Effect of protein kinase C on the plasma membrane calcium pump in purified beta cells

M. Hoenig, Keith L Knutson

Research output: Contribution to journalArticle

Abstract

The effect of protein kinase C activation on (Ca2+-Mg2+)-ATPase and 45Ca2+ uptake in purified plasma membranes and membrane vesicles from beta cells was examined. PKC activation was achieved by incubating cells for 10 or 30 min in 100 nM or 1 μM of the phorbol ester 12-O-tetradecanoylphorbol 13-acetate (TPA) and evident by translocation of the α-isoform from the cytosolic to the membrane fraction. (Ca2+-Mg2+)-ATPase had a K(m) for Ca2+ of 0.56 ± 0.17 μM and the V(max) was 120 ± 12 nmol/min*mg protein in membranes from cells treated with TPA, while it was 0.66 ± 0.14 μM and 135 ± 19 nmol/min*mg protein, respectively, in its absence. In inside-out vesicles 45Ca2+ uptake had a K(m) for Ca2+ of 79 ± 19 nM and a V(max) of 1.68 ± 0.43 nmol/min*mg protein in the presence of TPA. In the absence of TPA, the K(m) was 71 ± 17 nM, and the V(max) was 1.59 ± 0.39 nmol/min*mg protein, respectively. It is concluded that in beta cells PKC activation does not regulate (Ca2+-Mg2+)-ATPase activity or Ca2+ transport directly.

Original languageEnglish (US)
Pages (from-to)75-79
Number of pages5
JournalBiochemical Medicine and Metabolic Biology
Volume53
Issue number1
DOIs
StatePublished - 1994
Externally publishedYes

Fingerprint

Tetradecanoylphorbol Acetate
Cell membranes
Ca(2+) Mg(2+)-ATPase
Protein Kinase C
Acetates
Cell Membrane
Pumps
Calcium
Chemical activation
Membranes
Proteins
Protein Kinase C beta
Phorbol Esters
Protein Isoforms
Membrane Proteins

ASJC Scopus subject areas

  • Biochemistry
  • Endocrinology, Diabetes and Metabolism

Cite this

Effect of protein kinase C on the plasma membrane calcium pump in purified beta cells. / Hoenig, M.; Knutson, Keith L.

In: Biochemical Medicine and Metabolic Biology, Vol. 53, No. 1, 1994, p. 75-79.

Research output: Contribution to journalArticle

@article{8e3ef30208cb44d19d6e7f3c129d9698,
title = "Effect of protein kinase C on the plasma membrane calcium pump in purified beta cells",
abstract = "The effect of protein kinase C activation on (Ca2+-Mg2+)-ATPase and 45Ca2+ uptake in purified plasma membranes and membrane vesicles from beta cells was examined. PKC activation was achieved by incubating cells for 10 or 30 min in 100 nM or 1 μM of the phorbol ester 12-O-tetradecanoylphorbol 13-acetate (TPA) and evident by translocation of the α-isoform from the cytosolic to the membrane fraction. (Ca2+-Mg2+)-ATPase had a K(m) for Ca2+ of 0.56 ± 0.17 μM and the V(max) was 120 ± 12 nmol/min*mg protein in membranes from cells treated with TPA, while it was 0.66 ± 0.14 μM and 135 ± 19 nmol/min*mg protein, respectively, in its absence. In inside-out vesicles 45Ca2+ uptake had a K(m) for Ca2+ of 79 ± 19 nM and a V(max) of 1.68 ± 0.43 nmol/min*mg protein in the presence of TPA. In the absence of TPA, the K(m) was 71 ± 17 nM, and the V(max) was 1.59 ± 0.39 nmol/min*mg protein, respectively. It is concluded that in beta cells PKC activation does not regulate (Ca2+-Mg2+)-ATPase activity or Ca2+ transport directly.",
author = "M. Hoenig and Knutson, {Keith L}",
year = "1994",
doi = "10.1006/bmmb.1994.1060",
language = "English (US)",
volume = "53",
pages = "75--79",
journal = "Molecular Genetics and Metabolism",
issn = "1096-7192",
publisher = "Academic Press Inc.",
number = "1",

}

TY - JOUR

T1 - Effect of protein kinase C on the plasma membrane calcium pump in purified beta cells

AU - Hoenig, M.

AU - Knutson, Keith L

PY - 1994

Y1 - 1994

N2 - The effect of protein kinase C activation on (Ca2+-Mg2+)-ATPase and 45Ca2+ uptake in purified plasma membranes and membrane vesicles from beta cells was examined. PKC activation was achieved by incubating cells for 10 or 30 min in 100 nM or 1 μM of the phorbol ester 12-O-tetradecanoylphorbol 13-acetate (TPA) and evident by translocation of the α-isoform from the cytosolic to the membrane fraction. (Ca2+-Mg2+)-ATPase had a K(m) for Ca2+ of 0.56 ± 0.17 μM and the V(max) was 120 ± 12 nmol/min*mg protein in membranes from cells treated with TPA, while it was 0.66 ± 0.14 μM and 135 ± 19 nmol/min*mg protein, respectively, in its absence. In inside-out vesicles 45Ca2+ uptake had a K(m) for Ca2+ of 79 ± 19 nM and a V(max) of 1.68 ± 0.43 nmol/min*mg protein in the presence of TPA. In the absence of TPA, the K(m) was 71 ± 17 nM, and the V(max) was 1.59 ± 0.39 nmol/min*mg protein, respectively. It is concluded that in beta cells PKC activation does not regulate (Ca2+-Mg2+)-ATPase activity or Ca2+ transport directly.

AB - The effect of protein kinase C activation on (Ca2+-Mg2+)-ATPase and 45Ca2+ uptake in purified plasma membranes and membrane vesicles from beta cells was examined. PKC activation was achieved by incubating cells for 10 or 30 min in 100 nM or 1 μM of the phorbol ester 12-O-tetradecanoylphorbol 13-acetate (TPA) and evident by translocation of the α-isoform from the cytosolic to the membrane fraction. (Ca2+-Mg2+)-ATPase had a K(m) for Ca2+ of 0.56 ± 0.17 μM and the V(max) was 120 ± 12 nmol/min*mg protein in membranes from cells treated with TPA, while it was 0.66 ± 0.14 μM and 135 ± 19 nmol/min*mg protein, respectively, in its absence. In inside-out vesicles 45Ca2+ uptake had a K(m) for Ca2+ of 79 ± 19 nM and a V(max) of 1.68 ± 0.43 nmol/min*mg protein in the presence of TPA. In the absence of TPA, the K(m) was 71 ± 17 nM, and the V(max) was 1.59 ± 0.39 nmol/min*mg protein, respectively. It is concluded that in beta cells PKC activation does not regulate (Ca2+-Mg2+)-ATPase activity or Ca2+ transport directly.

UR - http://www.scopus.com/inward/record.url?scp=0027988603&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0027988603&partnerID=8YFLogxK

U2 - 10.1006/bmmb.1994.1060

DO - 10.1006/bmmb.1994.1060

M3 - Article

C2 - 7857684

AN - SCOPUS:0027988603

VL - 53

SP - 75

EP - 79

JO - Molecular Genetics and Metabolism

JF - Molecular Genetics and Metabolism

SN - 1096-7192

IS - 1

ER -