The guide-RNA sequence dictates the slicing kinetics and conformational dynamics of the Argonaute silencing complex.
Mol Cell
; 84(15): 2918-2934.e11, 2024 Aug 08.
Article
in En
| MEDLINE
| ID: mdl-39025072
ABSTRACT
The RNA-induced silencing complex (RISC), which powers RNA interference (RNAi), consists of a guide RNA and an Argonaute protein that slices target RNAs complementary to the guide. We find that, for different guide-RNA sequences, slicing rates of perfectly complementary bound targets can be surprisingly different (>250-fold range), and that faster slicing confers better knockdown in cells. Nucleotide sequence identities at guide-RNA positions 7, 10, and 17 underlie much of this variation in slicing rates. Analysis of one of these determinants implicates a structural distortion at guide nucleotides 6-7 in promoting slicing. Moreover, slicing directed by different guide sequences has an unanticipated, 600-fold range in 3'-mismatch tolerance, attributable to guides with weak (AU-rich) central pairing requiring extensive 3' complementarity (pairing beyond position 16) to more fully populate the slicing-competent conformation. Together, our analyses identify sequence determinants of RISC activity and provide biochemical and conformational rationale for their action.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
RNA-Induced Silencing Complex
/
Argonaute Proteins
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RNA, Guide, CRISPR-Cas Systems
/
Nucleic Acid Conformation
Limits:
Humans
Language:
En
Journal:
Mol Cell
Journal subject:
BIOLOGIA MOLECULAR
Year:
2024
Document type:
Article
Affiliation country:
Country of publication: