Actin Dynamics Control SRF Activity by Regulation of Its Coactivator MAL

  title={Actin Dynamics Control SRF Activity by Regulation of Its Coactivator MAL},
  author={Francesc Miralles and Guido Posern and A. Zaromytidou and Richard Treisman},

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The nuclear import mechanism of SRF co-activator MKL1

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Findings demonstrate that RhoA signaling pathways are able to regulate transcription in neurons by triggering translocation of the SRF co‐activator MAL.

Filamin A interacts with the coactivator MKL1 to promote the activity of the transcription factor SRF and cell migration

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Mutant actins that stabilise F‐actin use distinct mechanisms to activate the SRF coactivator MAL

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The role of the transcriptional coactivator MAL and its target genes in cell motility and EMT

The findings suggest a role of actin-MAL-SRF signaling in cell motility and that MAL is implicated in antimigratory responses through upregulation of the cytoskeleton-associated proteins Integrin α5, PKP2 and FHL1 in non-invasive cells.

Functional interactions between phosphatase POPX2 and mDia modulate RhoA pathways

It is proposed that the interaction between mDia1 and POPX2 (PPM1F) serves to regulate both the actin cytoskeleton and SRF-mediated transcription, and to link the CDC42/RAC1 pathways with those of RhoA.

RASSF1A is required for the maintenance of nuclear actin levels

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Mutant actins demonstrate a role for unpolymerized actin in control of transcription by serum response factor.

Results provide strong evidence that G-actin, or a subpopulation of it, plays a direct role in signal transduction to SRF.

LIM kinase and Diaphanous cooperate to regulate serum response factor and actin dynamics

A role for LIMK in SRF activation, and functional cooperation between RhoA-controlled LIMK and mDia effector pathways are demonstrated.

The diaphanous-related formin mDia1 controls serum response factor activity through its effects on actin polymerization.

It is shown that the ability of mDia1 to potentiate SRF activity is strictly correlated with its ability to promote F-actin assembly, and that it regulatesSRF activity by inducing depletion of the cellular pool of G-Actin.

Smooth Muscle Differentiation Marker Gene Expression Is Regulated by RhoA-mediated Actin Polymerization*

The results of these studies indicate that in SMC, RhoA-dependent regulation of the actin cytoskeleton selectively regulates SMC differentiation marker gene expression by modulating SRF-dependent transcription and suggest that RHoA signaling may serve as a convergence point for the multiple signaling pathways that regulate SMC differentiate.

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