bims-tricox 2024-02-25 papers

Issue of 2024–02–25
three papers selected by
Yash Verma, University of Zurich

Cell Rep. 2024 Feb 21. pii: S2211-1247(24)00100-1. [Epub ahead of print]43(3): 113772

Identification of MIMAS, a multifunctional mega-assembly integrating metabolic and respiratory biogenesis factors of mitochondria.

Patrick Horten, Kuo Song, Joshua Garlich, Robert Hardt, Lilia Colina-Tenorio, Susanne E Horvath, Uwe Schulte, Bernd Fakler, Martin van der Laan, Thomas Becker, Rosemary A Stuart, Nikolaus Pfanner, Heike Rampelt.

The mitochondrial inner membrane plays central roles in bioenergetics and metabolism and contains several established membrane protein complexes. Here, we report the identification of a mega-complex of the inner membrane, termed mitochondrial multifunctional assembly (MIMAS). Its large size of 3 MDa explains why MIMAS has escaped detection in the analysis of mitochondria so far. MIMAS combines proteins of diverse functions from respiratory chain assembly to metabolite transport, dehydrogenases, and lipid biosynthesis but not the large established supercomplexes of the respiratory chain, ATP synthase, or prohibitin scaffold. MIMAS integrity depends on the non-bilayer phospholipid phosphatidylethanolamine, in contrast to respiratory supercomplexes whose stability depends on cardiolipin. Our findings suggest that MIMAS forms a protein-lipid mega-assembly in the mitochondrial inner membrane that integrates respiratory biogenesis and metabolic processes in a multifunctional platform.

Keywords: CP: Metabolism; CP: Molecular biology; membrane protein complex; metabolism; metabolite carriers; mitochondria; phosphatidylethanolamine; phospholipids; protein assembly; respiratory chain

DOI: https://doi.org/10.1016/j.celrep.2024.113772

Cell Rep. 2024 Feb 21. pii: S2211-1247(24)00202-X. [Epub ahead of print]43(3): 113874

MIMAS is a new giant multifunctional player in the mitochondrial megacomplex playground.

Kostas Tokatlidis.

Mitochondria are rich in multi-protein assemblies that are usually dedicated to one function. In this issue of Cell Reports, Horten et al.1 describe a 3-nanometer megacomplex in the mitochondrial inner membrane, which serves multiple functions integrating mitochondria biogenesis and metabolism.

DOI: https://doi.org/10.1016/j.celrep.2024.113874

J Genet. 2024 ;pii: 09. [Epub ahead of print]103

Efficient assembly of a synthetic attenuated SARS-CoV-2 genome in Saccharomyces cerevisiae using multi-copy yeast vectors.

Abhishek Kumar Singh, Harsh Goar, Nikita Vashist, Prakash Sinha, Anand Kumar Bachhawat.

Saccharomyces cerevisiae has been demonstrated to be an excellent platform for the multi-fragment assembly of large DNA constructs through its powerful homologous recombination ability. These assemblies have invariably used the stable centromeric single copy vectors. However, many applications of these assembled genomes would benefit from assembly in a higher copy number vector for improved downstream extraction of intact genomes from the yeast. A review of the literature revealed that large multi-fragment assemblies did not appear to have been attempted in multicopy vectors. Therefore, we devised a toolkit that would enable one to seamlessly transition with the same assembling fragments between a single copy and a multicopy vector. We evaluated the assembly of a 28 kb attenuated SARSCoV- 2 genome (lacking the N gene) from 10 fragments in both single copy and multicopy vector systems. Our results reveal that assembly was comparably efficient in the two vector systems. The findings should add to the synthetic biology toolkit of S. cerevisiae and should enable researchers to utilize any of these vector systems depending on their downstream applications.