Molecular mechanism of glutaminase activation through filamentation and the role of filaments in mitophagy protection

Author(s):Show less -

Adamoski, Douglas ; Dias, Marilia Meira ; Quesnay, Jose Edwin Neciosup ; Yang, Zhengyi ; Zagoriy, Ievgeniia ; Steyer, Anna M. ; Rodrigues, Camila Tanimoto ; da Silva Bastos, Alliny Cristiny ; da Silva, Bianca Novaes ; Costa, Renna Karoline Eloi ; de Abreu, Flavia Mayumi Odahara ; Islam, Zeyaul ; Cassago, Alexandre ; van Heel, Marin Gerard ; Consonni, Silvio Roberto ; Mattei, Simone ; Mahamid, Julia ; Portugal, Rodrigo Villares ; Ambrosio, Andre Luis Berteli ; Dias, Sandra Martha Gomes

• Document type: Journal article
• Source: NATURE STRUCTURAL & MOLECULAR BIOLOGY; v. 30, n. 12, p. 33-pg., 2023-10-19.

Abstract

Glutaminase (GLS), which deaminates glutamine to form glutamate, is a mitochondrial tetrameric protein complex. Although inorganic phosphate (Pi) is known to promote GLS filamentation and activation, the molecular basis of this mechanism is unknown. Here we aimed to determine the molecular mechanism of Pi-induced mouse GLS filamentation and its impact on mitochondrial physiology. Single-particle cryogenic electron microscopy revealed an allosteric mechanism in which Pi binding at the tetramer interface and the activation loop is coupled to direct nucleophile activation at the active site. The active conformation is prone to enzyme filamentation. Notably, human GLS filaments form inside tubulated mitochondria following glutamine withdrawal, as shown by in situ cryo-electron tomography of cells thinned by cryo-focused ion beam milling. Mitochondria with GLS filaments exhibit increased protection from mitophagy. We reveal roles of filamentous GLS in mitochondrial morphology and recycling. (AU)

• FAPESP's process: 17/15340-2 - EMU: acquisition of a transmission electron microscope for single particle cryo electron microscopy - establishing a cryo electron microscopy open facility at CNPEM
• Grantee: Rodrigo Villares Portugal
• Support Opportunities: Multi-user Equipment Program
• FAPESP's process: 17/11766-5 - Biophysical and biochemical studies of transmembrane mitochondrial proteins and their implication on the tumor metabolism adaptation process
• Grantee: Andre Luis Berteli Ambrosio
• Support Opportunities: Regular Research Grants
• FAPESP's process: 21/01504-9 - Effects of parity and age on chondrogenesis and osteogenesis of the pubic symphysis in mice: a morphological and molecular approach to potential risk factors for pelvic organ prolapse
• Grantee: Sílvio Roberto Consonni
• Support Opportunities: Regular Research Grants
• FAPESP's process: 21/03933-4 - Cryo-EM structural studies on the Xanthomonadaceae type IV secretion systems
• Grantee: José Edwin Neciosup Quesñay
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 14/12663-7 - Biophysical and biochemical studies of the human glutaminases in complex with novel binding partners
• Grantee: Zeyaul Islam
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 19/16351-3 - The glutaminase role on tumor progression
• Grantee: Sandra Martha Gomes Dias
• Support Opportunities: Regular Research Grants
• FAPESP's process: 21/13736-1 - Functional impact of the glutaminase enzyme interaction with pyruvate kinase M2 in the tumor microenvironment
• Grantee: Bianca Novaes da Silva
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• FAPESP's process: 16/09077-4 - Developing new glutaminase inhibitors with potential anti-tumor activity
• Grantee: Renna Karoline Eloi Costa
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• FAPESP's process: 14/20673-2 - Biophysical and biochemical studies of the mitochondrial pyruvate carrier (MPC) complex and the glutaminase enzyme bound to novel partners
• Grantee: Andre Luis Berteli Ambrosio
• Support Opportunities: Regular Research Grants
• FAPESP's process: 20/06062-1 - Biological complexes in action, in vitro and in silico (Exploiting Big-Data in Cryo-EM)
• Grantee: Marin Gerard van Heel
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 13/07600-3 - CIBFar - Center for Innovation in Biodiversity and Drug Discovery
• Grantee: Glaucius Oliva
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC