Expression of formin FH1–FH2 derivatives that induce stress fiber formation also induce activation of an SRF reporter gene.

<p><b>A</b>) NIH 3T3 fibroblasts were transiently transfected with an SRF luciferase reporter gene and the indicated formin FH1FH2 derivative. Formin derivatives that induce stress fiber formation also induce activation of the SRF reporter gene. Expression of FHOD1, FHOD3 and Fmn1 FH1FH2 derivatives fail to induce robust activation of the SRF reporter consistent with their effects on stress fiber formation. Reporter activation is expressed relative to an SRF-VP16 control fusion protein. N = 4, error bars = SEM. <b>B</b>) Equivalent samples of transfected cell lysates from (A) were subjected to SDS-PAGE and immunoblotted to detect the myc epitope tag on the expressed formin proteins; lane order matches the order in (A).