RRC ID 44106
著者 Terasawa M, Uruno T, Mori S, Kukimoto-Niino M, Nishikimi A, Sanematsu F, Tanaka Y, Yokoyama S, Fukui Y.
タイトル Dimerization of DOCK2 is essential for DOCK2-mediated Rac activation and lymphocyte migration.
ジャーナル PLoS One
Abstract The migratory properties of lymphocytes depend on DOCK2, an atypical Rac activator predominantly expressed in hematopoietic cells. Although DOCK2 does not contain the Dbl homology domain typically found in guanine nucleotide exchange factors (GEFs), DOCK2 mediates the GTP-GDP exchange reaction for Rac via its DOCK homology region (DHR)-2 (also known as CZH2 or Docker) domain. DOCK2 DHR-2 domain is composed of three lobes, and Rac binding site and catalytic center are generated entirely from lobes B and C. On the other hand, lobe A has been implicated in dimer formation, yet its physiological significance remains unknown. Here, we report that lobe A-mediated DOCK2 dimerization is crucial for Rac activation and lymphocyte migration. We found that unlike wild-type DOCK2, DOCK2 mutant lacking lobe A failed to restore motility and polarity when expressed in thymoma cells and primary T cells lacking endogenous expression of DOCK2. Similar results were obtained with the DOCK2 point mutant having a defect in dimerization. Deletion of lobe A from the DHR-2 domain did not affect Rac GEF activity in vitro. However, fluorescence resonance energy transfer analyses revealed that lobe A is required for DOCK2 to activate Rac effectively during cell migration. Our results thus indicate that DOCK2 dimerization is functionally important under the physiological condition where only limited amounts of DOCK2 and Rac are localized to the plasma membrane.
巻・号 7(9)
ページ e46277
公開日 2012-1-1
DOI 10.1371/journal.pone.0046277
PII PONE-D-12-16780
PMID 23050005
PMC PMC3458822
MeSH Animals Cell Line Cell Movement / genetics Cell Movement / physiology* GTPase-Activating Proteins / genetics GTPase-Activating Proteins / metabolism* Guanine Nucleotide Exchange Factors / genetics Guanine Nucleotide Exchange Factors / metabolism Humans Immunoprecipitation Lymphocytes / cytology* Lymphocytes / metabolism* Mice Mice, Knockout Mice, Transgenic Microscopy, Fluorescence Protein Multimerization / genetics Protein Multimerization / physiology rac GTP-Binding Proteins / genetics rac GTP-Binding Proteins / metabolism*
IF 2.74
引用数 13
WOS 分野 CELL BIOLOGY
リソース情報
ヒト・動物細胞 293T(RCB2202)