Structural highlights
Function
DLG1_DROME During embryonic development, some isoforms are essential for proper neuronal differentiation and organization. Required for cell polarity; maintenance of apicobasal polarity. Plays a critical role at septate junctions in cellular growth control during larval development. The presence of a guanylate kinase domain suggests involvement in cellular adhesion as well as signal transduction to control cellular proliferation.[1] [2] [3]
Publication Abstract from PubMed
Disc large 1 (Dlg1) proteins, members of the MAGUK protein family, are linked to cell polarity via their participation in multiprotein assemblies. At their N-termini, Dlg1 proteins contain a L27 domain. Typically, the L27 domains participate in the formation of obligate hetero-oligomers with the L27 domains from their cognate partners. Among the MAGUKs, Dlg1 proteins exist as homo-oligomers, and the oligomerization is solely dependent on the L27 domain. Here we provide biochemical and structural evidence of homodimerization via the L27 domain of Dlg1 from Drosophila melanogaster. The structure reveals that the core of the dimer is formed by a distinctive six-helix assembly, involving all three conserved helices from each subunit (monomer). The homodimer interface is extended by the C-terminal tail of the L27 domain of Dlg1, which forms a two-stranded antiparallel beta-sheet. The structure reconciles and provides a structural context for a large body of available mutational data. From our analyses, we conclude that the observed L27 homodimerization is most likely a feature unique to the Dlg1 orthologs within the MAGUK family.
Structures of the L27 Domain of Disc Large Homologue 1 Protein Illustrate a Self-Assembly Module.,Ghosh A, Ramagopal UA, Bonanno JB, Brenowitz M, Almo SC Biochemistry. 2018 Feb 27;57(8):1293-1305. doi: 10.1021/acs.biochem.7b01074. Epub, 2018 Feb 7. PMID:29261291[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Bilder D, Li M, Perrimon N. Cooperative regulation of cell polarity and growth by Drosophila tumor suppressors. Science. 2000 Jul 7;289(5476):113-6. PMID:10884224
- ↑ Mendoza C, Olguin P, Lafferte G, Thomas U, Ebitsch S, Gundelfinger ED, Kukuljan M, Sierralta J. Novel isoforms of Dlg are fundamental for neuronal development in Drosophila. J Neurosci. 2003 Mar 15;23(6):2093-101. PMID:12657668
- ↑ Woods DF, Bryant PJ. The discs-large tumor suppressor gene of Drosophila encodes a guanylate kinase homolog localized at septate junctions. Cell. 1991 Aug 9;66(3):451-64. PMID:1651169
- ↑ Ghosh A, Ramagopal UA, Bonanno JB, Brenowitz M, Almo SC. Structures of the L27 Domain of Disc Large Homologue 1 Protein Illustrate a Self-Assembly Module. Biochemistry. 2018 Feb 27;57(8):1293-1305. doi: 10.1021/acs.biochem.7b01074. Epub, 2018 Feb 7. PMID:29261291 doi:http://dx.doi.org/10.1021/acs.biochem.7b01074
