway.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA