Dissection of roles of Densin-180, a cell polarity molecule, in synapses

点击翻译按钮获取中文摘要

To dissect the function of Densin-180, we overexpressed various mutants of Densin-180 in cultured cells and observed the intracellular localization of Densin-180. When a mutant lacking the leucine-rich repeats was overexpressed in Neuro2a cells, the mutant did not localize at the plasma membrane, but localized in the cytoplasm. When the C-terminal region of Densin-180, including the PDZ domain, was overexpressed in HeLa cells, the mutant localized on stress fiber. We also found that the residues cysteine 14 and cysteine 16 in the N-terminal region (1-32 amino acids) of ERBIN, a homologue of Densin-180, is important for the localization of ERBIN at the plasma membrane. We produced the anti-phospho-Densin-180 antibody which recognized the site phosphorylated by CaMKII. The antibody could detect the phosphorylation of overexpressed Densin-180 after ionomycin treatment. It was reported that in the mutant of C.elegans let-413, a homologue of Densin-180, AJM-1, a protein that showed homology to trichohyalin and plectin, was mislocalized. We identified trichoplein, a novel protein that showed homology to trichohyalin and plectin, as a keratin-binding protein.