Age-related alteration of proline hydroxylase and collagen-binding heat shock protein (HSP47) expression in human fibroblasts.
Changes in the expression of alpha and beta subunits of proline 4-hydroxylase (PH alpha and PH beta) and HSP47, implicated as a molecular chaperone specific for procollagen processing, were examined in human embryonal fibroblasts in relation to in vitro aging. For this purpose a model with treatments causing the decreased hydroxylation of proline residues in procollagens was used. In cells at a low population doubling level (PDL) induction of PH alpha, PH beta, and HSP47 by depletion of ascorbate or addition of alpha-alpha' dipyridyl could be clearly demonstrated by immunoprecipitation and Northern blotting. In contrast, the induction of PH alpha and HSP47 expression was markedly attenuated in high PDL cells, indicating an age-related decrease in response to procollagen retention in the ER caused by hypohydroxylation of proline residues of procollagens.
Miyaishi
O
O
Institute for Medical Science of Aging, Aichi Medical University, Japan.
Kozaki
K
K
Saga
S
S
Sato
T
T
Hashizume
Y
Y
D000818:Animals; D002460:Cell Line; D016922:Cellular Senescence / Q000502:physiology*; D003094:Collagen / Q000378:metabolism*; D005347:Fibroblasts / Q000378:metabolism; D050958:HSP47 Heat-Shock Proteins; D006360:Heat-Shock Proteins / Q000378:metabolism*; D006801:Humans; D018832:Molecular Chaperones / Q000378:metabolism; D008969:Molecular Sequence Data; D011347:Procollagen / Q000737:chemistry / Q000378:metabolism; D011393:Procollagen-Proline Dioxygenase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D011487:Protein Conformation; D051381:Rats
D050958:HSP47 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D018832:Molecular Chaperones; D011347:Procollagen; C494660:SERPINH1 protein, human; C494662:Serpinh1 protein, rat; D003094:Collagen; D011393:Procollagen-Proline Dioxygenase