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Prokaryotes Evolve CRISPR Immune Memories with Cas9

9/5/2025

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Summary

Story summary

Prokaryotes utilize CRISPR systems to develop immune memories by integrating foreign DNA fragments.
Cas9 is essential for selecting DNA spacers and improving acquisition efficiency.
It monitors crRNA levels and controls spacer acquisition to avoid autoimmunity.
This feedback mechanism is evolutionarily conserved among different Cas9 orthologs.

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Story summary

Prokaryotes utilize CRISPR systems to develop immune memories by integrating foreign DNA fragments.
Cas9 is essential for selecting DNA spacers and improving acquisition efficiency.
It monitors crRNA levels and controls spacer acquisition to avoid autoimmunity.
This feedback mechanism is evolutionarily conserved among different Cas9 orthologs.