血管新生における力の機能についての研究

• Project/Area Number: 15F14385
• Research Category: Grant-in-Aid for JSPS Fellows
• Allocation Type: Single-year Grants
• Section: 外国
• Research Field: Cell biology
• Research Institution: National Cardiovascular Center Research Institute
• Principal Investigator: 望月 直樹 国立研究開発法人国立循環器病研究センター, 研究所, 副所長 (30311426)
• Co-Investigator(Kenkyū-buntansha): PHNG LI-KUN 国立研究開発法人国立循環器病研究センター, 研究所, 外国人特別研究員
• Project Period (FY): 2015-04-24 – 2018-03-31
• Project Status: Granted (Fiscal Year 2016)
• Budget Amount: ¥2,200,000 (Direct Cost: ¥2,200,000); Fiscal Year 2016: ¥1,100,000 (Direct Cost: ¥1,100,000); Fiscal Year 2015: ¥1,100,000 (Direct Cost: ¥1,100,000)
• Keywords: angiogenesis / endothelial cell / actin / Marcks1 / zebrafish / 血管新生 / 細胞骨格 / ミオシン / アクチン

Outline of Annual Research Achievements

I identified Marcksl1, an actin-binding protein, as a molecular regulator of endothelial cell cortex during blood vessel morphogenesis in the zebrafish embryo. During lumen formation, Marcksl1 localization is enriched in the apical membrane. Overexpression of the protein perturbed cell cortex integrity so that 1) excessive blebs form at the apical membrane during lumen expansion and 2) ectopic blebs from at the basal membrane in perfused vessels that dissipate after inhibiting blood flow. In addition, endothelial cells with increased Marcksl1 expression are irregular in shape so that they are more dilated than wild type cells. These findings suggest that Marcksl1 regulates endothelial cell cortex dynamics and strength and that a robust cortex is required to resist haemodynamic forces and maintain blood vessel structure.

Current Status of Research Progress

2: Research has progressed on the whole more than it was originally planned.

Reason

We aimed at identification of molecules that regulate lumen formation during angiogenesis. Marcks1 functions has been identified in our experiments. It regulates actin-bundling during lumen formation. Marcks1 is also involved in the establishment of apico-basal polarity. Therefore, the purpose of our research has been achieved. Moreover, using various probes for visualizing vascular structure, we have been able to observe the thin fillopodia during the extension of endothelial cells.

Strategy for Future Research Activity

To fully understand the function of Marcksl1 in blood vessel morphogenesis, it is important to study endothelial cell behavior in the absence of the protein. To this end, I have generated marcksl1a and marcksl1b double mutant zebrafish, which I will analyze for vascular phenotypes. In addition, I will determine how Marcksl1 regulates endothelial cell cortex by examining whether 1) its F-actin binding domain is required for its activity, 2) cortical tension is altered in endothelial cells with increased or decreased Marcksl1 expression and 3), it regulates the process of membrane bleb retraction.

Research Products

• [Int'l Joint Research] Max-Delbruck Center(Germany)
• [Journal Article] Blood flow drives lumen formation by inverse membrane blebbing during angiogenesis in vivo. (2016)
  • Author(s): Gebala V, Collins R, Geudens I, Phng LK, Gerhardt H
  • Journal Title: Nat. Cell Biol Volume: epub ahead Issue: 4 Pages: 443-451
  • DOI: 10.1038/ncb3320
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Correction: dynamic endothelial cell rearrangements drive developmental vessel regression. (2015)
  • Author(s): Franco CA, Jones ML, Bernabeu MO, Geudens I, Mathivet T, Rosa A, Lopes FM, Lima AP, Ragab A, Collins RT, Phng LK, Coveney PV, Gerhardt H.
  • Journal Title: Plos Biol. Volume: 13 Issue: 5 Pages: e1002163-e1002163
  • DOI: 10.1371/journal.pbio.1002163
  • Peer Reviewed / Open Access
• [Journal Article] Dynamic endothelial cell rearrangements drive developmental vessel regression. (2015)
  • Author(s): Franco CA, Jones ML, Bernabeu MO, Geudens I, Mathivet T, Rosa A, Lopes FM, Lima AP, Ragab A, Collins RT, Phng LK, Coveney PV, Gerhardt H.
  • Journal Title: Plos Biol. Volume: 13 Issue: 4 Pages: e1002125-e1002125
  • DOI: 10.1371/journal.pbio.1002125
  • Peer Reviewed / Open Access
• [Journal Article] Formin-mediated actin polymerization at endothelial junctions is required for vessel lumen formation and stabilization. (2015)
  • Author(s): Phng LK, Gebala V, Bentley K, Philippides A, Wacker A, Mathivet T, Sauteur L, Stanchi F, Belting HG, Affolter M, Gerhardt H.
  • Journal Title: Dev. Cell Volume: 32 Issue: 1 Pages: 123-132
  • DOI: 10.1016/j.devcel.2014.11.017
• [Presentation] Actin dynamics in lumen formation during sprouting angiogenesis (2016)
  • Author(s): Li-Kun Phng
  • Organizer: 22nd Japanese Medaka and Zebrafish Meeting
  • Place of Presentation: Okazaki JAPAN
  • Year and Date: 2016-08-20