No abstract

The main stress proteins of Escherichia coli function in an ordered protein-folding reaction. DnaK (heat-shock protein 70) recognizes the folding polypeptide as an extended chain and cooperates with DnaJ in stabilizing an intermediate conformational state lacking ordered tertiary structure. Dependent on GrpE and ATP hydrolysis, the protein is then transferred to GroEL (heat-shock protein 60) which acts catalytically in the production of the native state. This sequential mechanism of chaperone action may represent an important pathway for the folding of newly synthesized polypeptides.

OPA1 processing by YEM1L and OMA1 is dispensable for mitochondrial fusion and instead drives mitochondrial fragmentation, which is crucial for mitochondrial integrity and quality control.