Transient α-helices in the disordered RPEL motifs of the serum response factor coactivator MKL1

  title={Transient $\alpha$-helices in the disordered RPEL motifs of the serum response factor coactivator MKL1},
  author={Mineyuki Mizuguchi and Takahiro Fuju and Takayuki Obita and Mitsuru Ishikawa and Masaaki Tsuda and Akiko Tabuchi},
  journal={Scientific Reports},
The megakaryoblastic leukemia 1 (MKL1) protein functions as a transcriptional coactivator of the serum response factor. MKL1 has three RPEL motifs (RPEL1, RPEL2, and RPEL3) in its N-terminal region. MKL1 binds to monomeric G-actin through RPEL motifs, and the dissociation of MKL1 from G-actin promotes the translocation of MKL1 to the nucleus. Although structural data are available for RPEL motifs of MKL1 in complex with G-actin, the structural characteristics of RPEL motifs in the free state… 
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