| Structural highlights
Function
[DOCK8_MOUSE] Potential guanine nucleotide exchange factor (GEF). GEF proteins activate some small GTPases by exchanging bound GDP for free GTP (By similarity). [CDC42_HUMAN] Plasma membrane-associated small GTPase which cycles between an active GTP-bound and an inactive GDP-bound state. In active state binds to a variety of effector proteins to regulate cellular responses. Involved in epithelial cell polarization processes. Regulates the bipolar attachment of spindle microtubules to kinetochores before chromosome congression in metaphase. Plays a role in the extension and maintenance of the formation of thin, actin-rich surface projections called filopodia. Mediates CDC42-dependent cell migration.[1] [2] [3]
Publication Abstract from PubMed
To migrate efficiently through the interstitium, dendritic cells (DCs) constantly adapt their shape to the given structure of the extracellular matrix and follow the path of least resistance. It is known that this amoeboid migration of DCs requires Cdc42, yet the upstream regulators critical for localization and activation of Cdc42 remain to be determined. Mutations of DOCK8, a member of the atypical guanine nucleotide exchange factor family, causes combined immunodeficiency in humans. In the present study, we show that DOCK8 is a Cdc42-specific guanine nucleotide exchange factor that is critical for interstitial DC migration. By generating the knockout mice, we found that in the absence of DOCK8, DCs failed to accumulate in the lymph node parenchyma for T-cell priming. Although DOCK8-deficient DCs migrated normally on 2-dimensional surfaces, DOCK8 was required for DCs to crawl within 3-dimensional fibrillar networks and to transmigrate through the subcapsular sinus floor. This function of DOCK8 depended on the DHR-2 domain mediating Cdc42 activation. DOCK8 deficiency did not affect global Cdc42 activity. However, Cdc42 activation at the leading edge membrane was impaired in DOCK8-deficient DCs, resulting in a severe defect in amoeboid polarization and migration. Therefore, DOCK8 regulates interstitial DC migration by controlling Cdc42 activity spatially.
DOCK8 is a Cdc42 activator critical for interstitial dendritic cell migration during immune responses.,Harada Y, Tanaka Y, Terasawa M, Pieczyk M, Habiro K, Katakai T, Hanawa-Suetsugu K, Kukimoto-Niino M, Nishizaki T, Shirouzu M, Duan X, Uruno T, Nishikimi A, Sanematsu F, Yokoyama S, Stein JV, Kinashi T, Fukui Y Blood. 2012 May 10;119(19):4451-61. Epub 2012 Mar 28. PMID:22461490[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Gauthier-Campbell C, Bredt DS, Murphy TH, El-Husseini Ael-D. Regulation of dendritic branching and filopodia formation in hippocampal neurons by specific acylated protein motifs. Mol Biol Cell. 2004 May;15(5):2205-17. Epub 2004 Feb 20. PMID:14978216 doi:10.1091/mbc.E03-07-0493
- ↑ Oceguera-Yanez F, Kimura K, Yasuda S, Higashida C, Kitamura T, Hiraoka Y, Haraguchi T, Narumiya S. Ect2 and MgcRacGAP regulate the activation and function of Cdc42 in mitosis. J Cell Biol. 2005 Jan 17;168(2):221-32. Epub 2005 Jan 10. PMID:15642749 doi:10.1083/jcb.200408085
- ↑ Modzelewska K, Newman LP, Desai R, Keely PJ. Ack1 mediates Cdc42-dependent cell migration and signaling to p130Cas. J Biol Chem. 2006 Dec 8;281(49):37527-35. Epub 2006 Oct 12. PMID:17038317 doi:10.1074/jbc.M604342200
- ↑ Harada Y, Tanaka Y, Terasawa M, Pieczyk M, Habiro K, Katakai T, Hanawa-Suetsugu K, Kukimoto-Niino M, Nishizaki T, Shirouzu M, Duan X, Uruno T, Nishikimi A, Sanematsu F, Yokoyama S, Stein JV, Kinashi T, Fukui Y. DOCK8 is a Cdc42 activator critical for interstitial dendritic cell migration during immune responses. Blood. 2012 May 10;119(19):4451-61. Epub 2012 Mar 28. PMID:22461490 doi:10.1182/blood-2012-01-407098
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