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Programmed translational bypassing elements in mitochondria: structure, mobility, and evolutionary origin.

Jozef Nosek1, Lubomir Tomaska2, Gertraud Burger3

  • 1Department of Biochemistry, Faculty of Natural Sciences, Comenius University, Mlynska dolina CH-1, 842 15 Bratislava, Slovakia.

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|March 22, 2015
PubMed
Summary
This summary is machine-generated.

Programmed translational bypassing allows ribosomes to skip mRNA sections. Researchers suggest hop and byp elements evolved independently, with byps adapting to mitochondrial changes.

Keywords:
DNA transposonsGC clustersbacteriophage T4bypshoming endonucleaseshop

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Area of Science:

  • Molecular Biology
  • Genetics
  • Evolutionary Biology

Background:

  • Programmed translational bypassing is a mechanism where ribosomes skip specific mRNA sequences.
  • Known examples include hop elements in bacteriophage T4 and byp elements in yeast mitochondria.
  • Byp elements are more efficient and less sequence-context dependent than hop elements.

Purpose of the Study:

  • To compare the mechanisms and evolutionary origins of hop and byp elements.
  • To investigate the independent evolution of translational bypassing elements.
  • To understand the role of mitochondrial translation machinery alterations in byp evolution.

Main Methods:

  • Comparative analysis of hop and byp element sequences and mobility.
  • Bioinformatic analysis of evolutionary relationships.
  • Hypothesis-driven research on mitochondrial translation machinery.

Main Results:

  • Hop and byp elements exhibit distinct mobility mechanisms: hop as part of a homing endonuclease cassette, byps like GC-cluster transposons.
  • Byp elements are more effective and less constrained by sequence context than hop elements.
  • Evidence suggests hop and byp elements arose independently through convergent evolution.

Conclusions:

  • Hop and byp elements evolved independently, showcasing convergent evolution in translational control.
  • Byp elements likely evolved in magnusiomycete mitochondria due to specific adaptations in the translation apparatus.
  • Further research is needed to elucidate the precise alterations in mitochondrial translation machinery driving byp evolution.