Human mitochondrial peroxiredoxin Prdx3 is dually localized in the intermembrane space and matrix subcompartments

Author(s)

Gomes, Fernando ; Turano, Helena ; Haddad, Luciana A. ; Netto, Luis. E. S.

• Document type: Journal article
• Source: REDOX BIOLOGY; v. 78, p. 13-pg., 2024-11-25.

Abstract

Peroxiredoxin 3 (Prdx3) is the major sink for H2O2 and other hydroperoxides within mitochondria, yet the mechanisms guiding the import of its cytosolic precursor into mitochondrial sub-compartments remain elusive. Prdx3 is synthesized in the cytosol as a precursor with an N-terminal cleavable presequence, which is frequently proposed to target the protein exclusively to the mitochondrial matrix. Here, we present a comprehensive analysis of the human Prdx3 biogenesis, using highly purified mitochondria from HEK293T cells. Sub- fractionation and probing for specific mitochondrial markers confirmed Prdx3 localization in the matrix, while unexpectedly revealed its presence in the mitochondrial intermembrane space (IMS). Both matrix and IMS isoforms were found to be soluble proteins, as demonstrated by alkaline carbonate extraction. By combining in silico analysis, in organello import assays and heterologous expression in yeast, we found that Prdx3 undergoes sequential proteolytic processing steps by mitochondrial processing peptidase (MPP) and mitochondrial intermediate peptidase (MIP) during its import into the matrix. Additionally, heterologous expression of Prdx3 in yeast revealed that its sorting to the IMS is dependent on the inner membrane peptidase (IMP) complex. Collectively, these findings uncover a complex submitochondrial distribution of Prdx3, supporting its multifaceted role in mitochondrial H2O2 metabolism. (AU)

• FAPESP's process: 22/08446-7 - Molecular mechanisms underlying the suborganellar distribution of mammalian mitochondrial peroxiredoxins: impacts on physiology and pathology
• Grantee: Luis Eduardo Soares Netto
• Support Opportunities: Regular Research Grants
• FAPESP's process: 23/01812-0 - Dissecting the molecular mechanisms underlying the mitochondrial import of mammalian peroxiredoxin 3 (Prdx3)
• Grantee: Fernando Gomes
• Support Opportunities: Scholarships in Brazil - Technical Training Program - Technical Training
• FAPESP's process: 17/09443-3 - Importing of peroxiredoxins to distinct mitochondrial compartments: impacts on physiology and pathology
• Grantee: Fernando Gomes
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 13/07937-8 - Redoxome - Redox Processes in Biomedicine
• Grantee: Ohara Augusto
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC
• FAPESP's process: 17/23839-7 - Investigation of the S8 pyocin bactericidal activity: new perspectives for the treatment of infections caused by multidrug-resistant Pseudomonas aeruginosa strains
• Grantee: Helena Gabriela Turano Gomes
• Support Opportunities: Scholarships in Brazil - Post-Doctoral