TY - JOUR
T1 - Regulation of transin/stromelysin and V130 gene expression by intracellular calcium
AU - Rodland, Karin D.
AU - Lenormand, Philippe
AU - Muldoon, Leslie L.
AU - Magun, Bruce E.
PY - 1992/6
Y1 - 1992/6
N2 - Changes in intracellular Ca++ levels are observed as a second messenger in response to a number of cellular agonists, including epidermal growth factor, transforming growth factor β1, and endothelin-1. The role of elevated intracellular Ca++ in transducing the effects of these three agonists on gene expression has been studied using two target genes: transin/stromelysin-1 and the endogenous murine retrovirus VL30. Although the effects of EGF and TGFβ1 on transin/ stromelysin-1 mRNA expression appear to be independent of these agonists' effects on intracellular Ca++ levels, elevated Ca++ interacted synergistically with activators of pkC to induce transin expression, even though neither agent alone could induce transin/stromelysin-1 expression. In contrast, the integrated VL30 retrovirus could be induced by Ca++ ionophores alone, and induction of VL30 mRNA by other agonists was blocked if intracellular Ca++ levels were held below a threshold value of 165 nM with Ca++ chelators. Genetic analysis of the VL30 upstream regulatory region indicated that a triple-repeat element present in the VL30 long-terminal repeat could function as an inducible enhancer, but responsiveness to either EGF or pkC activation required the concomitant elevation of intracellular Ca++. Because EGF was capable of inducing expression even in pkC-depleted cells, providing Ca++ levels were elevated, these results indicate that elevated intracellular Ca++ is capable of interacting synergistically with multiple signaling pathways to stimulate increased gene expression.
AB - Changes in intracellular Ca++ levels are observed as a second messenger in response to a number of cellular agonists, including epidermal growth factor, transforming growth factor β1, and endothelin-1. The role of elevated intracellular Ca++ in transducing the effects of these three agonists on gene expression has been studied using two target genes: transin/stromelysin-1 and the endogenous murine retrovirus VL30. Although the effects of EGF and TGFβ1 on transin/ stromelysin-1 mRNA expression appear to be independent of these agonists' effects on intracellular Ca++ levels, elevated Ca++ interacted synergistically with activators of pkC to induce transin expression, even though neither agent alone could induce transin/stromelysin-1 expression. In contrast, the integrated VL30 retrovirus could be induced by Ca++ ionophores alone, and induction of VL30 mRNA by other agonists was blocked if intracellular Ca++ levels were held below a threshold value of 165 nM with Ca++ chelators. Genetic analysis of the VL30 upstream regulatory region indicated that a triple-repeat element present in the VL30 long-terminal repeat could function as an inducible enhancer, but responsiveness to either EGF or pkC activation required the concomitant elevation of intracellular Ca++. Because EGF was capable of inducing expression even in pkC-depleted cells, providing Ca++ levels were elevated, these results indicate that elevated intracellular Ca++ is capable of interacting synergistically with multiple signaling pathways to stimulate increased gene expression.
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U2 - 10.1111/1523-1747.ep12462100
DO - 10.1111/1523-1747.ep12462100
M3 - Article
C2 - 1588122
AN - SCOPUS:0026550856
SN - 0022-202X
VL - 98
SP - S12-S16
JO - Journal of Investigative Dermatology
JF - Journal of Investigative Dermatology
IS - 6 SUPPL.
ER -