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This content will become publicly available on September 22, 2024

Title: Short tandem repeats bind transcription factors to tune eukaryotic gene expression
Short tandem repeats (STRs) are enriched in eukaryoticcis-regulatory elements and alter gene expression, yet how they regulate transcription remains unknown. We found that STRs modulate transcription factor (TF)–DNA affinities and apparent on-rates by about 70-fold by directly binding TF DNA-binding domains, with energetic impacts exceeding many consensus motif mutations. STRs maximize the number of weakly preferred microstates near target sites, thereby increasing TF density, with impacts well predicted by statistical mechanics. Confirming that STRs also affect TF binding in cells, neural networks trained only on in vivo occupancies predicted effects identical to those observed in vitro. Approximately 90% of TFs preferentially bound STRs that need not resemble known motifs, providing a cis-regulatory mechanism to target TFs to genomic sites.  more » « less
Award ID(s):
2142336
NSF-PAR ID:
10478516
Author(s) / Creator(s):
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Publisher / Repository:
AAAS
Date Published:
Journal Name:
Science
Volume:
381
Issue:
6664
ISSN:
0036-8075
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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