The Mechanism Of Lysosome Depletion Induced By The Highly Pathogenic Avian Influenza Virus H5N1Infection

The highly pathogenic influenza A virus subtype H5N1has caused extensive outbreaks and brought catastrophic damage in domestic poultry mainly in parts of Asia, nearly60%of patients known to be infected with the H5N1virus dying from it. Recently some research teams reported that H5N1virus might mutate or reassort into a new strain capable of human-to-human transmission efficiently, so the H5N1virus would be a serious threat to human life and health in future. Influenza virus has evolved various mechanisms that enable it to invade host cells and subvert the host cell machinery for its own replication, at the same time it also disrupts the cellular antiviral response through protein-protein interaction. Although we have known much about the influenza virus, but still we couldn't illustrate the detail pathogenic mechanisms of H5N1avian influenza virus, especially the role of lysosome in the process of influenza virus infection.In this study we found that the lysosome depletion could be induced by the H5N1virus infection in the A549cells, and the damage of lysosomal membrane integrity and its normal function might contribute to the pathogenesis of avian influenza virus. Further studies showed that the H5N1virus protein neuraminidase(NA) directly attributed to the degradation of the lysosomal membrane glycoprotein, and thus led to lysosomal puncture and dysfunction. Besides, this study also found that NA inhibitors such as Oseltamivir and Zanamivir could alleviate lysosomal membrane protein degradation induced by virus NA, therefore the inhibition of NA activity during the influenza A virus infection might be another mechanism of NA inhibitors. At last we also found that interference of lysosome function might be a common phenomenon of influenza A virus infection.The lysosome dysfunction induced by the H5N1virus may be a key pathogenic mechanism of H5N1virus, contributing to the high viral load in the infected lungs or cells and immunity suppression observed in the infected patients. The results of this study may be applicable for the antiviral drug design in future.Association analysis of the phenotype and genotype changes of expeditioners responsed to the extreme environment at Antarctic Dome A Antarctic Dome A is famous for high altitude, hypoxia, low temperature, bitter wind, as well as nearly absolute isolation. This harsh natural and social environment enables Dome A also to be known as the one of "inaccessible poles". However, Dome A is the best place for some scientific research such as climatology etc.. In2008, China set up a new scientific research station called "Kunlun Station" at the Dome A, and every year a scientific expedition team will get to the Dome A for routine scientific research. Long-time living and working in the Antarctic, the expeditioners often suffered from serious psychological responses such as impulse, irritability, depression, insomnia, fatigue, lags in response, cognition impairment etc., Those responses are also known as Antarctic syndrome. At the same time, the environment of plateau and low-oxygen can cause pulmonary edema, cerebral edema in some expeditioners, so learning the variety of physiological and psychological changes induced by the extreme harsh environment of Dome A is important for the protection of these expeditioners.To investigate how the extreme environment at Antarctic Dome A affected scientific expeditioners and prevented them from Antarctic syndrome, we studied the24th Chinese Antarctic Dome A expedition team, by analyzing the expeditioners'physical function and gene expression profiles of peripheral white blood leukocytes at Dome A comparing with start in Shanghai. After measuring150kinds of physical, psychological parameters, we found that these members at Dome A showed a typical plateau physiological stress response with significantly increased male sex hormones, accompanied with psychological and emotional abnormal changes. We also found that sex hormones were evidently correlation with emotional changes, cerebral oxygen delivery as well as cardiac function. In the enrichment analysis we could get some GO terms such as nervous system development, spermatogenesis, and response to drugs, indicating that the differential gene expression of the peripheral white blood cells could correlate with some phenotype changes in some degree.In this study, a comprehensive analysis of the physiological and psychological response to the Dome A extreme environments might be valuable for the screening, training and psychological counseling of the expeditioners in future.Massive Expression and Purification of HIV gp160proteinThe human immunodeficiency virus (HIV) infection can cause acquired immunodeficiency syndrome (AIDS), which often causes secondary infection and death because of immunodeficiency. Currently more than30million people are living with HIV around the world. More seriously there are about3million new HIV infections each year. However, there is no effective vaccine or drugs for prevention and therapy by now. HIV structure protein gp160that makes up the envelope membrane of the virus, which also plays a crucial role in the virus entry into host cells and mediates neutralizing antibodies, there are several virus entry inhibitors that target gp160protein with certain effect in clinical therapy, but the lack of the gp160protein crystal structure hinders the design and development of new and more effective viral entry inhibitors. The gp160has been listed by the journal Nature in2009as one of the most ten desirable proteins to obtain crystal structure in biology. And the expression and purification of gp160protein is very important for the crystal structure analysis.In this study, we took advantage of the protein expression and purification technology in our laboratory to get the gp160protein. Firstly we optimized the cDNA codon sequence with human preferred codon usage, cloned the modified gene into our eukaryotic expression vector and then expressed the gp160in human293cell line utilizing the latest Wave large-scale cell culture system. At last, we successfully expressed and purified high amount of gp160protein, we also found that ligation of T4F trimerization with gp160ends would increase the proportion of trimer in the gp160mixture. The purified proteins enabled us to generate gp160antibodies and analyze its crystal structure. In addition, this study provided a good platform to express and purify other proteins.