RESUMO
Pathological cardiac hypertrophy is the primary cause of heart failure, yet its underlying mechanisms remain incompletely understood. Transmembrane protein 100 (TMEM100) plays a role in various disorders, such as nervous system disease, pain and tumorigenesis, but its function in pathological cardiac hypertrophy is still unknown. In this study, we observed that TMEM100 is upregulated in cardiac hypertrophy. Functional investigations have shown that adeno-associated virus 9 (AAV9) mediated-TMEM100 overexpression mice attenuates transverse aortic constriction (TAC)-induced cardiac hypertrophy, including cardiomyocyte enlargement, cardiac fibrosis, and impaired heart structure and function. We subsequently demonstrated that adenoviral TMEM100 (AdTMEM100) mitigates phenylephrine (PE)-induced cardiomyocyte hypertrophy and downregulates the expression of cardiac hypertrophic markers in vitro, whereas TMEM100 knockdown exacerbates cardiomyocyte hypertrophy. The RNA sequences of the AdTMEM100 group and control group revealed that TMEM100 was involved in oxidative stress and the MAPK signaling pathway after PE stimulation. Mechanistically, we revealed that the transmembrane domain of TMEM100 (amino acids 53-75 and 85-107) directly interacts with the C-terminal region of TAK1 (amino acids 1-300) and inhibits the phosphorylation of TAK1 and its downstream molecules JNK and p38. TAK1-binding-defective TMEM100 failed to inhibit the activation of the TAK1-JNK/p38 pathway. Finally, the application of a TAK1 inhibitor (iTAK1) revealed that TAK1 is necessary for TMEM100-mediated cardiac hypertrophy. In summary, TMEM100 protects against pathological cardiac hypertrophy through the TAK1-JNK/p38 pathway and may serve as a promising target for the treatment of cardiac hypertrophy.
Assuntos
Cardiomegalia , MAP Quinase Quinase Quinases , Proteínas de Membrana , Miócitos Cardíacos , Animais , Cardiomegalia/genética , Cardiomegalia/metabolismo , Cardiomegalia/patologia , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , MAP Quinase Quinase Quinases/metabolismo , MAP Quinase Quinase Quinases/genética , Camundongos , Camundongos Endogâmicos C57BL , Masculino , Progressão da Doença , Humanos , Fenilefrina/farmacologia , Sistema de Sinalização das MAP Quinases , Estresse OxidativoRESUMO
To analyze quality standards of cattle bile and sheep bile, and to discuss the related problems in the standards. The results showed that physical forms of the related medicinal materials of cattle bile and sheep bile were chaotic, and the technical methods adopted in the quality standards were generally backward. In addition, there were still problems that some medicinal material standards lacked necessary test items, which were especially obvious in the relevant medicinal material standards of sheep bile and brought difficulties to quality evaluation and control. We suggest that physical forms of cattle bile and sheep bile in quality standards should be determined, and inspection items should be completed. Based on mainstream analytical technology, some technical methods of these standards should be improved.
Assuntos
Bile , Esteroides , Animais , Bovinos , Padrões de Referência , OvinosRESUMO
Cytochrome P450 monooxygenases (CYPs) play essential physiological functions in insects. CYP303A1 is highly conserved in insect species studied to date, and shows an indispensable role for adult eclosion in both Locusta migratoria and Drosophila melanogaster. However, how CYP303A1 is regulated to control insect developmental processes remains uninvestigated. In this study, we discovered functional binding sites for miR-184 in the coding sequence of LmCYP303A1. The luciferase reporter assay showed that miR-184 could target LmCYP303A1 and regulate its expression in vitro. Furthermore, overexpression of miR-184 through microinjection of agomir to locusts reduced the transcripts of LmCYP303A1 and led to abnormal molting, which is similar to the phenotype of silencing LmCYP303A1 by direct injection of dsLmCYP303A1 to locusts. Meanwhile, down-regulation of miR-184 by injection of antagomir increased the LmCYP303A1 transcript and caused molting defects. These findings suggested that miR-184 could target LmCYP303A1 to regulate the molting process in L. migratoria, which might be considered as a novel target for pest control.
Assuntos
Locusta migratoria , MicroRNAs/metabolismo , Muda/genética , Animais , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Regulação da Expressão Gênica no Desenvolvimento , Locusta migratoria/genética , Locusta migratoria/metabolismo , MicroRNAs/genéticaRESUMO
SnRK2 (sucrose non-fermenting 1-related protein kinases 2) represents a unique family of protein kinase in regulating signaling transduction in plants. Although the regulatory mechanisms of SnRK2 have been well demonstrated in Arabidopsis thaliana, their functions in maize are still unknown. In our study, we cloned an SnRK2 gene from maize, ZmSAPK8, which encoded a putative homolog of the rice SAPK8 protein. ZmSAPK8 had two copies in the maize genome and harbored eight introns in its coding region. We demonstrated that ZmSAPK8 expressed differentially in various organs of maize plants and was up-regulated by high-salinity and drought treatment. A green fluorescent protein (GFP)-tagged ZmSAPK8 showed subcellular localization in the cell membrane, cytoplasm and nucleus. In vitro kinase assays indicated that ZmSAPK8 preferred Mn(2+) to Mg(2+) as cofactor for phosphorylation, and Ser-182 and Thr-183 in activation loop was important for its activity. Heterologous overexpression of ZmSAPK8 in Arabidopsis could significantly strengthen tolerance to salt stress. Under salt treatment, ZmSAPK8-overexpressed transgenic plants exhibited higher germination rate and proline content, low electrolyte leakage and higher survival rate than wild type. Further analysis indicated that transgenic plants showed increased transcription of the stress-related genes, RD29A, RD29B, RAB18, ABI1, DREB2A and P5CS1, under high-salinity conditions. The results demonstrated that ZmSAPK8 was involved in diverse stress signal transduction. Moreover, no obvious adverse effects on growth and development in the ZmSAPK8-overexpressed transgenic plants implied that ZmSAPK8 was potentially useful in transgenic breeding to improve salt tolerance in crops.
Assuntos
Arabidopsis/genética , Proteínas Serina-Treonina Quinases/genética , Tolerância ao Sal , Zea mays/genética , Sequência de Aminoácidos , Arabidopsis/efeitos dos fármacos , Arabidopsis/metabolismo , Arabidopsis/fisiologia , Clonagem Molecular , DNA Complementar/genética , Eletrólitos/metabolismo , Ativação Enzimática , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Germinação , Manganês/metabolismo , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Fosforilação , Filogenia , Plantas Geneticamente Modificadas/efeitos dos fármacos , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Plantas Geneticamente Modificadas/fisiologia , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Transdução de Sinais , Cloreto de Sódio/farmacologia , Estresse Fisiológico , Transcrição Gênica , Regulação para Cima , Zea mays/efeitos dos fármacos , Zea mays/metabolismoRESUMO
Taking three sand-fixing plantations Hedysarum scoparium and Calligonum mongolicum, Haloxylon ammodendron on the oasis verges in northeast Ulanbuhe desert irrigated by Huanghe River as test objects, the multi-species and multi-scale patterns and the species associations of the plantations were investigated by contiguous quadrats transects method, with the natural vegetation nearby as the control. The results showed that 74.29% of the natural vegetation was dominated by single species pattern of Artemisia ordosica, and 24. 99% was dominated by single species pattern of Nitraria tangutorum. The sand-fixing plantations gradually became close-to-natural vegetation. Compared with natural vegetation, the sand-fixing plantations had higher pattern intensity, and played important role in sand-fixing and in accelerating the regeneration and succession of natural sand-fixing plants. However, with the succession, artificially planted shrubs would decline, while natural plants would be dominant. Therefore, it should be better to make use of the native dominated species in sand-fixing engineering. Under the almost same conditions, pattern scale was highly correlated with the characters and the associations of dominated species. The species association was correlated with the patch scale and species composition, as well as the species contribution to the patch.
Assuntos
Conservação dos Recursos Naturais , Clima Desértico , Ecossistema , Desenvolvimento Vegetal , China , Plantas/classificação , Especificidade da EspécieRESUMO
Maize female organs are sensitive to drought stress, leading to reproductive failure and yield reduction. In the present study gene expression profiles of ears and silks of maize at the flowering stage under drought stress were investigated. From 1920 white positive clones of a forward suppression subtractive hybridization (SSH) library, 1439 available sequences of expression sequence tags (ESTs) were obtained, resulting in 361 unique ESTs after assembling. Data analysis showed that 218 of the unique ESTs had significant protein homology by BLASTX in UNIPROT database. Totally 99 uniESTs were found in TIGR maize gene indices and nr database by BLASTN, while 44 uniESTs were not found to have homologous nucleic acid sequences and putatively classified as "maize-specific" uniESTs. The 218 cDNAs with significant protein homology were sorted into 13 groups according to the functional categories of the Arabidopsis proteins. Among those genes, the genes associated with the metabolisms were the largest group (account for 27%), and the genes related to protein synthesis, protein fate, transcription, cell cycle and DNA processing accounted for 16, 10, 10 and 9%, respectively. After analysis of macroarray data and real-time quantitative polymerase chain reaction (PCR), it was found that 160 of the 218 homologous protein uniESTs were up-regulated genes in the ears, 129 in the silks, and 125 in both of the tissues. The present work provided a valuable starting point for further elucidation of the roles played by these genes/gene products in drought tolerance in maize.