Matrix metalloproteinases (MMPs) are a family of extracellular proteases capable of degrading various proteinaceous components of the extracellular matrix (ECM).They have been implicated to play important roles in a n...Matrix metalloproteinases (MMPs) are a family of extracellular proteases capable of degrading various proteinaceous components of the extracellular matrix (ECM).They have been implicated to play important roles in a number of developmental and pathological processes, such as tumor metastasis and inflammation. Relatively few studies have been carried out to investigate the function of MMPs during postembryonic organ-development. Using Xenopus laevis development as a model system, we demonstrate here that three MMPs, stromelysin-3 (ST3),collagenases-3 (Col3), and Col4, have distinct spatial and temporal expression profiles during metamorphosis as the tadpole transforms into a frog. In situ hybridizations reveal a tight, but distinct, association of individual MMPs with tissue remodeling in the tail and intestine during metamorphosis. In particular, ST3 expression is strongly correlated with apoptosis in both organs as demonstrated by analyses of serial sections with in situ hybridization for ST3 mRNA and TUNEL (terminal deoxyribonucleotidyl transferase-mediated dUTP-biotin nick end labeling) for apoptosis, respectively. On the other hand, Col3 and Col4 MMPs in Xenopus laevis development are present in regions where extensive connective tissue remodeling take place. These results indicate that ST3 is likely to play a role in ECM-remodeling that facilitateapoptotic tissue remodeling or resorption while Col3 and Col4 appear to participate in connective tissue degradation during development.展开更多
Membrane proteins are involved in various critical biological processes,and studying membrane proteins represents a major challenge in protein biochemistry.As shown by both structural and functional studies,the membra...Membrane proteins are involved in various critical biological processes,and studying membrane proteins represents a major challenge in protein biochemistry.As shown by both structural and functional studies,the membrane environment plays an essential role for membrane proteins.In vitro studies are reliant on the successful reconstitution of membrane proteins.This review describes the interaction between detergents and lipids that aids the understanding of the reconstitution processes.Then the techniques of detergent removal and a few useful techniques to refine the formed proteoliposomes are reviewed.Finally the applications of reconstitution techniques to study membrane proteins involved in Ca2+ signaling are summarized.展开更多
文摘Matrix metalloproteinases (MMPs) are a family of extracellular proteases capable of degrading various proteinaceous components of the extracellular matrix (ECM).They have been implicated to play important roles in a number of developmental and pathological processes, such as tumor metastasis and inflammation. Relatively few studies have been carried out to investigate the function of MMPs during postembryonic organ-development. Using Xenopus laevis development as a model system, we demonstrate here that three MMPs, stromelysin-3 (ST3),collagenases-3 (Col3), and Col4, have distinct spatial and temporal expression profiles during metamorphosis as the tadpole transforms into a frog. In situ hybridizations reveal a tight, but distinct, association of individual MMPs with tissue remodeling in the tail and intestine during metamorphosis. In particular, ST3 expression is strongly correlated with apoptosis in both organs as demonstrated by analyses of serial sections with in situ hybridization for ST3 mRNA and TUNEL (terminal deoxyribonucleotidyl transferase-mediated dUTP-biotin nick end labeling) for apoptosis, respectively. On the other hand, Col3 and Col4 MMPs in Xenopus laevis development are present in regions where extensive connective tissue remodeling take place. These results indicate that ST3 is likely to play a role in ECM-remodeling that facilitateapoptotic tissue remodeling or resorption while Col3 and Col4 appear to participate in connective tissue degradation during development.
基金supported by US National Institutes of Health(R01GM096458)to Wang LiGuo
文摘Membrane proteins are involved in various critical biological processes,and studying membrane proteins represents a major challenge in protein biochemistry.As shown by both structural and functional studies,the membrane environment plays an essential role for membrane proteins.In vitro studies are reliant on the successful reconstitution of membrane proteins.This review describes the interaction between detergents and lipids that aids the understanding of the reconstitution processes.Then the techniques of detergent removal and a few useful techniques to refine the formed proteoliposomes are reviewed.Finally the applications of reconstitution techniques to study membrane proteins involved in Ca2+ signaling are summarized.
