Ligand-induced tyrosine phosphorylation of cysteinyl leukotriene receptor 1 triggers internalization and signaling in intestinal epithelial cells

TY - JOUR

T1 - Ligand-induced tyrosine phosphorylation of cysteinyl leukotriene receptor 1 triggers internalization and signaling in intestinal epithelial cells

AU - Parhamifar, Ladan

AU - Sime, Wondossen

AU - Yudina, Yuliana

AU - Vilhardt, Frederik

AU - Mörgelin, Matthias

AU - Sjölander, Anita

PY - 2010/12/1

Y1 - 2010/12/1

N2 - Background: Leukotriene D4 (LTD4) belongs to the bioactive lipid group known as eicosanoids and has implications in pathological processes such as inflammation and cancer. Leukotriene D4 exerts its effects mainly through two different Gprotein- coupled receptors, CysLT1 and CysLT2. The high affinity LTD4 receptor CysLT1R exhibits tumor-promoting properties by triggering cell proliferation, survival, and migration in intestinal epithelial cells. In addition, increased expression and nuclear localization of CysLT1R correlates with a poorer prognosis for patients with colon cancer. Methodology/Principal Findings: Using a proximity ligation assay and immunoprecipitation, this study showed that endogenous CysLT1R formed heterodimers with its counter-receptor CysLT2R under basal conditions and that LTD4 triggers reduced dimerization of CysLTRs in intestinal epithelial cells. This effect was dependent upon a parallel LTD4-induced increase in CysLT1R tyrosine phosphorylation. Leukotriene D4 also led to elevated internalization of CysLT1Rs from the plasma membrane and a simultaneous increase at the nucleus. Using sucrose, a clathrin endocytic inhibitor, dominantnegative constructs, and siRNA against arrestin-3, we suggest that a clathrin-, arrestin-3, and Rab-5-dependent process mediated the internalization of CysLT1R. Altering the CysLT1R internalization process at either the clathrin or the arrestin-3 stage led to disruption of LTD4-induced Erk1/2 activation and up-regulation of COX-2 mRNA levels. Conclusions/Significance: Our data suggests that upon ligand activation, CysLT1R is tyrosine-phosphorylated and released from heterodimers with CysLT2R and, subsequently, internalizes from the plasma membrane to the nuclear membrane in a clathrin-, arrestin-3-, and Rab-5-dependent manner, thus, enabling Erk1/2 signaling and downstream transcription of the COX-2 gene.

AB - Background: Leukotriene D4 (LTD4) belongs to the bioactive lipid group known as eicosanoids and has implications in pathological processes such as inflammation and cancer. Leukotriene D4 exerts its effects mainly through two different Gprotein- coupled receptors, CysLT1 and CysLT2. The high affinity LTD4 receptor CysLT1R exhibits tumor-promoting properties by triggering cell proliferation, survival, and migration in intestinal epithelial cells. In addition, increased expression and nuclear localization of CysLT1R correlates with a poorer prognosis for patients with colon cancer. Methodology/Principal Findings: Using a proximity ligation assay and immunoprecipitation, this study showed that endogenous CysLT1R formed heterodimers with its counter-receptor CysLT2R under basal conditions and that LTD4 triggers reduced dimerization of CysLTRs in intestinal epithelial cells. This effect was dependent upon a parallel LTD4-induced increase in CysLT1R tyrosine phosphorylation. Leukotriene D4 also led to elevated internalization of CysLT1Rs from the plasma membrane and a simultaneous increase at the nucleus. Using sucrose, a clathrin endocytic inhibitor, dominantnegative constructs, and siRNA against arrestin-3, we suggest that a clathrin-, arrestin-3, and Rab-5-dependent process mediated the internalization of CysLT1R. Altering the CysLT1R internalization process at either the clathrin or the arrestin-3 stage led to disruption of LTD4-induced Erk1/2 activation and up-regulation of COX-2 mRNA levels. Conclusions/Significance: Our data suggests that upon ligand activation, CysLT1R is tyrosine-phosphorylated and released from heterodimers with CysLT2R and, subsequently, internalizes from the plasma membrane to the nuclear membrane in a clathrin-, arrestin-3-, and Rab-5-dependent manner, thus, enabling Erk1/2 signaling and downstream transcription of the COX-2 gene.

U2 - 10.1371/journal.pone.0014439

DO - 10.1371/journal.pone.0014439

M3 - Journal article

C2 - 21203429

SN - 1932-6203

VL - 5

SP - e14439

JO - PLoS ONE

JF - PLoS ONE

IS - 12

ER -