RESUMEN
BACKGROUND: The protective role of Prdx6 on rat corneal tissue against ultraviolet B injury in vivo has been confirmed previously. We further investigated the function and molecular mechanism of Prdx6 in human corneal epithelial cells under ultraviolet B radiation. METHODS: The experimental groups were designed as follows: (1) Prdx6 RNAi, (2) Prdx6 RNAi + ultraviolet B radiation, (3) normal human corneal epithelial cells, (4) normal human corneal epithelial cells + ultraviolet B radiation, (5) wild-type Prdx6 overexpression, (6) wild-type Prdx6 overexpression + ultraviolet B radiation, (7) mutant-type Prdx6 overexpression, and (8) mutant-type Prdx6 overexpression + ultraviolet B radiation. The cell survival rate was detected by a Thiazolyl Blue Tetrazolium Bromide assay. Apoptosis, reactive oxygen species, and malondialdehyde were detected with a commercial kit. Gene expression was detected by real-time polymerase chain reaction. RESULTS: We found the following results. (1) Compared to normal cells, the survival rates were 32%, 87%, and 58% under ultraviolet B radiation in the Prdx6 interference, wild-type overexpression, and mutant-type overexpression groups, respectively. The survival rates were decreased to 50% at 24 h and 31% at 48 h when the phospholipase A2 activity of Prdx6 was inhibited after ultraviolet B radiation. (2) Apoptosis, reactive oxygen species content, and malondialdehyde levels were increased when Prdx6 was downregulated. This phenomenon became more severe under ultraviolet B radiation. (3) The expression levels of apoptosis-related and antioxidant genes all changed along with the changes in expression of Prdx6. CONCLUSION: (1) Both peroxidase and phospholipase A2 activities of Prdx6 are crucial for its protective role in corneal tissue. (2) Downregulated expression of Prdx6 resulted in high endoplasmic reticulum stress. (3) Apoptosis in human corneal epithelial cells with downregulated Prdx6 coupled with ultraviolet B radiation was related to the pathways of DNA damage and the death receptor. (4) Low levels of antioxidants are sufficient for maintaining homeostasis in human corneal epithelial cells without external stimuli. Under the condition that Prdx6 was downregulated, human corneal epithelial cells were more sensitive to ultraviolet B radiation.
Asunto(s)
Epitelio Corneal/efectos de la radiación , Regulación de la Expresión Génica/fisiología , Peroxiredoxina VI/genética , Traumatismos Experimentales por Radiación/prevención & control , Rayos Ultravioleta/efectos adversos , Animales , Apoptosis , Supervivencia Celular , Colorantes/metabolismo , Epitelio Corneal/metabolismo , Epitelio Corneal/patología , Humanos , Malondialdehído/metabolismo , Peroxidasa/metabolismo , Fosfolipasas A2/metabolismo , Plásmidos , ARN Mensajero/genética , Traumatismos Experimentales por Radiación/metabolismo , Traumatismos Experimentales por Radiación/patología , Especies Reactivas de Oxígeno/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Sales de Tetrazolio/metabolismo , Tiazoles/metabolismo , TransfecciónRESUMEN
The complete mitochondrial genome of Centropus sinensis is determined in this study. The circle genome with the 17 159 bp total length contained 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes, and 1 control region. Phylogenetic tree shows that C. sinensis was sister to C. unirufus. The mitogenome of C. sinensis will contribute to researches of mitogenomic evolution, phylogenetic relationship, and conservation genetics.
Asunto(s)
Aves/genética , Genoma Mitocondrial/genética , Animales , Filogenia , ARN Ribosómico/genética , ARN de Transferencia/genéticaRESUMEN
The complete mitochondrial genome of Halcyon smyrnensis was determined in this study. The mitogenomic length of Halcyon smyrnensis was 17 318 bp, including 13 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes and one control region. Phylogenetic analyses show that H. leucocephala, H. pileata and H. smyrnensis congregated together, and our sample was sister to H. pileata.
