This study examined the expression of the anterior gradient-2 （AGR2） protein and Muc5ac protein in the lung tissues of asthmatic mice and the effect of dexamethasone, with an at- tempt to explore the role of AGR2 in...This study examined the expression of the anterior gradient-2 （AGR2） protein and Muc5ac protein in the lung tissues of asthmatic mice and the effect of dexamethasone, with an at- tempt to explore the role of AGR2 in the over-secretion of mucus in the airway. Eighteen BALB/c mice were divided into asthma group, control group and dexamethasone group. In dexamethasone group, dexamethasone was intraperitoneally administered. Expression of AGR2 protein and Muc5ac protein in the murine lung tissues was immunohistochemically detected. IL-13 level was determined in the bronchoalveolar lavage fluid （BALF） by ELISA. The results exhibited that the expression of AGR2 protein in asthma group （0.522±0.041） was significantly higher than that in normal controls （0.361±0.047） （P〈0.01） and bore a positive linear relationship to the expression of Muc5ac protein （r=0.873, P〈0.05） and IL-13 level （r=0.828, P〈0.05）. Expression of AGR2 protein in the dexa- methasone group （0.456±0.049） was significantly lower than that in the asthma group. It was concluded that： （1） the expression of AGR2 protein was significantly higher in asthmatic mice as com- pared with their normal counterparts; （2） the expression was obviously related to the expression of Muc5ac protein and IL-13; （3） dexamethasone could down-regulate the expression of AGR2 protein. Our findings suggested that AGR2 might be involved in the over-secretion of mucus in the airway in asthma.展开更多
A preliminary study on the interaction of G protein (guanine triphosphate binding pro- tein) b1g2 subunits and their coupled components in cell signal transduction was conducted in vitro. The insect cell lines, Sf9 (S...A preliminary study on the interaction of G protein (guanine triphosphate binding pro- tein) b1g2 subunits and their coupled components in cell signal transduction was conducted in vitro. The insect cell lines, Sf9 (Spodoptera frugiperda) and H5 (Trichoplusia ni ) were used to express the recombinant protein Gb1g2. The cell membrane containing Gb1g2 was isolated through affinity chromatography column with Ni-NTA agarose by FPLC method, and the highly purified protein was obtained. The adenylyl cyclase 2 (AC2) activity assay showed that the purified Gb1g2 could signifi-cantly stimulate AC2 activity. The interaction of b1g2 subunits of G protein with the cytoplasmic tail of various mammalian adenylyl cyclases was monitored by BIAcore technology using NTA sensor chip, which relies on the phenomenon of surface plasmon resonance (SPR). The experiments showed the direct binding of Gb1g2 to the cytoplasmic tail C2 domain of AC2. The specific binding domain of AC2 with Gb1g2 was the same as AC2 activity domain which was stimulated by Gb1g2.展开更多
基金supported by the National Natural Science Foundation of China (No. 30900648)
文摘This study examined the expression of the anterior gradient-2 （AGR2） protein and Muc5ac protein in the lung tissues of asthmatic mice and the effect of dexamethasone, with an at- tempt to explore the role of AGR2 in the over-secretion of mucus in the airway. Eighteen BALB/c mice were divided into asthma group, control group and dexamethasone group. In dexamethasone group, dexamethasone was intraperitoneally administered. Expression of AGR2 protein and Muc5ac protein in the murine lung tissues was immunohistochemically detected. IL-13 level was determined in the bronchoalveolar lavage fluid （BALF） by ELISA. The results exhibited that the expression of AGR2 protein in asthma group （0.522±0.041） was significantly higher than that in normal controls （0.361±0.047） （P〈0.01） and bore a positive linear relationship to the expression of Muc5ac protein （r=0.873, P〈0.05） and IL-13 level （r=0.828, P〈0.05）. Expression of AGR2 protein in the dexa- methasone group （0.456±0.049） was significantly lower than that in the asthma group. It was concluded that： （1） the expression of AGR2 protein was significantly higher in asthmatic mice as com- pared with their normal counterparts; （2） the expression was obviously related to the expression of Muc5ac protein and IL-13; （3） dexamethasone could down-regulate the expression of AGR2 protein. Our findings suggested that AGR2 might be involved in the over-secretion of mucus in the airway in asthma.
基金This work was sup-ported by the National Natural Science Foundation of China (Grant No. 30170615) and National Major Basis Study Develop-mental Plan 973 Project (TG2000016208).
文摘A preliminary study on the interaction of G protein (guanine triphosphate binding pro- tein) b1g2 subunits and their coupled components in cell signal transduction was conducted in vitro. The insect cell lines, Sf9 (Spodoptera frugiperda) and H5 (Trichoplusia ni ) were used to express the recombinant protein Gb1g2. The cell membrane containing Gb1g2 was isolated through affinity chromatography column with Ni-NTA agarose by FPLC method, and the highly purified protein was obtained. The adenylyl cyclase 2 (AC2) activity assay showed that the purified Gb1g2 could signifi-cantly stimulate AC2 activity. The interaction of b1g2 subunits of G protein with the cytoplasmic tail of various mammalian adenylyl cyclases was monitored by BIAcore technology using NTA sensor chip, which relies on the phenomenon of surface plasmon resonance (SPR). The experiments showed the direct binding of Gb1g2 to the cytoplasmic tail C2 domain of AC2. The specific binding domain of AC2 with Gb1g2 was the same as AC2 activity domain which was stimulated by Gb1g2.
