Cytochrome c: Surfing off of the mitochondrial membrane on the tops of complexes III and IV

Publication date: Available online 13 May 2019Source: Computational and Structural Biotechnology JournalAuthor(s): Gonzalo Pérez-Mejías, Alejandra Guerra-Castellano, Antonio Díaz-Quintana, Miguel A. De la Rosa, Irene Díaz-MorenoAbstractThe proper arrangement of protein components within the respiratory electron transport chain is nowadays a matter of intense debate, since altering it leads to cell aging and other related pathologies. Here, we discuss three current views—the so-called solid, fluid and plasticity models—which describe the organization of the main membrane-embedded mitochondrial protein complexes and the key elements that regulate and/or facilitate supercomplex assembly. The soluble electron carrier cytochrome c has recently emerged as an essential factor in the assembly and function of respiratory supercomplexes. In fact, a ‘restricted diffusion pathway’ mechanism for electron transfer between complexes III and IV has been proposed based on the secondary, distal binding sites for cytochrome c at its two membrane partners recently discovered. This channeling pathway facilitates the surfing of cytochrome c on both respiratory complexes, thereby tuning the efficiency of oxidative phosphorylation and diminishing the production of reactive oxygen species. The well-documented post-translational modifications of cytochrome c could further contribute to the rapid adjustment of electron flow in response to changing cellular conditions.
Source: Computational and Structural Biotechnology Journal - Category: Biotechnology Source Type: research