A DRP-like pseudoenzyme coordinates with MICOS to promote cristae architecture

Area of Science:

• Mitochondrial biology and function
• Cellular ultrastructure and dynamics

Background:

• Mitochondrial cristae architecture is vital for efficient cellular respiration.
• The MICOS complex is known to maintain cristae morphology, but its precise function and interactions are not fully understood.

Approach:

• Investigated the MICOS complex in the model organism *Schizosaccharomyces pombe*.
• Employed unbiased proteomics to identify novel interacting proteins.
• Characterized the function and properties of the identified protein, Mmc1.

Key Points:

• Identified Mmc1, a novel inner mitochondrial membrane protein interacting with MICOS, essential for cristae morphology.
• Mmc1 functions with MICOS to ensure normal mitochondrial morphology and respiratory efficiency.
• Mmc1, a pseudoenzyme related to Dynamin-Related Proteins, stabilizes cristae architecture as a scaffold, rather than dynamically remodeling membranes.

Conclusions:

• Mmc1 represents a new class of evolutionarily conserved proteins crucial for maintaining mitochondrial cristae architecture.
• The findings suggest a conserved mechanism involving Mmc1 and MICOS for cristae organization across different species.