scholarly journals Analysis of insulin receptor phosphorylation sites in intact rat liver cells by two-dimensional phosphopeptide mapping. Predominance of the tris-phosphorylated form of the kinase domain after stimulation by insulin

1991 ◽  
Vol 275 (1) ◽  
pp. 15-21 ◽  
Author(s):  
T Issad ◽  
J M Tavaré ◽  
R M Denton
Keyword(s):  
Insulin Receptor ◽  
Rat Liver ◽  
Insulin Receptors ◽  
Kinase Domain ◽  
Two Dimensional ◽  
Tyrosine Residues ◽  
C Terminus ◽  
Rat Liver Cells ◽  
Wheat Germ Lectin ◽  
Dimensional Mapping

1. Insulin receptors were partially purified from rat liver by chromatography on wheat-germ-lectin-Sepharose. Incubation with [gamma-32P]ATP in the presence of insulin resulted in increased phosphorylation of the beta-subunit on both tyrosine and serine residues. Two-dimensional mapping of tryptic peptides showed that, in agreement with previous studies using preparations of receptors from other sources, the tyrosine residues involved were the three tyrosines in the kinase domain (corresponding to tyrosines 1158, 1162 and 1163 of the human receptor) plus two tyrosines close to the C-terminus (corresponding to tyrosines 1328 and 1334). 2. The effects of insulin on the phosphorylation of receptors within intact rat liver cells were determined by incubating cells in the presence of [32P]Pi for 50 min and then with or without insulin for a further 10 min. The labelled receptors were then rapidly isolated by sequential use of wheat-germ-lectin-Sepharose chromatography and immuno-isolation using a monoclonal antibody to the C-terminal end of the beta-subunit. 3. Insulin was found to increase overall phosphorylation of the receptor nearly 3-fold. Two-dimensional mapping was then carried out in combination with phosphoamino acid analysis. This revealed that the pattern of phosphorylation of the receptors in cells incubated in the absence and presence of insulin exhibited a number of marked differences from that observed in previous studies on intact cells, which had been restricted to cells expressing very high levels of insulin receptors such as certain hepatoma-derived cells or cells transfected with insulin receptor cDNA. The differences in the effects of insulin included a larger increase in the proportion of receptors being phosphorylated on the three tyrosine residues of the kinase domain, no apparent phosphorylation of the two tyrosine residues close to the C-terminus and no increase in either threonine or overall serine phosphorylation. 4. The receptors appeared to be phosphorylated on a number of different serine residues in cells incubated in the absence of insulin. Evidence for both increases and decreases in the phosphorylation of specific serine residues on addition of insulin was obtained. 5. It is concluded that care should be taken when extrapolating findings on the phosphorylation of the insulin receptor within cultured cells to more physiological situations.

scholarly journals Studies on the autophosphorylation of the insulin receptor from human placenta. Analysis of the sites phosphorylated by two-dimensional peptide mapping

1988 ◽  
Vol 252 (2) ◽  
pp. 607-615 ◽  
Author(s):  
J M Tavaré ◽  
R M Denton
Keyword(s):  
Thin Layer ◽  
Insulin Receptor ◽  
Peptide Mapping ◽  
Beta Subunit ◽  
Two Dimensional ◽  
Intact Cells ◽  
Tyrosine Residues ◽  
Domain 3 ◽  
Receptor Beta

1. A partially purified preparation of human placental insulin receptors was incubated with [gamma-32P]ATP in the presence or absence of insulin. The 32P-labelled insulin-receptor beta-subunits were then isolated, cleaved with trypsin followed by protease V8 and the [32P]phosphopeptides generated were analysed by thin layer electrophoresis and chromatography. This approach revealed that insulin stimulates autophosphorylation of the insulin-receptor beta-subunit in vitro on at least seven tyrosine residues distributed among three distinct domains. 2. One domain (domain 2), containing tyrosine residues 1146, 1150 and 1151 was the most rapidly phosphorylated and could be recovered as mono-, di- and triphosphorylated peptides cleaved by trypsin at Arg-1143 and either Lys-1153 or Lys-1156. Multiple phosphorylation of this domain appears to partially inhibit the cleavage at Lys-1153 by trypsin. 3. In a second domain (domain 3) containing two phosphorylated tyrosine residues at positions 1316 and 1322 the tyrosines were phosphorylated more slowly than those in domain 2. This domain is close to the C-terminus of the beta-subunit polypeptide chain. 4. At least two further tyrosine residues appeared to be phosphorylated after those in domains 2 and 3. These residues probably residue within a domain lying in close proximity to the inner face of the plasma membrane containing tyrosines 953, 960 and 972, but conclusive evidence is still required. 5. The two-dimensional thin-layer analysis employed in this study to investigate insulin-receptor phosphorylation has several advantages over previous methods based on reverse-phase chromatography. It allows greater resolution of 32P-labelled tryptic peptides and, when coupled to radioautography, is considerably more sensitive. The approach can be readily adapted to study phosphorylation of the insulin receptor within intact cells.

scholarly journals Impairment of the liver insulin receptor autoactivation cascade at full-term pregnancy in the rat

1995 ◽  
Vol 311 (2) ◽  
pp. 523-529 ◽  
Author(s):  
C Martinez ◽  
J C Molero ◽  
P Ruiz ◽  
A Del Arco ◽  
A Andres ◽  
...  
Keyword(s):  
Insulin Receptor ◽  
Structural Changes ◽  
Insulin Receptors ◽  
Kinase Domain ◽  
Full Term ◽  
Beta Subunits ◽  
Pregnant Rats ◽  
Functional Changes ◽  
Domain Truncation ◽  
Alternative Sites

Partially purified liver insulin receptors from full-term pregnant rats show decreased autophosphorylation rates if compared with receptors from virgins. We studied the molecular mechanism of this phenomenon, looking at possible structural and functional changes of several domains. The ATP-binding domain seems to be unaltered in receptors from pregnant rats since Km for ATP was similar to that observed in virgins. In contrast, the Vmax. is decreased some 45%, suggesting changes in the kinase domain. Truncation of a fragment of 10 kDa from the C-terminal tail does not normalize the kinase activity in receptors from pregnant rats, suggesting that this domain is not involved in the inhibitory regulation. Treatment with alkaline phosphatase increases the [32P]Pi incorporation into receptors from pregnant rats; however, the autophosphorylation remains lower than that observed in virgin rats. Tryptic phosphopeptide maps of phosphorylated receptors show that the same phosphopeptides are present in receptors from virgin and pregnant rats. However, the progression through the autoactivation cascade in the kinase domain is impaired in receptors from pregnant rats. Differences in the cleavage by trypsin at the two alternative sites in the kinase domain were observed, indicating possible structural changes in receptors from pregnant rats that could be related to the impairment of the autoactivation cascade. Integrity of the alpha- and beta-subunits, as well as differential expression of the two receptor isotypes, were shown to be unaltered. We conclude that (1) the decreased autophosphorylation rate of the liver insulin receptor from pregnant rats is associated with the impairment of its autoactivation cascade, probably as a consequence of the basal Ser/Thr phosphorylation; and (2) the inhibition of the autoactivation cascade does not account for the overall inhibition of autophosphorylation observed in receptors from pregnant rats.

Expression of insulin-like growth factor II (IGF-II) and IGF-II, IGF-I and insulin receptors mRNAs in isolated non-parenchymal rat liver cells

1992 ◽  
Vol 14 (1) ◽  
pp. 30-34 ◽  
Author(s):  
Frédérique Zindy ◽  
Eugenia Lamas ◽  
Sylvie Schmidt ◽  
André Kirn ◽  
Christian Brechot
Keyword(s):  
Growth Factor ◽  
Rat Liver ◽  
Insulin Receptors ◽  
Liver Cells ◽  
Insulin Like Growth Factor ◽  
Factor Ii ◽  
Igf I ◽  
Rat Liver Cells

scholarly journals Tyrosine phosphorylation of two cytosolic proteins of 50 kDa and 35 kDa in rat liver by insulin-receptor kinase in vitro

1987 ◽  
Vol 248 (1) ◽  
pp. 27-33 ◽  
Author(s):  
Y C Kwok ◽  
C C Yip
Keyword(s):  
Insulin Receptor ◽  
Rat Liver ◽  
Growth Factor Receptor ◽  
Insulin Receptors ◽  
Artificial Substrates ◽  
Receptor Kinase ◽  
Insulin Receptor Tyrosine Kinase ◽  
Cytosolic Proteins ◽  
Insulin Receptor Kinase

Insulin-receptor tyrosine kinase can phosphorylate a variety of artificial substrates in vitro. Its physiological substrate(s), however, remains unknown. In the present study, we show that immobilized insulin receptors phosphorylate tyrosine residues of two cytosolic proteins of 50 kDa and 35 kDa in rat liver. Phosphorylation of these two proteins required Mn2+- or Mg2+-ATP as the phosphate donor. Phosphorylation was time- and temperature-dependent. Furthermore, the rate of phosphorylation of the two proteins was related to the autophosphorylated state of the insulin receptor. The pI of the phosphorylated 50 kDa and 35 kDa proteins was 5.4 and 5.6 respectively. These proteins were present in low abundance. They were not related to each other, nor to the insulin receptor, as demonstrated by in-gel proteolytic digestion and by immunoprecipitation using antibodies produced against them. They were specific substrates for the insulin receptor kinase, since they were not phosphorylated by epidermal-growth-factor-receptor kinase. These observations suggest that the 50 kDa and 35 kDa cytosolic proteins may be endogenous substrates for the insulin-receptor kinase.

scholarly journals Hydrogen peroxide stimulates tyrosine phosphorylation of the insulin receptor and its tyrosine kinase activity in intact cells

1988 ◽  
Vol 250 (1) ◽  
pp. 95-101 ◽  
Author(s):  
O Koshio ◽  
Y Akanuma ◽  
M Kasuga
Keyword(s):  
Insulin Receptor ◽  
Kinase Activity ◽  
Intact Cell ◽  
Insulin Receptors ◽  
Beta Subunit ◽  
Receptor Kinase ◽  
Intact Cells ◽  
Tyrosine Residues ◽  
Insulin Receptor Kinase ◽  
Insulin Receptor Kinase Activity

H-35 rat hepatoma cells were labelled with [32P]orthophosphate and their insulin receptors isolated on wheat germ agglutinin (WGA)-agarose and anti-(insulin receptor) serum. The incubation of these cells with 10 mM-H2O2 for 10 min increased the phosphorylation of both the serine and tyrosine residues of the beta subunit of the insulin receptor. Next, insulin receptors were purified on WGA-agarose from control and H2O2-treated H-35 cells and the purified fractions incubated with [gamma-32P]ATP and Mn2+. Phosphorylation of the beta subunit of insulin receptors obtained from H2O2-treated cells was 150% of that of control cells. The kinase activity of the WGA-purified receptor preparation obtained from H2O2-treated cells, as measured by phosphorylation of src-related synthetic peptide, was increased about 4-fold over control cells. These data suggest that in intact cell systems, H2O2 may increase the insulin receptor kinase activity by inducing phosphorylation of the beta subunit of insulin receptor.

Antiserum to liver insulin receptor hyperpolarizes rat muscle

1983 ◽  
Vol 244 (1) ◽  
pp. C58-C60 ◽  
Author(s):  
K. Zierler ◽  
E. M. Rogus
Keyword(s):  
Skeletal Muscle ◽  
Insulin Receptor ◽  
Rat Liver ◽  
Rabbit Antiserum ◽  
Insulin Receptors ◽  
Metabolic Effects ◽  
Metabolic Responses ◽  
Maximum Effect ◽  
Half Maximum ◽  
Rat Muscle

Antibodies to insulin receptors have been reported to have some insulinlike metabolic effects. If insulin-induced electrical hyperpolarization of skeletal muscle is part of the transduction chain between receptor and certain metabolic responses, then receptor antiserum should hyperpolarize. The Jacobs antiserum (rabbit antiserum against rat liver insulin receptor) hyperpolarized rat caudofemoralis muscle. Maximum effect, about 4.5 mV, occurred at 1:10,000 dilution, half maximum at about 1:40,000. Maximum effect of antiserum was only as great as half maximum hyperpolarization by insulin on this muscle. 2-Deoxyglucose uptake was also stimulated by antiserum but required greater concentration than for hyperpolarization, and the stimulation was only by about one-third the maximum effect of insulin.

scholarly journals Subcutaneously Delivered Nano-Insulin Drug as Label Free Nanotheranostic

2021 ◽  
Author(s):  
Rıdvan Say ◽  
Almila Şenat ◽  
Özlem Biçen Ünlüer ◽  
Fahrettin Akyüz ◽  
Arzu Ersöz
Keyword(s):  
Liquid Chromatography ◽  
Insulin Receptor ◽  
Rat Liver ◽  
Insulin Receptors ◽  
Insulin Analog ◽  
Second Step ◽  
Label Free ◽  
Column Material ◽  
Reflectometric Interference Spectroscopy ◽  
The Relationship

Abstract In this study, it has aimed to understand the relationship between purified insulin and insulin receptor, also nanoinsulin and insulin receptors. The insulin receptor has separated from rat liver using a cryogel column material that is photosensitively insulin cross-linked in the Fast Protein Liquid Chromatography (FPLC) system based on the affinity between insulin and insulin receptor. In the second step, an isolated insulin receptor has used to synthesize insulin receptor cross-linked cryogels for purifying insulin from rats. Subcutaneously delivered nano-insulin drug has prepared from the purified insulin using AmiNoAcid (monomer) Decorated and Light Underpinning Conjugation Approach (ANADOLUCA) method. Lastly, Reflectometric Interference Spectroscopy (RIfS) study has performed to understand the interaction between purified insulin receptor and purified insulin, commercial insulin analog, and nano insulin. These studies have demonstrated that nano-insulin drugs can be effectively used as a theranostic platform to monitor affinity and blocking interactions of nanoprotein drug and its receptor.

scholarly journals Changes in insulin-receptor tyrosine, serine and threonine phosphorylation as a result of substitution of tyrosine-1162 with phenylalanine

1991 ◽  
Vol 274 (1) ◽  
pp. 173-179 ◽  
Author(s):  
J M Tavaré ◽  
M Dickens
Keyword(s):  
Insulin Receptor ◽  
Chinese Hamster Ovary Cells ◽  
Chinese Hamster ◽  
Insulin Receptors ◽  
Insulin Binding ◽  
Serine Phosphorylation ◽  
Beta Subunit ◽  
Intact Cells ◽  
Ovary Cells ◽  
Tyrosine Residues

Previous studies, by ourselves and others, have shown that tyrosine residues 1158, 1162 and 1163 are very rapidly autophosphorylated on the human insulin receptor after insulin binding and that this is followed by the autophosphorylation of tyrosine residues 1328 and 1334. The autophosphorylation of these tyrosine residues, and their role in transmembrane signalling, were examined by using Chinese-hamster ovary cells transfected with either normal intact insulin receptors or receptors in which tyrosine residues 1162 or 1162/1163 were substituted with phenylalanine. These studies show the following. (1) Tyrosine-1158 could still be autophosphorylated when tyrosine-1162 and -1163 were substituted with phenylalanine. (2) Insulin-stimulated insulin-receptor tyrosine phosphorylation in intact cells was complete within 30 s and was accompanied, after a lag of 2-5 min, by a rise in serine and threonine phosphorylation the beta-subunit. (3) Replacement of tyrosine-1162 with phenylalanine blocked insulin-stimulated threonine phosphorylation of the insulin receptor in intact cells. (4) Insulin-stimulated serine phosphorylation of the beta-subunit was found in both intact cells and partially purified receptor preparations incubated with [gamma-32P]ATP and was still apparent after the replacement of tyrosine-1162 with phenylalanine. (5) Our data strongly suggest that insulin-stimulated insulin-receptor serine and threonine phosphorylations are initiated through two distinct pathways, with only the latter showing a strict dependence on autophosphorylation of tyrosine-1162.

scholarly journals Inhibitory effect of fluoride on insulin receptor autophosphorylation and tyrosine kinase activity

1993 ◽  
Vol 291 (2) ◽  
pp. 615-622 ◽  
Author(s):  
F Viñals ◽  
X Testar ◽  
M Palacín ◽  
A Zorzano
Keyword(s):  
Tyrosine Kinase ◽  
Insulin Receptor ◽  
Binding Site ◽  
Human Placenta ◽  
Kinase Activity ◽  
Insulin Receptors ◽  
Inhibitory Effect ◽  
Beta Subunit ◽  
Tyrosine Kinase Activity ◽  
Tyrosine Residues

Fluoride is a nucleophilic reagent which has been reported to inhibit a variety of different enzymes such as esterases, asymmetrical hydrolases and phosphatases. In this report, we demonstrate that fluoride inhibits tyrosine kinase activity of insulin receptors partially purified from rat skeletal muscle and human placenta. Fluoride inhibited in a similar dose-dependent manner both beta-subunit autophosphorylation and tyrosine kinase activity for exogenous substrates. This inhibitory effect of fluoride was not due to the formation of complexes with aluminum and took place in the absence of modifications of insulin-binding properties of the insulin receptor. Fluoride did not complete with the binding site for ATP or Mn2+. Fluoride also inhibited the autophosphorylation and tyrosine kinase activity of receptors for insulin-like growth factor I from human placenta. Addition of fluoride to the pre-phosphorylated insulin receptor produced a slow (time range of minutes) inhibition of receptor kinase activity. Furthermore, fluoride inhibited tyrosine kinase activity in the absence of changes in the phosphorylation of prephosphorylated insulin receptors, and the sensitivity to fluoride was similar to the sensitivity of the unphosphorylated insulin receptor. The effect of fluoride-on tyrosine kinase activity was markedly decreased when insulin receptors were preincubated with the copolymer of glutamate/tyrosine. Prior exposure of receptors to free tyrosine or phosphotyrosine also prevented the inhibitory effect of fluoride. However, the protective effect of tyrosine or phosphotyrosine was maximal at low concentrations, suggesting the interaction of these compounds with the receptor itself rather than with fluoride. These data suggest: (i) that fluoride interacts directly and slowly with the insulin receptor, which causes inhibition of its phosphotransferase activity; (ii) that the binding site of fluoride is not structurally modified by receptor phosphorylation; and (iii) based on the fact that fluoride inhibits phosphotransferase activity in the absence of alterations in the binding of ATP, Mn2+ or insulin, we speculate that fluoride binding might affect the transfer of phosphate from ATP to the tyrosine residues of the beta-subunit of the insulin receptor and to the tyrosine residues of exogenous substrates.

Identification of a cis-Acting Element and a Novel trans-Acting Factor of the Human Insulin Receptor Gene in HepG2 and Rat Liver Cells

2001 ◽  
Vol 280 (2) ◽  
pp. 428-434 ◽  
Author(s):  
Kazuaki Yoshizato ◽  
Tetsuya Shirotani ◽  
Noboru Furukawa ◽  
Tetsuya Taguchi ◽  
Hiroyuki Motoshima ◽  
...  
Keyword(s):  
Insulin Receptor ◽  
Human Insulin ◽  
Rat Liver ◽  
Receptor Gene ◽  
Liver Cells ◽  
Insulin Receptor Gene ◽  
Cis Acting ◽  
Human Insulin Receptor ◽  
Rat Liver Cells
Sign in / Sign up

Export Citation Format

Share Document