A 33 kDa protein band is enhanced during long-term adaptation of EUE cells to a hypertonic medium.
A cell line derived from human embryonic epithelium (EUE cells) shows an enhanced expression of a 33 kDa protein when adapted to grow in a hypertonic medium containing 0.246 M NaCl (1.8 x the isotonic concentration). The maximum amount of this protein, followed by SDS-PAGE electrophoresis, was found after 4 days of adaptation; thereafter, the protein band remained fairly constant up to 30 days. When the cells were transferred back to a medium containing 0.137 M NaCl (isotonic medium), the protein pattern reverted to that of control cells. This protein is mainly localized in the cytosol, although a small part is associated with the 150,000 g pellet and needs detergents to be extracted. The molecular weight and the cellular location suggest a possible analogy with the so-called amphitropic proteins, that are known to interact with both the epidermal growth factor receptor and hydrophobic structures, such as the membrane phospholipids and the cytoskeletal components.
Dipartimento di Chimica e Biochimica Medica, University of Milano, Italy.
A
A
Giuliani
A
A
Ferraretto
A M
AM
Fuhrman Conti
L
L
De Grada
A
A
Fraschini
C
C
Pellicciari
M G
MG
Manfredi Romanini
D000222:Adaptation, Physiological; D002460:Cell Line; D016922:Cellular Senescence; D003600:Cytosol / Q000737:chemistry; D004591:Electrophoresis, Polyacrylamide Gel; D004848:Epithelium / Q000737:chemistry / Q000196:embryology / Q000502:physiology; D006801:Humans; D008970:Molecular Weight; D011506:Proteins / Q000187:drug effects / Q000302:isolation & purification*; D012462:Saline Solution, Hypertonic; D013347:Subcellular Fractions / Q000737:chemistry / Q000187:drug effects
D011506:Proteins; D012462:Saline Solution, Hypertonic