Ldr Definition and 25 Threads

RdlD RNA (regulator detected in LDR-D) is a family of small non-coding RNAs which repress the protein LdrD in a type I toxin-antitoxin system. It was discovered in Escherichia coli strain K-12 in a long direct repeat (LDR) named LDR-D. This locus encodes two products: a 35 amino acid peptide toxin (ldrD) and a 60 nucleotide RNA antitoxin. The 374nt toxin mRNA has a half-life of around 30 minutes while rdlD RNA has a half-life of only 2 minutes. This is in keeping with other type I toxin-antitoxin systems.Northern blots showed that ldrD and rdlD are both transcribed and primer extension analysis showed the rdlD transcript is not translated.
Homologues exist in related Enterobacteriaceae such as Salmonella enterica and Shigella boydii. The Ldr peptide genes that have been discovered are thought to have evolved from a common ancestor.

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  2. D

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  3. R

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  4. T

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  5. RaulTheUCSCSlug

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  6. C

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  7. C

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  8. bradzyc

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  9. W

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  10. G

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  11. A

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  12. C

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  13. K

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  14. M

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  15. R

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  16. P

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  17. C

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  18. B

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  19. E

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  20. A

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  21. D

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  22. C

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  23. C

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  24. F

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  25. C

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