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Mitochondrial tRNA processing: a neutral evolutionary ratchet innovation.

Lien B Lai1, Jane E Jackman1, Charles J Daniels2

  • 1Department of Chemistry & Biochemistry, The Ohio State University, Columbus, OH 43210, USA; Center for RNA Biology, The Ohio State University, Columbus, OH 43210, USA.

Trends in Biochemical Sciences
|June 28, 2025
PubMed
Summary
This summary is machine-generated.

Mitochondrial transfer RNA (tRNA) processing demonstrates molecular adaptability. A complex enzyme system rescues compromised tRNAs, showcasing biological complexity arising from nonadaptive mechanisms.

Keywords:
compensatory coevolutionconstructive neutral evolutionmitochondriatRNA maturation

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Area of Science:

  • Molecular Biology
  • Evolutionary Biology
  • Biochemistry

Background:

  • Mitochondrial transfer RNAs (tRNAs) are essential for protein synthesis.
  • Proper processing of mitochondrial tRNAs is crucial for cellular function.
  • Structural defects in mitochondrial tRNAs can impair protein synthesis.

Purpose of the Study:

  • To investigate the mechanisms behind the processing of structurally compromised mitochondrial tRNAs.
  • To explore the role of multienzyme complexes in mitochondrial tRNA maturation.
  • To understand how nonadaptive evolutionary processes can lead to biological complexity.

Main Methods:

  • Analysis of mitochondrial tRNA processing pathways.
  • Biochemical characterization of relevant enzyme complexes.
  • Evolutionary analysis of molecular mechanisms.

Main Results:

  • A multienzyme complex was identified that rescues structurally compromised mitochondrial tRNAs.
  • This complex appears to be shaped by constructive neutral evolution.
  • The processing system represents a robust, albeit precarious, innovation.

Conclusions:

  • Mitochondrial tRNA processing highlights molecular adaptability.
  • Biological complexity can arise from nonadaptive evolutionary mechanisms.
  • A potential vulnerability in mitochondrial tRNA structure is transformed into a functional innovation.