Structural studies of septin heteromeric coiled-coils by nuclear magnetic resonance spectroscopy

• Grant number: 18/19992-7
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Effective date (Start): February 01, 2019
• Effective date (End): December 17, 2023
• Field of knowledge: Biological Sciences - Biophysics - Molecular Biophysics
• Principal Investigator: Richard Charles Garratt
• Grantee: Italo Augusto Cavini
• Host Institution: Instituto de Física de São Carlos (IFSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Associated research grant: 20/02897-1 - Septin filaments: structure, polymerization and role in pathologies, AP.TEM
• Associated scholarship(s): 22/00262-4 - Structural studies on heteromeric septin coiled coils by high-resolution nuclear magnetic resonance spectroscopy, BE.EP.PD

Abstract

Septins constitute a conserved guanine-binding protein family which are involved in several cellular processes and are capable of self-assembling into heterofilaments and high-order complexes. The human septins are encoded by 13 different genes and are divided into four groups based on their similarity. The C-terminal domain of septins contains characteristic repeats of alpha-helix coiled-coils whose importance in the formation and/or maintenance of complexes is still not fully understood. To date, the first and only crystallographic structure of a septin heterocomplex, the heterofilament SEPT2-6-7 published in 2007, does not contain information on the C-terminal domains - because of the absence of electron density in these regions. The current project proposes to obtain structural information on the C-terminal domains of SEPT6 (and others of its group as SEPT8, 10, 11 and 14) and SEPT7 using nuclear magnetic resonance and X-ray crystallography techniques. Among our objectives, we aim to determine interaction patterns that stabilize the interface of the SEPT6C-7C coiled-coil heterodimer and give selectivity to the heterofilament assembly. With nuclear magnetic resonance spectroscopy, we expect to obtain eNOEs, interproton distances up to 5 Å, that will indicate the relative orientation of the heterodimer and allow solving its structure in solution. In parallel, crystallographic assays will be performed to obtain a three-dimensional model also by X-ray diffraction. A better structural knowledge of the C-terminal domains will certainly shed light on how septins organize and also on the reason why different isoforms exist in some organisms.

Scientific publications

(4)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

FERNANDES, ADRIANO DE FREITAS; LEONARDO, DIEGO ANTONIO; CAVINI, ITALO AUGUSTO; ROSA, HIGOR VINICIUS DIAS; VARGAS, JHON ANTONI; PEREIRA, HUMBERTO D'MUNIZ; NASCIMENTO, ALESSANDRO S.; GARRATT, RICHARD CHARLES. Conservation and divergence of the G-interfaces of Drosophila melanogaster septins. CYTOSKELETON, v. N/A, p. 16-pg., 2023-01-03. (14/15546-1, 19/22000-9, 20/03983-9, 17/18173-0, 20/02897-1, 18/19992-7, 21/08158-9)

CAVINI, ITALO A.; LEONARDO, DIEGO A.; ROSA, HIGOR V. D.; CASTRO, DANIELLE K. S. V.; D'MUNIZ PEREIRA, HUMBERTO; VALADARES, NAPOLEAO F.; ARAUJO, ANA P. U.; GARRATT, RICHARD C.. The Structural Biology of Septins and Their Filaments: An Update. FRONTIERS IN CELL AND DEVELOPMENTAL BIOLOGY, v. 9, NOV 19 2021. (14/15546-1, 18/19992-7, 20/02897-1, 16/04658-9, 19/22000-9)

LEONARDO, DIEGO A.; CAVINI, ITALO A.; SALA, FERNANDA A.; MENDONCA, DEBORAH C.; ROSA, HIGOR V. D.; KUMAGAI, PATRICIA S.; CRUSCA JR, EDSON; VALADARES, NAPOLEAO F.; MARQUES, IVO A.; BRANDAO-NETO, JOSE; et al. Orientational Ambiguity in Septin Coiled Coils and its Structural Basis. Journal of Molecular Biology, v. 433, n. 9, APR 30 2021. (18/20209-5, 16/04658-9, 17/07709-6, 19/22000-9, 14/15546-1, 15/00062-1, 13/04433-9, 15/16811-3, 18/19992-7)

CASTRO, DANIELLE K. S. V.; ROSA, HIGOR V. D.; MENDONC, DEBORAH C.; CAVINI, ITALO A.; ARAUJO, ANA P. U.; GARRATT, RICHARD C.. Dissecting the Binding Interface of the Septin Polymerization Enhancer Borg BD3. Journal of Molecular Biology, v. 435, n. 13, p. 16-pg., 2023-05-10. (14/15546-1, 18/20209-5, 18/19992-7, 20/02897-1)