What is Virology?

Virology is a new subject formed by the infiltration and fusion of virology and molecular biology with virus as the research object. Specifically, it is a study of the structure and function of the viral genome based on a thorough understanding of the general morphological and structural characteristics of the virus, exploring the viral genome replication, gene expression, and its regulatory mechanisms, thereby revealing viral infection and pathogenic molecules In essence, it provides the scientific basis and scientific basis for the development of viral genetic engineering vaccines and antiviral drugs, as well as the diagnosis, prevention and treatment of viral diseases.

virology

Virology is a new subject formed by the infiltration and fusion of virology and molecular biology with virus as the research object. Specifically, it is a research based on a full understanding of the general morphological and structural characteristics of the virus.

Virology is a science that studies the smallest non-cellular biological virus on the planet, as a class in the earth's biosphere

Viruses are a relatively primitive,

1. Common points:

Like all living things, viruses are a type of

First, the virus is a pathogen that can infect almost all cell-type organisms and cause disease. According to preliminary statistics, 60 ~ 70% of human infectious diseases are caused by virus infection. From common

1)

The formation and development of virology have roughly experienced the following four periods:

1. Discovery period of the virus

2.The chemical age of the virus

3. Cell-level research period

4. Period of molecular virology

1) When a virus is found

Double helix

period

Before the virus was discovered, people began to deal with the virus in a conscious or unconscious process. It is observed that natural phenomena caused by the existence of many viruses cannot be reasonably explained due to the constraints of historical conditions and the level of people's knowledge at the time. Until 1892, when scientist D.Ivanofsky was studying tobacco mosaic disease, he found that the causative factor of tobacco mosaic disease can pass through bacterial filters, but he still believed that the disease was caused by bacteria that produce toxins. Later, in 1898, Dutch scientist Beicherinck repeated D.Ivanofsky's experiment, which proved that tobacco mosaic disease was caused by a filter pathogen. In the same year, German scientists Loeffler and Frosch discovered that FMD pathogens are also filterable. In the following 10 years, more than 10 infectious disease pathogenic viruses (fowl fever virus, yellow fever virus, rabies virus, etc.) have been found, as well as phages and various plant viruses that have been found later.

2) the chemical age of the virus

Tobacco mosaic virus was purified and crystallized by Stanley in the United States for the first time in 1935, which led to a major breakthrough in the understanding of the chemical nature of the virus and opened a broad path for further research on the virus. Then, Bawden et al. Further revealed that the chemical nature of tobacco mosaic virus is not pure protein, but nuclear protein. On this basis, in 1940, Germany's Kausche first observed the rod-like shape of the tobacco mosaic virus using an electron microscope. The application of electron microscopy technology promoted its development from multiple aspects, as the morphological structure of the virus and its role in cells The morphogenetic research within provides an effective means. In short, in this period, although virology has made great progress, it has not yet formed an independent discipline, and its understanding of the nature of virus chemistry is relatively shallow. There is still a lot of debate on the concept of virus.

3) the cellular level of the virus

During this period, virology has made great progress both theoretically and practically, with a unified and clear concept of virus. Gradually formed as an independent discipline, and also laid the foundation for the establishment of molecular virology.

Through the research on the interaction between phage and infected bacteria, clarify the replication cycle of phage; reveal the principle of lysogenic phage induction; prove the infectivity of phage DNA; discover the transduction phenomenon of lysogenic phage and phage, tissue culture technology The establishment of the technology has greatly expanded the scope of virology research and promoted people's understanding of the nature of the virus. At present, the technology has been widely used in the isolation of unknown infectious agents, diagnosis of viral diseases, vaccine production, and basic research on viral infection and replication.

4) Period of molecular virology

Since the establishment of the double-helix structure theory of DNA in 1953, the widespread application of new technologies and methods has made virological research into the development of molecular virology. The 1950s to 1960s were the founding era of molecular biology, and phages and plant viruses have made great contributions to this. Therefore, molecular virology emerged at the historic moment in the development of molecular biology.

virology

At this stage, people are mainly committed to the structure, function, and expression regulation mechanism of the viral genome; the structure, function, and synthesis of viral proteins; the mechanisms of infection, reproduction, and pathogenicity of various viruses; a deeper understanding of the virus and its host Interactions, especially the relationship between tumor viruses and tumorigenesis; continuous exploration of new technologies and methods for the diagnosis, prevention and treatment of viral diseases; understanding of the pathogenic nature of suspected viral diseases for which the etiology has not yet been confirmed; The fruits have been fruitful, specifically in the following aspects.

In 1955 Fraenkel-Conrat completed the in vitro disassembly and reconstruction of the tobacco mosaic virus (TMV) nucleic acid and protein subunits.

1960 Anderer clarified the amino acid sequence of TMV capsid protein subunits

In 1962 Casfar elucidated the icosahedral structure of some viruses, and clarified the composition of nucleocapsid icosahedron.

Retroviral replication

Nathans successfully translated phage RNA in vitro in 1962

In 1965, Spiegelman successfully replicated phage RNA in vitro, thus breaking the traditional concept that the virus must proliferate in vivo. These work played an important role in explaining the reproduction mechanism of DNA viruses and RNA viruses in the future.

In 1970, Baltimore and Temin respectively discovered the reverse transcriptase of the virus, which is an important supplement and development to the central law proposed in 1958.

In 1976, Dueberg discovered that the Rous sarcoma virus contained the oncogene v-src, and that the homologous sequence of the oncogene v-src was also found in the DNA of normal chickens and other vertebrates and invertebrates. Normal genes from cells.

In 1977, Sanger completed the complete sequencing of the phage X174-DNA.

The successful expression of the human interferon gene by Taniguchi in 1979 was a major breakthrough in genetic engineering.

In 1982, Moss and Paoletti successfully used vaccinia virus as a vector to express foreign genes.

virology

In 1983, Montagnier and Gallo isolated human retroviruses (HIV) related to AIDS.

In 1991, Han et al. Introduced the antisense expression sequence of Moloney murine leukemia virus into mouse fertilized eggs, thereby culturing transgenic mice that were successfully resistant to the virus.

The identification of the three-dimensional structure of HIV aspartyl protease in 1995 led to the emergence of inhibitors targeting the active site of viral protease.

In 1996, a Chinese-American cocktail made by He Dayi and others using reverse transcriptase inhibitors and protease inhibitors successfully resisted HIV infection.