کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1947549 | 1054616 | 2014 | 12 صفحه PDF | دانلود رایگان |
• We identified AP-2μ2 as a molecule associated with the cytoplasmic region of CL-P1.
• AP-2μ2 was essential for CL-P1 mediated endocytosis in CL-P1 transfectants.
• YXXΦ sequences associated with AP-2μ2 play an important role in OxLDL endocytosis.
• The endocytosis due to CL-P1 was mediated by clathrin, dynamin and adaptin proteins.
BackgroundScavenger receptor CL-P1 (collectin placenta 1) has been found recently as a first membrane-type collectin which is mainly expressed in vascular endothelial cells. CL-P1 can endocytose OxLDL as well as microbes but in general, the endocytosis mechanism of a scavenger receptor is not well elucidated.MethodsWe screened a placental cDNA library using a yeast two-hybrid system to detect molecules associated with the cytoplasmic domain of CL-P1. We analyzed the binding and endocytosis of several ligands in CL-P1 transfectants and performed the inhibition study using tyrphostin A23 which is a specific inhibitor of tyrosine kinase, especially in μ2-dependent endocytosis and the site-directed mutagenesis in the endocytosis YXXΦ motif in CL-P1 cytoplasmic region. Furthermore, the SiRNA study of clathrin, adaptor AP-2 and dynamin-2 during the endocytosis of OxLDL in CL-P1 transfectant cells was carried out.ResultsWe identified μ2 subunit of the AP-2 adaptor complex as a molecule associated with the cytoplasmic region of CL-P1. We demonstrated that AP-2μ2 was essential for CL-P1 mediated endocytosis of OxLDL in CL-P1 transfectant cells and its endocytosis was also mediated by clathrin, dynamin and adaptin complex molecules.ConclusionsTyrosine-based YXXΦ sequences play an important role in CL-P1-mediated OxLDL endocytosis associated with AP-2μ2.General SignificanceThis might be the first finding of the clear endocytosis mechanism in scavenger receptor CL-P1.
Journal: Biochimica et Biophysica Acta (BBA) - General Subjects - Volume 1840, Issue 11, November 2014, Pages 3226–3237