6M4C

C. albicans actin interacting protein Aip5

Summary for 6M4C

• Entry DOI: 10.2210/pdb6m4c/pdb
• Descriptor: C. albicans actin interacting protein Aip5 (2 entities in total)
• Functional Keywords: actin, polarisome, cytosolic protein, nucleation promoting factor
• Biological source: Candida albicans SC5314 (Yeast)
• Total number of polymer chains: 1
• Total formula weight: 11312.71

Authors

Loh, Z.Y.,Gao, Y.G.,Xie, Y.,Miao, Y. (deposition date: 2020-03-06, release date: 2020-08-26, Last modification date: 2023-11-29)

Primary citation

Xie, Y.,Loh, Z.Y.,Xue, J.,Zhou, F.,Sun, J.,Qiao, Z.,Jin, S.,Deng, Y.,Li, H.,Wang, Y.,Lu, L.,Gao, Y.,Miao, Y.
Orchestrated actin nucleation by the Candida albicans polarisome complex enables filamentous growth.
J.Biol.Chem., 295:14840-14854, 2020

PubMed Abstract: is a dimorphic fungus that converts from a yeast form to a hyphae form during infection. This switch requires the formation of actin cable to coordinate polarized cell growth. It's known that nucleation of this cable requires a multiprotein complex localized at the tip called the polarisome, but the mechanisms underpinning this process were unclear. Here, we found that Aip5, a homolog of polarisome component ScAip5 in that nucleates actin polymerization and synergizes with the formin ScBni1, regulates actin assembly and hyphae growth synergistically with other polarisome proteins Bni1, Bud6, and Spa2. The C terminus of Aip5 binds directly to G-actin, Bni1, and the C-terminal of Bud6, which form the core of the nucleation complex to polymerize F-actin. Based on insights from structural biology and molecular dynamic simulations, we propose a possible complex conformation of the actin nucleation core, which provides cooperative positioning and supports the synergistic actin nucleation activity of a tri-protein complex Bni1-Bud6-Aip5. Together with known interactions of Bni1 with Bud6 and Aip5 in , our findings unravel molecular mechanisms of by which the tri-protein complex coordinates the actin nucleation in actin cable assembly and hyphal growth, which is likely a conserved mechanism in different filamentous fungi and yeast.

PubMed: 32848016
DOI: 10.1074/jbc.RA120.013890

Experimental method

X-RAY DIFFRACTION (2.65 Å)