The Basic Region of the Diaphanous-autoregulatory Domain (DAD) Is Required for Autoregulatory Interactions with the Diaphanous-related Formin Inhibitory Domain

Wallar, B.J.; Stropich, Brittany N.; Schoenherr, Jessica A.; Holman, Holly A.; Kitchen, Susan M.; Alberts, Arthur S.

doi:10.1074/jbc.m510277200

Cited by 100 publications

(101 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Dia-inhibitory domain (DID) weakly binds to and inhibits the actin-nucleating formin homology-2 (FH2) domain (Li and Higgs, 2003). Dia-autoregulatory domain (DAD) acts as a high-affinity anchor or catch that is released on Rho binding to the GTPase-binding domain (Alberts, 2001;Wallar et al, 2006). Bound GTP-Rho sterically interferes with DAD binding, thus releasing the inhibitory effects of DID over actin assembly.…”

Section: Q-myelodysplastic Syndromesmentioning

confidence: 99%

“…Bound GTP-Rho sterically interferes with DAD binding, thus releasing the inhibitory effects of DID over actin assembly. This leads to activation of F-actin assembly and microtubule stabilization (Alberts, 2001;Palazzo et al, 2001;Wallar et al, 2006). (b) Spontaneous actin assembly progresses from monomers to actin dimers and trimers; in the absence of assembly factors, these quickly dissociate.…”

Section: Q-myelodysplastic Syndromesmentioning

confidence: 99%

See 1 more Smart Citation

5q– myelodysplastic syndromes: chromosome 5q genes direct a tumor-suppression network sensing actin dynamics

et al. 2009

View full text Add to dashboard Cite

Section: Q-myelodysplastic Syndromesmentioning

confidence: 99%

Section: Q-myelodysplastic Syndromesmentioning

confidence: 99%

5q– myelodysplastic syndromes: chromosome 5q genes direct a tumor-suppression network sensing actin dynamics

et al. 2009

View full text Add to dashboard Cite

“…Initially discovered in diaphanous-related formins, this mechanism relies on the interaction of a conserved C-terminal motif, named Diaphanous Autoregulatory Domain (DAD), with the Diaphanous Inhibitory Domain (DID) in the N-terminal region (Watanabe et al, 1999;Alberts, 2001;Higgs, 2003, 2004;Wallar et al, 2006). Support for this model largely came from the observation that exogenous expression of truncated formin constructs, lacking either N or C terminus, or harboring a mutated DAD region, led to an overabundance of actin structures, such as filopodia or stress fibers (Watanabe et al, 1999;Tominaga et al, 2000;Koka et al, 2003;Schonichen et al, 2006;Wallar et al, 2006). It is not clear whether all formins use an autoinhibitory mechanism for regulation, because many formins do not contain an obvious DAD-like sequence at the primary sequence level (Higgs and Peterson, 2004).…”

Section: Introductionmentioning

confidence: 99%

Regulation of the Formin for3p by cdc42p and bud6p

Martin

Rincón

Basu

et al. 2007

MBoC

138

167

View full text Add to dashboard Cite

Formins are conserved actin nucleators responsible for the assembly of diverse actin structures. Many formins are controlled through an autoinhibitory mechanism involving the interaction of a C-terminal DAD sequence with an N-terminal DID sequence. Here, we show that the fission yeast formin for3p, which mediates actin cable assembly and polarized cell growth, is regulated by a similar autoinhibitory mechanism in vivo. Multiple sites govern for3p localization to cell tips. The localization and activity of for3p are inhibited by an intramolecular interaction of divergent DAD and DID-like sequences. A for3p DAD mutant expressed at endogenous levels produces more robust actin cables, which appear to have normal organization and dynamics. We identify cdc42p as the primary Rho GTPase involved in actin cable assembly and for3p regulation. Both cdc42p, which binds at the N terminus of for3p, and bud6p, which binds near the C-terminal DAD-like sequence, are needed for for3p localization and full activity, but a mutation in the for3p DAD restores for3p localization and other phenotypes of cdc42 and bud6 mutants. In particular, the for3p DAD mutation suppresses the bipolar growth (NETO) defect of bud6⌬ cells. These findings suggest that cdc42p and bud6p activate for3p by relieving autoinhibition. INTRODUCTIONFormins are key regulators of the actin cytoskeleton and form a large family conserved in all eukaryotes Faix and Grosse, 2006). These proteins are necessary for the formation of numerous actin structures, including stress fibers, filopodia, cytokinetic actin rings, junctional actin structures, or actin cables. The proper regulation of formins is likely to be critical for cellular processes such as cell migration, cytokinesis, cell adhesion, and cell polarity.A well characterized biochemical activity of formins is to nucleate and elongate linear actin filaments Sagot et al., 2002b;Kovar et al., 2003;Li and Higgs, 2003;Moseley et al., 2004). This activity occurs through the formin-homology (FH) 2 domain, which dimerizes to form a doughnut-shaped structure containing multiple actin-binding sites in its core Otomo et al., 2005b). This dimer is thought to stabilize otherwise unstable intermediates in the assembly of new actin filaments, and it binds processively to the fast-elongating barbed end of existing actin filaments (Pring et al., 2003;Kovar and Pollard, 2004).The adjacent FH1 domain binds profilin-actin and helps accelerate the elongation of actin filaments (Chang et al., 1997;Evangelista et al., 1997;Watanabe et al., 1997;Romero et al., 2004;Kovar et al., 2006). The budding yeast formin Bni1p also binds the actin monomer-binding protein Bud6p, which, similar to profilin, stimulates the activity of the FH2 domain (Moseley and Goode, 2005). In addition to their activity in actin filament nucleation and elongation, some formins have been suggested to also function in actin bundling and severing, further contributing to the remodeling of actin structures (Harris et al., 2004Moseley and Goode, 2005;Harris et al., 2006...

show abstract

“…The actin nucleation activity of formin proteins is regulated by an inhibitory interaction between the N-and C-terminal domains, which can be released when GTP-bound Rho protein binds to the formin N-terminal domain, allowing access of the C terminus (FH1-COOH) to actin filament barbed ends (31)(32)(33)(34)(35)(36)(37)(38)(39)(40). In yeast, the formin Bni1 N terminus also has an inhibitory effect on actin nucleation through binding to the C terminus (41).…”

mentioning

confidence: 99%

Cell-cycle regulation of formin-mediated actin cable assembly

Miao

Wong

Mennella

et al. 2013

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Assembly of appropriately oriented actin cables nucleated by formin proteins is necessary for many biological processes in diverse eukaryotes. However, compared with knowledge of how nucleation of dendritic actin filament arrays by the actin-related protein-2/3 complex is regulated, the in vivo regulatory mechanisms for actin cable formation are less clear. To gain insights into mechanisms for regulating actin cable assembly, we reconstituted the assembly process in vitro by introducing microspheres functionalized with the C terminus of the budding yeast formin Bni1 into extracts prepared from yeast cells at different cell-cycle stages. EM studies showed that unbranched actin filament bundles were reconstituted successfully in the yeast extracts. Only extracts enriched in the mitotic cyclin Clb2 were competent for actin cable assembly, and cyclin-dependent kinase 1 activity was indispensible. Cyclin-dependent kinase 1 activity also was found to regulate cable assembly in vivo. Here we present evidence that formin cellcycle regulation is conserved in vertebrates. The use of the cablereconstitution system to test roles for the key actin-binding proteins tropomyosin, capping protein, and cofilin provided important insights into assembly regulation. Furthermore, using mass spectrometry, we identified components of the actin cables formed in yeast extracts, providing the basis for comprehensive understanding of cable assembly and regulation.Cdk1 | three-dimensional structured-illumination microscopy | actin nucleation E ukaryotic cells contain populations of actin structures with distinct architectures and protein compositions, which mediate varied cellular processes (1). Understanding how F-actin polymerization is regulated in time and space is critical to understanding how actin structures provide mechanical forces for corresponding biological processes. Branched actin filament arrays, which concentrate at sites of clathrin-mediated endocytosis (2, 3) and at the leading edge of motile cells (4), are nucleated by the actin-related protein-2/3 (Arp2/3) complex. In contrast, bundles of unbranched actin filaments, which sometimes mediate vesicle trafficking or form myosin-containing contractile bundles, often are nucleated by formin proteins (5-14).Much has been learned about how branched actin filaments are polymerized by the Arp2/3 complex and how these filaments function in processes such as endocytosis (2, 15). In contrast, relatively little is known about how actin cables are assembled under physiological conditions. In previous studies, branched actin filaments derived from the Arp2/3 complex have been reconstituted using purified proteins (16)(17)(18)(19) or cellular extracts (20-25). When microbeads were coated with nucleation-promoting factors for the Arp2/3 complex and then were incubated in cell extracts, actin comet tails were formed by sequential actin nucleation, symmetry breaking, and tail elongation. Importantly, the motility behavior of F-actin assembled by the Arp2/3 complex using defined, purified pr...

show abstract

The Basic Region of the Diaphanous-autoregulatory Domain (DAD) Is Required for Autoregulatory Interactions with the Diaphanous-related Formin Inhibitory Domain

Cited by 100 publications

References 32 publications

5q– myelodysplastic syndromes: chromosome 5q genes direct a tumor-suppression network sensing actin dynamics

5q– myelodysplastic syndromes: chromosome 5q genes direct a tumor-suppression network sensing actin dynamics

Regulation of the Formin for3p by cdc42p and bud6p

Cell-cycle regulation of formin-mediated actin cable assembly

Contact Info

Product

Resources

About