C1q is the first subcomponent of classical pathway in the complement system and a major link between innate and acquired immunities. The globular （gC1q） domain similar with C1q was also found in many non-complement ...C1q is the first subcomponent of classical pathway in the complement system and a major link between innate and acquired immunities. The globular （gC1q） domain similar with C1q was also found in many non-complement C1q-domain-containing （C1qDC） proteins which have similar crystal structure to that of the multifunctional tumor necrosis factor （TNF） ligand family, and also have diverse functions. In this study, we identified a total of 52 independent gene sequences encoding C1q-domain-containing proteins through comprehensive searches of zebrafish genome, cDNA and EST databases. In comparison to 31 orthologous genes in human and different numbers in other species, a significant selective pressure was suggested during vertebrate evolution. Domain organization of C1q-domain-containing （C1qDC） proteins mainly includes a leading signal peptide, a collagen-like region of variable length, and a C-terminal C1q domain. There are 11 highly conserved residues within the C1q domain, among which 2 are invariant within the zebrafish gene set. A more extensive database searches also revealed homologous C1qDC proteins in other vertebrates, invertebrates and even bacterium, but no homologous sequences for encoding C1qDC proteins were found in many species that have a more recent evolutionary history with zebrafish. Therefore, further studies on C1q-domain-containing genes among different species will help us understand evolutionary mechanism of innate and acquired immunities.展开更多
An imaging riometer with 8×8 antenna array was installed successfully at Zhongshan Station, Antarctica in January 1997.The structure and working principle of the instrument are described. The first set of observ...An imaging riometer with 8×8 antenna array was installed successfully at Zhongshan Station, Antarctica in January 1997.The structure and working principle of the instrument are described. The first set of observation data is analyzed and the quiet day curve(QDC) are deduced. Preliminary results show that cosmic noise absorption is very different between night side and magnetic noon. In night side, there are often short duration impulsive absorption events with a large absorption area in the northern side of the station, stretching in an east west direction. In magnetic noon the absorption event is continuous, which lasts for more than 1 h with the absorption area strengthening in the northern and southern sides and weakening in the middle. It is thought that the absorption is caused by aurora particle precipitation in night side and by soft particle precipitation or convection in cusp at magnetic noon.展开更多
基金Acknowledgements This work was supported by the National Major Basic Research Program （No. 2004CB117401）；by the National Natural Science Foundation of China （No. 90408013）.
文摘C1q is the first subcomponent of classical pathway in the complement system and a major link between innate and acquired immunities. The globular （gC1q） domain similar with C1q was also found in many non-complement C1q-domain-containing （C1qDC） proteins which have similar crystal structure to that of the multifunctional tumor necrosis factor （TNF） ligand family, and also have diverse functions. In this study, we identified a total of 52 independent gene sequences encoding C1q-domain-containing proteins through comprehensive searches of zebrafish genome, cDNA and EST databases. In comparison to 31 orthologous genes in human and different numbers in other species, a significant selective pressure was suggested during vertebrate evolution. Domain organization of C1q-domain-containing （C1qDC） proteins mainly includes a leading signal peptide, a collagen-like region of variable length, and a C-terminal C1q domain. There are 11 highly conserved residues within the C1q domain, among which 2 are invariant within the zebrafish gene set. A more extensive database searches also revealed homologous C1qDC proteins in other vertebrates, invertebrates and even bacterium, but no homologous sequences for encoding C1qDC proteins were found in many species that have a more recent evolutionary history with zebrafish. Therefore, further studies on C1q-domain-containing genes among different species will help us understand evolutionary mechanism of innate and acquired immunities.
文摘An imaging riometer with 8×8 antenna array was installed successfully at Zhongshan Station, Antarctica in January 1997.The structure and working principle of the instrument are described. The first set of observation data is analyzed and the quiet day curve(QDC) are deduced. Preliminary results show that cosmic noise absorption is very different between night side and magnetic noon. In night side, there are often short duration impulsive absorption events with a large absorption area in the northern side of the station, stretching in an east west direction. In magnetic noon the absorption event is continuous, which lasts for more than 1 h with the absorption area strengthening in the northern and southern sides and weakening in the middle. It is thought that the absorption is caused by aurora particle precipitation in night side and by soft particle precipitation or convection in cusp at magnetic noon.
