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Castrillon, D. H. & Wasserman, S. A. Diaphanous is required for cytokinesis in Drosophila and shares domains of similarity with the products of the limb deformity gene. Development 120, 3367-3377

Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas 75235-9038.
Development (Impact Factor: 6.27). 01/1995; 120(12):3367-77.
Source: PubMed

ABSTRACT We show that the Drosophila gene diaphanous is required for cytokinesis. Males homozygous for the dia1 mutation are sterile due to a defect in cytokinesis in the germline. Females trans-heterozygous for dia1 and a deficiency are sterile and lay eggs with defective eggshells; failure of cytokinesis is observed in the follicle cell layer. Null alleles are lethal. Death occurs at the onset of pupation due to the absence of imaginal discs. Mitotic figures in larval neuroblasts were found to be polyploid, apparently due to a defect in cytokinesis. The predicted 123 x 10(3) M(r) protein contains two domains shared by the formin proteins, encoded by the limb deformity gene in the mouse. These formin homology domains, which we have termed FH1 and FH2, are also found in Bni1p, the product of a Saccharomyces cerevisiae gene required for normal cytokinesis in diploid yeast cells.

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    • "In this way, ECT2 drives the highly localized activation of RhoA and forms a signal for cytokinesis. Once activated, RhoA is then thought to recruit effector proteins, including the formin diaphanous and one or more members of the Rho kinase family (Castrillon and Wasserman, 1994; Madaule et al., 1998; Hickson et al., 2006; Bassi et al., 2011). "
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    • "The authors have initially named this gene jazigo (jaz), which stands for ''grave'' in Brazilian Portuguese. Bioinformatic analysis revealed that the CG32030 locus encodes putative actin binding proteins sharing similarity with the formin family of proteins (Castrillon and Wasserman, 1994; Chesarone et al., 2010). Later, due to its similarity to the FHOS subfamily of mammalian formins, BDGP/Flybase reannotated the gene as Fhos. "
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    • "Additional PLP-biding ligands are the formin-related proteins, S. cerevisiae Bni1p and Bnr1p, S. pombe Cdc12p, Drosophila cappuccino and p140mDia, the mammalian homologue of the Drosophila protein diaphanous (Chang et al., 1997; Evangelista et al., 1997; Imamura et al., 1997; Manseau et al., 1996; Watanabe et al., 1997). These proteins have a proline-rich domain with numerous proline stretches consisting of 5–13 residues and a C-terminal consensus sequence of approximately 100 amino acids (Castrillon & Wasserman, 1994). Due to the high specific binding of Bni1p, Bnr1p and p140mDia to the GTP-bound form of Rho family members (Kohno et al., 1996; Imamura et al., 1997; Watanabe et al., 1997); they perhaps represent significant connectors between signal transduction, profilin and the cytoskeleton. "
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