Rcf proteins and their differential specificity for respiratory chain complexes: A unique role for Rcf2 on oxygen sensitive supercomplexes?
Details
Publication Year 2021-08-25,Volume 1868,Issue #12,Page 119133
Journal Title
Biochimica et Biophysica acta. Molecular Cell Research
Abstract
The respiratory chain, embedded in the inner mitochondrial membrane, is organized as a network of individual complexes, as well as large supercomplex structures. In the yeast S. cerevisiae, these supercomplexes consist of a dimeric cytochrome bc1-complex adjoined by one or two copies of cytochrome c oxidase. The formation of these complexes is a dynamic process and is regulated by various factors in order to adapt to environmental and metabolic changes. These adaptions occur at the level of enzyme regulation, complex assembly, as well as altered nuclear and mitochondrial transcription and translation. Members of the Rcf protein family (Rcf1, Rcf2 and Rcf3) are required for respiratory complex biogenesis and act mainly by regulating the assembly and enzyme activity of complex IV within supercomplexes. Rcf1 functions in the assembly process via the COX3 module, whereas Rcf2 and Rcf3 are responsible for enzymatic regulation. In this study, we have extended this knowledge to show that Rcf2 and Rcf3 can also associate with newly synthesized mitochondrial encoded proteins, such as Cox3, and therefore contribute to complex IV assembly. Since the Rcf proteins have overlapping regions of sequence similarities, we engineered novel fusion proteins of Rcf1 and Rcf3, with parts of Rcf2, to probe which of the Rcf protein domains can be attributed to their functions. The fusion proteins could compensate for the individual phenotypes of the complexIV assembly defect and the lack of complex IV regulation. Finally, the role of Rcf proteins for defined species of respiratory chain complexes in a hypoxic model was investigated, uncovering a unique association of Rcf2 with the hypoxic III2IV supercomplex. We therefore suggest an involvement of Rcf2 for adaption of the respiratory chain to altering oxygen levels.
Publisher
Elsevier
Research Division(s)
Ubiquitin Signalling
PubMed ID
34450214
Terms of Use/Rights Notice
Refer to copyright notice on published article.


Creation Date: 2021-10-26 10:03:46
Last Modified: 2021-10-26 10:28:25
An error has occurred. This application may no longer respond until reloaded. Reload 🗙