Stimulation in vitro of rabbit erythrocyte cytosol phospholipid-dependent protein kinase activity. A novel action of thyroid hormone.
L-Thyroxine (T4) and 3,3',5-L-triiodothyronine (T3) at 10(-10) M stimulated phospholipid- and Ca2+-dependent protein kinase activity in rabbit red cell cytosol in vitro by 151 and 176%, respectively. Kinase of 30-fold greater specific activity, developed with 0.4 mM NaCl from cytosol applied to DEAE-cellulose, was also stimulated up to 2-fold by thyroid hormone. Hormone enhancement of kinase activity occurred after 60 min of incubation at 37 degrees C prior to enzyme assay. Thyroid hormone analogues triiodothyroacetic acid, 3,5-dimethyl-3'-isopropyl-L-thyronine, D-T3, D-T4, and 3,3',5'-L-triiodothyronine (reverse T3) were inactive. These results support a role for thyroid hormone endogenously in regulation of phospholipid-dependent protein kinase activity.
Lawrence
W D
WD
Department of Medicine, State University of New York, Buffalo.
Schoenl
M
M
Davis
P J
PJ
D000818:Animals; D003600:Cytosol / Q000201:enzymology*; D004912:Erythrocytes / Q000201:enzymology*; D005260:Female; D006454:Hemoglobins; D006657:Histones; D008297:Male; D010743:Phospholipids / Q000502:physiology*; D011494:Protein Kinases / Q000378:metabolism*; D011817:Rabbits; D013379:Substrate Specificity; D013974:Thyroxine / Q000502:physiology*
D006454:Hemoglobins; D006657:Histones; D010743:Phospholipids; D011494:Protein Kinases; D013974:Thyroxine