TPA causes divergent responses of Ca2+-dependent and Ca2+-independent isoforms of PKC in the nuclei of Caco-2 cells

Frawley, B.; Tien, Xiao-Ying; Hartmann, S C; Wali, Ramesh K.; Niedziela, Sharon M.; Davidson, Nicholas O.; Sitrin, Michael D.; Brasitus, Thomas A.; Bissonnette, Marc

doi:10.1016/0167-4889(94)90182-1

Cited by 14 publications

(5 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Additionally, previous studies (1) from our laboratory showed that PMA-stimulated NHE-3 function and expression in Caco-2 cells occurred via downregulation of PKC␣. In this regard, both PKC and butyrate have been implicated in the regulation of other important cellular processes in colonic epithelial cells such as proliferation, differentiation, apoptosis, and tumorigenesis (2,6,13,17,21,31,45). Therefore, it is plausible to hypothesize that the effect of PMA on butyrate uptake occurs via a PKC-mediated pathway.…”

Section: Discussionmentioning

confidence: 96%

Regulation of butyrate uptake in Caco-2 cells by phorbol 12-myristate 13-acetate

Alrefai

Tyagi

Gill

et al. 2004

American Journal of Physiology-Gastrointestinal and Liver Physi

View full text Add to dashboard Cite

Butyrate and the other short-chain fatty acids (SCFAs) are the most abundant anions in the colonic lumen. Also, butyrate is the preferred energy source for colonocytes and has been shown to regulate colonic electrolyte and fluid absorption. Previous studies from our group have demonstrated that the HCO(3)(-)/SCFA(-) anion exchange process is one of the major mechanisms of butyrate transport across the purified human colonic apical membrane vesicles and the apical membrane of human colonic adenocarcinoma cell line Caco-2 and have suggested that it is mainly mediated via monocarboxylate transporter-1 (MCT-1) isoform. However, little is known regarding the regulation of SCFA transport by various hormones and signal transduction pathways. Therefore, the present studies were undertaken to examine whether hydrocortisone and phorbol 12-myristate 13-acetate (PMA) are involved in a possible regulation of the butyrate/anion exchange process in Caco-2 cells. The butyrate/anion exchange process was assessed by measuring a pH-driven [(14)C]butyrate uptake in Caco-2 cells. Our results demonstrated that 24-h incubation with PMA (1 microM) significantly increased [(14)C]butyrate uptake compared with incubation with 4alphaPMA (inactive form). In contrast, incubation with hydrocortisone had no significant effect on butyrate uptake in Caco-2 cells compared with vehicle (ethanol) alone. Induction of butyrate uptake by PMA appeared to be via an increase in the maximum velocity (V(max)) of the transport process with no significant changes in the K(m) of the transporter for butyrate. Parallel to the increase in the V(max) of [(14)C]butyrate uptake, the MCT-1 protein level was also increased in response to PMA incubation. Our studies demonstrated that the butyrate/anion exchange was increased in response to PMA treatment along with the induction in the level of MCT-1 expression in Caco-2 cells.

show abstract

Section: Discussionmentioning

confidence: 96%

Regulation of butyrate uptake in Caco-2 cells by phorbol 12-myristate 13-acetate

Alrefai

Tyagi

Gill

et al. 2004

American Journal of Physiology-Gastrointestinal and Liver Physi

View full text Add to dashboard Cite

show abstract

“…Little is known about the regulation and functions of the Ca 2ϩ -independent PKC isoforms. Frawley et al (10) demonstrated that PKC-was implicated in regulating gene expression induced by growth factors and hormones. Thus activation of PKC is not necessarily dependent on elevation of the [Ca 2ϩ ] i .…”

Section: Discussionmentioning

confidence: 99%

“…The high-speed supernatants (14,000 g, 3 min) were diluted 1:10 with buffer that did not contain detergent, and 20 l of the diluted extract were taken for analysis of enzyme activity, according to instructions supplied with the kit (GIBCO Life Technologies, Waverly, MA). Aliquots were incubated with lipid activator in the absence or presence of a specific PKC inhibitor for 20 min before the addition of buffer containing [ 32 P]ATP-20 M ATP and acetylated myelin basic protein (3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14). After an additional 5-min incubation at 23°C, 25 l were spotted onto phosphocellulose disks, washed, and placed in vials for liquid scintillation spectrophotometry.…”

Section: Saturation Analyses Of [ 3 H]125(oh) 2 D 3 Binding To Membrmentioning

confidence: 99%

A specific binding moiety for 1,25-dihydroxyvitamin D₃in basal lateral membranes of carp enterocytes

Nemere

Larsson

Sundell

2000

American Journal of Physiology-Endocrinology and Metabolism

View full text Add to dashboard Cite

Carp (Cyprinus carpio), a freshwater fish that lives in a low-calcium environment, and Atlantic cod (Gadus morhua), a seawater fish that lives in a high-calcium environment, were studied for the presence of a novel membrane binding protein ("receptor") for the vitamin D metabolite, 1,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)]. Basal lateral membranes from enterocytes of either species were prepared and analyzed for specific saturable binding. Membranes from carp revealed a dissociation constant of 1.23 nM with a maximal binding capacity of 212 fmol/mg protein. In comparison, membranes from Atlantic cod enterocytes revealed very low and nonsignificant levels of specific binding. The [(3)H]1,25(OH)(2)D(3) binding activity in carp was further characterized for protein dependence, detergent extractability, and competition for binding with the metabolites 25(OH)D(3) and 24R,25(OH)(2)D(3). Finally, introduction of 1,25(OH)(2)D(3) to isolated carp enterocytes enhanced protein kinase C activity within 5 min, whereas intracellular Ca(2+) concentrations were unaffected by a range of 1,25(OH)(2)D(3) concentrations, as judged by fura 2 fluorescence. Thus the binding moiety may be a putative plasma membrane receptor for vitamin D, because it is functionally coupled to at least one signal transduction pathway.

show abstract

“…Less is known regarding the regulation and functions of the Ca2+-independent PKC isoforms 6, E, and 4, but, like the better-characterized classical isoforms, their effects are cell specific. We have recently demonstrated that PKC-4, an atypical member of the PKC family of isozymes implicated in regulating gene expression induced by growth factors and hormones (39,40), is constitutively expressed in the nucleus of Caco-2 cells (41).…”

Section: Discussionmentioning

confidence: 99%

1,25-Dihydroxyvitamin D3 and 12-O-tetradecanoyl phorbol 13-acetate cause differential activation of Ca(2+)-dependent and Ca(2+)-independent isoforms of protein kinase C in rat colonocytes.

Bissonnette

Wali²,

Hartmann³

et al. 1995

J. Clin. Invest.

View full text Add to dashboard Cite

TPA causes divergent responses of Ca2+-dependent and Ca2+-independent isoforms of PKC in the nuclei of Caco-2 cells

Cited by 14 publications

References 21 publications

Regulation of butyrate uptake in Caco-2 cells by phorbol 12-myristate 13-acetate

Regulation of butyrate uptake in Caco-2 cells by phorbol 12-myristate 13-acetate

A specific binding moiety for 1,25-dihydroxyvitamin D₃in basal lateral membranes of carp enterocytes

1,25-Dihydroxyvitamin D3 and 12-O-tetradecanoyl phorbol 13-acetate cause differential activation of Ca(2+)-dependent and Ca(2+)-independent isoforms of protein kinase C in rat colonocytes.

Contact Info

Product

Resources

About

TPA causes divergent responses of Ca2+-dependent and Ca2+-independent isoforms of PKC in the nuclei of Caco-2 cells

Cited by 14 publications

References 21 publications

Regulation of butyrate uptake in Caco-2 cells by phorbol 12-myristate 13-acetate

Regulation of butyrate uptake in Caco-2 cells by phorbol 12-myristate 13-acetate

A specific binding moiety for 1,25-dihydroxyvitamin D3in basal lateral membranes of carp enterocytes

1,25-Dihydroxyvitamin D3 and 12-O-tetradecanoyl phorbol 13-acetate cause differential activation of Ca(2+)-dependent and Ca(2+)-independent isoforms of protein kinase C in rat colonocytes.

Contact Info

Product

Resources

About

A specific binding moiety for 1,25-dihydroxyvitamin D₃in basal lateral membranes of carp enterocytes