Friday, February 6, 2009

Avian influenza virus RNA polymerase PA subunit of the truth was revealed

Author: Anonymous Source: Chicken professional network hit number: 41 Update Time :2009-2-6 8:35:52

Following the August 2008 in "Nature" journal of avian influenza virus RNA thesis, the Chinese Academy of Sciences Institute of Biophysics Research Group led by刘迎芳researcher and academician饶子and the leadership of Nankai University, Tsinghua University and the Biological Physics Laboratory in preliminary work on the basis of further analysis of the RNA polymerase PA subunit of the remaining N-terminal (PAN) of high-resolution crystal structure, and thus the basic completion of influenza virus polymerase PA subunit structural biology research . Their findings clearly revealed the PA protein with endonuclease function. This result reversed the previous reports in the polymerase PB1 subunit complex in the exercise of such a functional inference. February 4, "natural" line once again expressed their latest research results and made a special distribution of news, introduction of this important research results.

It is reported that bird flu virus that contains eight RNA genome segments of negative strand RNA viruses, are known to be 11 kinds of virus encoded proteins. Which, PB1, PB2 and PA, such as three protein subunits of influenza virus important life machine: influenza virus RNA polymerase. In the avian influenza virus replication and infection process, the influenza virus polymerase play a critical role, which is responsible for the exercise of RNA virus genome replication and virus mRNA transcription and other functions. Which, PB2 protein is responsible for capture of host cell mRNA molecules for self-mRNA transcription, PB1 contains the polymerase active center, is an exercise of the virus NA synthesis function of the catalytic subunit, and the PA in the complex has not had a clear function. Study of influenza virus polymerase structure, not only in revealing the role of influenza virus polymerase mechanism has important scientific significance, but also for clinical research and development of antiviral drugs to provide a clear molecular model. However, as in the study of the complex problems of various difficulties, the complex or its subunit composition of the structure has not been revealed.

刘迎芳and饶子and to seize this issue of letting go, and finally a gradual systematic analysis of the H5N1 virus RNA polymerase PA subunit complex of the basic structure. Through the structural analysis, they speculated that the protein may be a new structure of endonuclease. Accordingly, they further develop a series of in vivo and in vitro molecular biology, biochemistry experimental analysis, the results fully confirmed their structural analysis in accordance with the conjecture is correct. The endo-nuclease activity of polymerase complexes will capture the host cell mRNA, by influenza virus polymerase endonuclease cutting, for the virus mRNA transcription. This activity is missing, will result in the virus should not transcribed in the cell mRNA. This conclusion is clearly the first time revealed the PA to participate in virus transcription, an important function of the molecular mechanism, but also the first demonstration of the bird flu virus in the RNA polymerase with the endonuclease function is in the PA subunit, rather than people in the past reported on the PB1 subunit. The study results not only revealed the mechanism of PA function, but also for the relevant pharmaceutical research and development provides a new level of fine structure of atomic platform.

According to the Chinese Academy of Sciences of Life Sciences and Biotechnology Bureau stakeholders introduction, at present, apart from the domestic bird flu, the migratory birds due to other reasons, China's neighboring countries of bird flu can not be ignored. Indonesia is the world's most serious outbreak of avian flu country, as at the end of 2008, the KMT and the occurrence of human infection with 139 cases of bird flu, of which 113 people were killed; Vietnam, second only to Indonesia, as at the end of 2008, a total of 107 cases, of whom 52 deaths. In addition, India, Bangladesh, Vietnam also have outbreaks. Although the countries to strengthen supervision and may speed up the culling of infected poultry in Asia, has been as high as 500 million poultry have died of bird flu or been culled to control the epidemic, H5N1 fatal cases for the past two years to reduce, poultry outbreak countries have reduced in recent years, but the threat of avian flu has always been lingering. Since 2003 after the outbreak, H5N1 has remained at a "minimum level of distribution, but a sudden outbreak of many times" state.

刘迎芳said that in the latest research work, the University of Oxford, Dr. Ervin Fodor and Dr. TaoDeng, National University of Singapore, Dr. RuowenGe also participate in some research work, the United States APS Synchrotron Radiation Center, Professor张荣光in terms of data collection also provides a帮助. In addition, the Chinese Academy of Agricultural Sciences Hualan Chen, Professor Yu Kangzhen provided viral genes.

The study by the National Natural Science Foundation, Ministry of Science and Technology and Chinese Academy of Sciences, support and funding.

No comments: