Identification of a short Spir interaction sequence at the C-terminal end of formin subgroup proteins.
The actin nucleation factors Spire and Cappuccino interact with each other and regulate essential cellular events during Drosophila oogenesis in a cooperative fashion. The interaction blocks formin actin nucleation activity and enhances the Spire activity. Analogous to Spire and Cappuccino, the mammalian homologs Spir-1 and formin-2 show a regulatory interaction. To get an understanding of the nature of the Spir-formin cooperation, we have analyzed the interaction biochemically and biophysically. Our data shows that the association of Spir-1 and formin-2 is not significantly mediated by binding of the Spir-1-KIND domain to the formin FH2 core domain. Instead, a short sequence motif C-terminal adjacent to the formin-2-FH2 domain could be characterized that mediates the interaction and is conserved among the members of the Fmn subgroup of formins. In line with this, we found that both mammalian Spir proteins, Spir-1 and Spir-2, interact with mammalian Fmn subgroup proteins formin-1 and formin-2.
Pechlivanis
Markos
M
Bavarian Genome Research Network (BayGene), Cell Structure and Genomics, Institute of Functional Genomics, University of Regensburg, Franz-Josef-Strauss-Allee 11, 93053 Regensburg, Germany.
Samol
Annette
A
Kerkhoff
Eugen
E
D000595:Amino Acid Sequence; D000818:Animals; D016880:Anisotropy; D049109:Cell Proliferation; D005326:Fetal Proteins / Q000737:chemistry*; D000080865:Formins; D006367:HeLa Cells; D006801:Humans; D008840:Microfilament Proteins / Q000737:chemistry*; D008856:Microscopy, Fluorescence / Q000379:methods; D008954:Models, Biological; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000737:chemistry*; D009687:Nuclear Proteins / Q000737:chemistry*; D009866:Oogenesis; D017434:Protein Structure, Tertiary; D017386:Sequence Homology, Amino Acid
D005326:Fetal Proteins; D000080865:Formins; D008840:Microfilament Proteins; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins; C000592292:SPIRE1 protein, human