Type IV collagenases matrix metalloproteinase-2 ( @entity5780 ) and @entity1235 and their related proteins, @entity5781 , @entity5779 ( @entity5779 ), @entity5783 , and @entity11289 , are expressed during kidney morphogenesis and nephrogenesis, but the renal ontogeny of these proteins is only partially known, and their persistence in the adult remains controversial. Their expression was analyzed from early metanephric stages to adulthood by Western blot semiquantitative analysis; laser confocal microscopy of whole-mount kidneys; and a two-step immunoperoxidase labeling procedure using specific markers of proximal tubule ( @entity20664 ), ascending limb of Henle's loop (Tamm Horsfall protein), and collecting duct (Dolichos biflorus agglutinin lectin). By Western blot, all antigens were detected at day 11.5, peaked at day 16.5, and persisted in the adult at lower levels, although @entity5780 was less modulated. All antigens were expressed in metanephric mesenchyme at embryonic day 11.5 and became concentrated in neural cell adhesion molecule-positive-induced mesenchymal cells at day 12.5. Only @entity5781 and to a lesser extent @entity5780 were detected in the ureter bud. At day 16.5, all antigens predominated in the cytoplasm of the proximal tubule, except @entity5779 , which was mostly expressed in the ascending limb of Henle's loop and distal tubule. During tubule segmentation, components of the @entity1235 system showed both spatial and temporal regulation. The distribution of gelatinases was not strictly superimposable to that of their natural inhibitors TIMP, especially for @entity1235 and @entity5779 . All components persisted in specific segments of the adult renal tubule, where @entity1235 , @entity5780 , and @entity5781 showed an apical expression, suggesting that substrates for these enzymes should be in the tubule lumen or in the apical cell domain and not in the extracellular matrix. These results suggest that a regulated balance of gelatinase activity is required during kidney organogenesis and that gelatinases continue to play a role in adult renal tubule physiology.

Expression of the XXXX system during mouse kidney development and tubule segmentation.

@entity5783 :: ('21858(Tax:10090)', 'Gene') :: ['TIMP2'] @entity5781 :: ('17387(Tax:10090)', 'Gene') :: ['MT1-MMP'] @entity11289 :: ('21859(Tax:10090)', 'Gene') :: ['TIMP3'] @entity5779 :: ('21857(Tax:10090)', 'Gene') :: ['TIMP1', 'tissue inhibitor of metalloproteinases 1'] @entity5780 :: ('17390(Tax:10090)', 'Gene') :: ['MMP2'] @entity20664 :: ('14725(Tax:10090)', 'Gene') :: ['megalin'] @entity1235 :: ('17395(Tax:10090)', 'Gene') :: ['MMP9', 'type IV collagenase']
@entity1235 :: (17395(Tax:10090),Gene) :: ['type IV collagenase']
