A novel mechanism for the insulin-like effect of vanadate on glycogen synthase in rat adipocytes.

Tamura, Shinji; Brown, Thomas A.; Whipple, Judith H.; Fujita‐Yamaguchi, Yoko; Dubler, Robert E.; Cheng, Kang; Larner, Joseph

doi:10.1016/s0021-9258(20)82192-9

Cited by 326 publications

(14 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Our results show that vanadate, in addition to the previously reported insulin mimetic effects (1)(2)(3)(4)(5)(6)(7)(8)(9), can also reproduce the hormone action on the expression of L-type pyruvate kinase gene. Like insulin, in the absence of glucose, vanadate is inefficient in stimulating the expression of the L-type pyruvate kinase gene.…”

Section: Discussionsupporting

confidence: 68%

See 1 more Smart Citation

Vanadate Induction of L-type Pyruvate Kinase mRNA in Adult Rat Hepatocytes in Primary Culture

et al. 1991

View full text Add to dashboard Cite

In primary culture of adult rat hepatocytes, vanadate in the presence of glucose stimulates the expression of the liver (L-type) pyruvate kinase gene. Glucose by itself was inactive, and vanadate, like insulin, was also inefficient in the absence of glucose. Similar results were obtained on glucokinase gene expression. An analogue of cAMP, 8-(4-chlorophenylthio)-cAMP, inhibited the production of L-type pyruvate kinase and glucokinase mRNAs in the presence of glucose plus vanadate.

show abstract

Section: Discussionsupporting

confidence: 68%

“…V anadate has been reported to be a potent insulin mimetic agent in many cells (1)(2)(3)(4)(5)(6)(7). Oral administration of this compound to diabetic animals normalizes blood glucose concentration (8) and restores liver glycogen and fructose-2,6-bisphosphate levels and glucokinase and 6-phosphofructo-2-kinase activities (9).…”

mentioning

confidence: 99%

Vanadate Induction of L-type Pyruvate Kinase mRNA in Adult Rat Hepatocytes in Primary Culture

et al. 1991

View full text Add to dashboard Cite

show abstract

“…o-Vanadate has been reported to have other cellular effects, including activation of the insulin receptor kinase (66), a G-protein coupled to PLC (53), and Ca2+ influx (48), which could partially mimic the effects of angiotensin II. The potentially pleiotropic effects of o-vanadate may contribute to the marked synergism between A23187 and o-vanadate (Fig.…”

Section: Discussionmentioning

confidence: 99%

Angiotensin II Stimulates Protein-Tyrosine Phosphorylation in a Calcium-Dependent Manner

Huckle

Prokop

et al. 1990

Molecular and Cellular Biology

View full text Add to dashboard Cite

Cellular responses to epidermal growth factor (EGF) are dependent on the tyrosine-specific protein kinase activity of the cell-surface EGF receptor. Previous studies using WB rat liver epithelial cells have detected at least 10 proteins whose phosphotyrosine (P-Tyr) content is increased by EGF. In this study, we have examined alternate modes of activating tyrosine phosphorylation. Treatment of WB cells with hormones linked to Ca2+ mobilization and protein kinase C (PKC) activation, including angiotensin II, [Arg8]vasopressin, or epinephrine, stimulated rapid (less than or equal to 15-s) and transient increases in the P-Tyr content of several proteins (p120/125, p75/78, and p66). These proteins, detected by anti-P-Tyr immunoblotting, were similar in molecular weight to a subset of EGF-sensitive P-Tyr-containing proteins (P-Tyr-proteins). The increased P-Tyr content was confirmed by [32P]phosphoamino acid analysis of proteins recovered by anti-P-Tyr immunoprecipitation. Elevating intracellular [Ca2+] with the ionophore A23187 or ionomycin or with the tumor promoter thapsigargin mimicked the effects of hormones on tyrosine phosphorylation, whereas treatment with a PKC-activating phorbol ester did not. In addition, responses to angiotensin II were not diminished in PKC-depleted cells. Ca2+ mobilization, measured by fura-2 fluorescence, was coincident with the increase in tyrosine phosphorylation in response to angiotensin II or thapsigargin. Loading cells with the intracellular Ca2+ chelator bis-(o-aminophenoxy)ethane-N ,N ,N' , N'-tetraacetic acid (BAPTA) inhibited the appearance of all P-Tyr-proteins in response to angiotensin II, thapsigargin, or ionophores, as well as two EGF-stimulated P-Tyr-proteins. The majority of EGF-stimulated P-Tyr-proteins were not affected by BAPTA. These studies indicate that angiotensin II can alter protein-tyrosine phosphorylation in a manner that is secondary to, and apparently dependent on, Ca2+ mobilization. Thus, ligands such as EGF and angiotensin II, which act through distinct types of receptors, may activate secondary pathways involving tyrosine phosphorylation. These results also raise the possibility that certain growth-promoting effects of Ca2+ -mobilizing agents such as angiotensin II may be mediated via tyrosine phosphorylation.

show abstract

“…4b), both of which contain an ISRE in their promoter region. Although vanadate is generally known to inhibit protein tyrosine phosphatases (9), it may also directly stimulate protein tyrosine kinases such that some insulin-regulated signaling events can be mimicked by this agent (13,14,25). It therefore remains unclear whether vanadate activates FcRF-y and induces ISG54 and GBP mRNA by decreasing FIG.…”

Section: Resultsmentioning

confidence: 99%

In Vitro Activation of a Transcription Factor by Gamma Interferon Requires a Membrane-Associated Tyrosine Kinase and Is Mimicked by Vanadate

Igarashi

David

Larner

et al. 1993

Molecular and Cellular Biology

View full text Add to dashboard Cite

Gamma interferon (IFN-gamma) activates the formation of a DNA-binding protein complex (FcRF gamma) that recognizes the gamma response region (GRR) of the promoter for the human high-affinity Fc gamma receptor. In a membrane-enriched fraction prepared from human peripheral blood monocytes, IFN-gamma activation of FcRF gamma occurred within 1 min and was ATP dependent. Activation of FcRF gamma required a tyrosine kinase activity, and recognition of the GRR sequence by FcRF gamma could be abrogated by treatment with a tyrosine-specific protein phosphatase. Treatment of cells with vanadate alone resulted in the formation of FcRF gamma without the need for IFN-gamma. UV cross-linking and antibody competition experiments demonstrated that the FcRF gamma complex was composed of at least two components: the 91-kDa protein of the IFN-alpha-induced transcription complex ISGF3 and a 43-kDa component that bound directly to the GRR. Therefore, specificity for IFN-induced transcriptional activation of early response genes requires at least two events: (i) ligand-induced activation of membrane-associated protein by tyrosine phosphorylation and (ii) formation of a complex composed of an activated membrane protein(s) and a sequence-specific DNA-binding component.

show abstract

A novel mechanism for the insulin-like effect of vanadate on glycogen synthase in rat adipocytes.

Cited by 326 publications

References 40 publications

Vanadate Induction of L-type Pyruvate Kinase mRNA in Adult Rat Hepatocytes in Primary Culture

Vanadate Induction of L-type Pyruvate Kinase mRNA in Adult Rat Hepatocytes in Primary Culture

Angiotensin II Stimulates Protein-Tyrosine Phosphorylation in a Calcium-Dependent Manner

In Vitro Activation of a Transcription Factor by Gamma Interferon Requires a Membrane-Associated Tyrosine Kinase and Is Mimicked by Vanadate

Contact Info

Product

Resources

About