3dmk

Structural highlights

Function

DSCA1_DROME Cell surface receptor involved in guidance and targeting of growing nerve axons (PubMed:10892653). Required during Bolwig's organ differentiation for accurate and efficient targeting of photoreceptor neuron axons to their synaptic targets in the brain via the P2 intermediate target neuron (PubMed:10892653). Involved in isoneural self-avoidance during dendrite arborization but not in heteroneural recognition and repulsion during tiling by related neurons of the same class (PubMed:17482551). Involved in regulating axon bifurcation and divergent extension in the developing mushroom body (PubMed:11856530, PubMed:15339648). Essential for axon arborisation in ellipsoid body (PubMed:11856530, PubMed:15339648). Exhibits an extraordinary level of molecular diversity resulting from alternative splicing (PubMed:10892653). Isoforms differing in their ectodomain makeup show a high degree of functional redundancy while isoforms with different transmembrane domains are involved in different neuronal morphogenetic processes and are differentially targeted to dendrites or axons (PubMed:15339648). The vast majority of isoforms exhibit strong isoform-specific homophilic binding (PubMed:15339666, PubMed:17889655). Individual cells express a distinct randomly generated repertoire of isoforms (PubMed:14758360). Cell surfaces bearing identical repertoires of Dscam1 isoforms, such as those from the same cell, trigger recognition and avoidance (PubMed:17482551). A subset of isoforms is expressed in fat body cells and hemocytes, cells that are part of the insect immune response, and these isoforms are secreted into the hemolymph (PubMed:16109846). The secreted form comprising the ectodomain can bind to bacteria, such as Escherichia coli, and may act as an opsonin enhancing their phagocytosis by hemocytes (PubMed:16109846).^{[1] [2] [3] [4] [5] [6] [7] [8]}

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

References

1. ↑ Schmucker D, Clemens JC, Shu H, Worby CA, Xiao J, Muda M, Dixon JE, Zipursky SL. Drosophila Dscam is an axon guidance receptor exhibiting extraordinary molecular diversity. Cell. 2000 Jun 9;101(6):671-84. PMID:10892653 doi:10.1016/s0092-8674(00)80878-8
2. ↑ Wang J, Zugates CT, Liang IH, Lee CH, Lee T. Drosophila Dscam is required for divergent segregation of sister branches and suppresses ectopic bifurcation of axons. Neuron. 2002 Feb 14;33(4):559-71. PMID:11856530 doi:10.1016/s0896-6273(02)00570-6
3. ↑ Neves G, Zucker J, Daly M, Chess A. Stochastic yet biased expression of multiple Dscam splice variants by individual cells. Nat Genet. 2004 Mar;36(3):240-6. PMID:14758360 doi:10.1038/ng1299
4. ↑ Wang J, Ma X, Yang JS, Zheng X, Zugates CT, Lee CH, Lee T. Transmembrane/juxtamembrane domain-dependent Dscam distribution and function during mushroom body neuronal morphogenesis. Neuron. 2004 Sep 2;43(5):663-72. PMID:15339648 doi:10.1016/j.neuron.2004.06.033
5. ↑ Wojtowicz WM, Flanagan JJ, Millard SS, Zipursky SL, Clemens JC. Alternative splicing of Drosophila Dscam generates axon guidance receptors that exhibit isoform-specific homophilic binding. Cell. 2004 Sep 3;118(5):619-33. PMID:15339666 doi:10.1016/j.cell.2004.08.021
6. ↑ Watson FL, Püttmann-Holgado R, Thomas F, Lamar DL, Hughes M, Kondo M, Rebel VI, Schmucker D. Extensive diversity of Ig-superfamily proteins in the immune system of insects. Science. 2005 Sep 16;309(5742):1874-8. PMID:16109846 doi:10.1126/science.1116887
7. ↑ Matthews BJ, Kim ME, Flanagan JJ, Hattori D, Clemens JC, Zipursky SL, Grueber WB. Dendrite self-avoidance is controlled by Dscam. Cell. 2007 May 4;129(3):593-604. PMID:17482551 doi:10.1016/j.cell.2007.04.013
8. ↑ Wojtowicz WM, Wu W, Andre I, Qian B, Baker D, Zipursky SL. A vast repertoire of Dscam binding specificities arises from modular interactions of variable Ig domains. Cell. 2007 Sep 21;130(6):1134-45. PMID:17889655 doi:10.1016/j.cell.2007.08.026
9. ↑ Sawaya MR, Wojtowicz WM, Andre I, Qian B, Wu W, Baker D, Eisenberg D, Zipursky SL. A double S shape provides the structural basis for the extraordinary binding specificity of Dscam isoforms. Cell. 2008 Sep 19;134(6):1007-18. PMID:18805093 doi:10.1016/j.cell.2008.07.042