T. Kumazaki et al., EXPRESSION OF ENDOTHELIN, FIBRONECTIN, AND MORTALIN AS AGING AND MORTALITY MARKERS, Experimental gerontology, 32(1-2), 1997, pp. 95-103
Studies on fibronectin, endothelin-l, and mortalin from our laboratory
are reviewed here. Fibronectin expression has been analyzed as upregu
lated during in vitro serial passaging of human fetal lung and neonata
l foreskin fibroblasts as well as umbilical vein endothelial cells. In
vivo aging of skin fibroblasts, as well as aortic endothelial cells,
are also accompanied by upregulation of fibronectin expression. Fibron
ectin promoter binding proteins from young and old cell nuclear extrac
ts were further explored by gel retardation assay. Preliminary analyse
s have detected age-related differential binding activities with respe
ct to AP-1, CRES, TFIID, CTF, and AP-2 regions, whereas Spl binding pr
oteins remain unaltered. Endothelin-l expression is also seen as upreg
ulated during in vitro and in vivo aging of endothelial cells. This ca
n contribute to the hypertension commonly observed in elderly patients
. Mortalin, a novel member of hsp70 family of proteins, was initially
identified by virtue of its association with a cellular mortal phenoty
pe. Subsequently, normal cells and the ones with an immortal phenotype
have been found to have differential subcellular localization of this
protein. Antiproliferative activity of this protein in normal cells a
nd the deregulation of expression in transformed cells is observed whi
ch suggests the association of mortalin in pathways that determine cel
lular divisional phenotype. Copyright (C) 1997 Elsevier Science Inc.