Self-assembly mechanism for rearrangement of actin cytoskeleton in cell polarization

• Project/Area Number: 24770146
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Biophysics
• Research Institution: Tohoku University
• Principal Investigator: KIUCHI TAI 東北大学, 生命科学研究科, 助教 (70443984)
• Project Period (FY): 2012-04-01 – 2014-03-31
• Project Status: Completed (Fiscal Year 2013)
• Budget Amount: ¥4,680,000 (Direct Cost: ¥3,600,000、Indirect Cost: ¥1,080,000); Fiscal Year 2013: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000); Fiscal Year 2012: ¥2,730,000 (Direct Cost: ¥2,100,000、Indirect Cost: ¥630,000)
• Keywords: バイオイメージング / アクチン細胞骨格 / アクチンダイナミクス / アクチン

Research Abstract

The self-assembly mechanism for rearrangement of actin cytoskeleton plays important roles in cell polarization. In this study, I investigated the mechanosensitive rearrangement of actin cytoskeleton by an actin polymerization factor, mDia1. Fluorescence single-molecule speckle microscopy show that processive actin assembly by mDia1 is stimulated by microneedle micromanipulation. This mDia1 activation is suppressed by inactivation of an actin depolymerization factor, cofilin. s-FDAP analysis show that its cytoplasmic actin monomer concentration is increased by about 10% after the micromanipulation. These results suggest a self-assembly system including a micromanipulation-induced actin disassembly, an increase in the actin monomer concentration, processive actin assembly by mDia1 and the rearrangement of actin cytoskeleton.

Research Products

• [Journal Article] A new single-molecule speckle microscopy reveals modification of the retrograde actin flow by focal adhesions at nanometer scales. (2014)
  • Author(s): Yamashiro S, Mizuno H, Smith MB, Ryan GL, Kiuchi T, Vavylonis D, Watanabe N
  • Journal Title: Molecular Biology of the Cell Volume: 25 Issue: 7 Pages: 1010-1024
  • DOI: 10.1091/mbc.e13-03-0162
  • Peer Reviewed
• [Journal Article] Molecular viewing of actin polymerizing actions and beyond: Combination analysis of single-molecule speckle microscopy with modeling, FRAP and s-FDAP (sequential fluorescence decay after photoactivation). (2013)
  • Author(s): Watanabe N*, Yamashiro S, Vavylonis D, Kiuchi T
  • Journal Title: Development, Growth & Differentiation Volume: 55 Issue: 4 Pages: 508-514
  • DOI: 10.1111/dgd.12060
  • NAID: 40019735169
  • Peer Reviewed
• [Journal Article] CaMKIIβ-mediated LIM-kinase activation plays a crucial role in BDNF-induced neuritogenesis (2013)
  • Author(s): Saito, A., Miyajima, K., Akatsuka, J., Kondo, H., Mashiko, T., Kiuchi, T., Ohashi, K.,Mizuno, K.
  • Journal Title: Genes Cells Volume: (in press) Issue: 7 Pages: 533-543
  • DOI: 10.1111/gtc.12054
  • Peer Reviewed
• [Journal Article] 蛍光単分子可視化と他の分子動態解析法の融合による細胞内アクチン重合機構の解明 (2013)
  • Author(s): 渡邊直樹,木内泰
  • Journal Title: 顕微鏡 Volume: 第48巻第2号 Pages: 84-89
  • NAID: 10031194751
  • Peer Reviewed
• [Journal Article] F and G-actin homeostasis regulates mechanosensitive actin nucleation by formins (2013)
  • Author(s): Higashida C, Kiuchi T, Akiba Y, Mizuno H, Maruoka M, Narumiya S, Mizuno K, Watanabe N
  • Journal Title: Nature Cell Biol Volume: 15(4) Issue: 4 Pages: 395-405
  • DOI: 10.1038/ncb2693
  • Peer Reviewed
• [Journal Article] Distributed actin turnover in the lamellipodium and FRAP kinetics (2013)
  • Author(s): Smith MB, Kiuchi T, Watanabe N, Vavylonis D
  • Journal Title: Biophysical Journal Volume: vol. 104 Issue: 1 Pages: 247-257
  • DOI: 10.1016/j.bpj.2012.11.3819
  • Peer Reviewed