Starvation-increased insulin-dependent tyrosine phosphorylation of the 195-kDa protein in intact rat liver.
Insulin stimulates tyrosine phosphorylation of 175-195 kDa proteins including insulin receptor substrate-1 (IRS-1) in various tissues and cell types. In intact rat livers, starvation increased the insulin-dependent tyrosine phosphorylation of the insulin receptor and IRS-1 as has been described by others. Surprisingly, starvation greatly increased the tyrosine phosphorylation of the 195-kDa protein induced by insulin, indicating that this protein may be a new substrate of the insulin receptor kinase. The marked increase in tyrosine phosphorylation of the 195-kDa protein may have a physiological role in signal transmission in response to insulin under starvation conditions.
Ito
Y
Y
Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, University of Tokyo, Japan.
Takahashi
S
S
Takenaka
A
A
Hidaka
T
T
Noguchi
T
T
D000818:Animals; D007328:Insulin / Q000494:pharmacology*; D055504:Insulin Receptor Substrate Proteins; D008099:Liver / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D008970:Molecular Weight; D010750:Phosphoproteins / Q000378:metabolism; D010766:Phosphorylation; D011233:Precipitin Tests; D011506:Proteins / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D011972:Receptor, Insulin / Q000187:drug effects* / Q000378:metabolism; D013217:Starvation / Q000378:metabolism*; D014443:Tyrosine / Q000737:chemistry / Q000378:metabolism*
D007328:Insulin; D055504:Insulin Receptor Substrate Proteins; C526296:Irs1 protein, rat; D010750:Phosphoproteins; D011506:Proteins; D014443:Tyrosine; D011972:Receptor, Insulin