RESUMO
BACKGROUND: Selenium is an essential trace element, and selenocysteine (Sec, U) is its predominant form in vivo. Proteins that contain Sec are selenoproteins, whose special structural features include not only the TGA codon encoding Sec but also the SECIS element in mRNA and the conservation of the Sec-flanking region. These unique features have led to the development of a series of bioinformatics methods to predict and research selenoprotein genes. There have been some studies and reports on the evolution and distribution of selenoprotein genes in prokaryotes and multicellular eukaryotes, but the systematic analysis of single-cell eukaryotes, especially algae, has been very limited. RESULTS: In this study, we predicted selenoprotein genes in 137 species of algae by using a program we previously developed. More than 1000 selenoprotein genes were obtained. A database website was built to record these algae selenoprotein genes ( www.selenoprotein.com ). These genes belong to 42 selenoprotein families, including three novel selenoprotein gene families. CONCLUSIONS: This study reveals the primordial state of the eukaryotic selenoproteome. It is an important clue to explore the significance of selenium for primordial eukaryotes and to determine the complete evolutionary spectrum of selenoproteins in all life forms.
Assuntos
Eucariotos , Selênio , Selenoproteínas , Códon de Terminação , Eucariotos/genética , Eucariotos/metabolismo , Evolução Molecular , Proteoma , Selenocisteína , Selenoproteínas/genética , Selenoproteínas/metabolismoAssuntos
Dor no Peito/diagnóstico , Estenose Coronária/diagnóstico , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Adulto , Idoso , Processamento Alternativo , Biomarcadores/sangue , Dor no Peito/sangue , Dor no Peito/etiologia , Angiografia Coronária , Estenose Coronária/sangue , Estenose Coronária/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Isoformas de Proteínas/sangue , Estudos Retrospectivos , Índice de Gravidade de DoençaRESUMO
PURPOSE: The purpose of this study is to examine the role of the double-stranded RNA (dsRNA) activated Toll-interleukin-1 receptor domain-containing adaptor inducing interferon ß (TRIF) signal pathway in triggering apoptosis in hepatocellular carcinoma (HCC) cells. MATERIALS AND METHODS: First, siRNA targeted autophagy-related gene LC3 (pU6H1-LC3 siRNA and siLC3) and a dsRNA used as a Toll-like receptor 3 (TLR3) ligand was constructed and synthesized, respectively. Then, a human HCC cell line was transfected with dsRNA, siLC3, and cotransfected with siLC3 and dsRNA (siLC3+dsRNA), respectively. Finally, quantification real-time polymerase chain reaction, western blotting, and immunofluorescence staining were used in the HCC line (SMMC7721), and MTT assay, flow cytometry, terminal deoxynucleotidyl transferase-mediated dUTP nick-end-labeling, and transmission electron microscopy were used in an HCC xenograft model of nude mice. Human umbilical vein endothelial cell tube forming assay, color Doppler ultrasonographic flow image examination, and CD34-positive microvessel density were used in vitro and in vivo. RESULTS: Compared with untreated cells, the protein and mRNA expression of TLR3 and TRIF was up-regulated, in order, siLC3+dsRNA, dsRNA, and siLC3. Expression of LC3 was obviously down-regulated and the autophagosomes were significantly decreased in siLC3+dsRNA and siLC3, whereas in dsRNA (p < 0.05). LC3 and TRIF colocation was observed in HepG2 cells. Decreased cell viability, increased apoptosis, decrease in xenograft tumor volume, and angiogenesis potential were also observed in order (p < 0.05). CONCLUSION: Suppression of intracellular autophagy resulted in decreased degradation of TRIF protein, which can promote triggering of apoptosis by the TLR3-TRIF pathway. dsRNA and siLC3 could play anticancer roles in coordination.
