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Title: A suboptimal OCT4-SOX2 binding site facilitates the naïve-state specific function of a Klf4 enhancer
Enhancers have critical functions in the precise, spatiotemporal control of transcription during development. It is thought that enhancer grammar, or the characteristics and arrangements of transcription factor binding sites, underlie the specific functions of developmental enhancers. In this study, we sought to identify grammatical constraints that direct enhancer activity in the naïve state of pluripotency, focusing on the enhancers for the naïve-state specific gene,Klf4. Using a combination of biochemical tests, reporter assays, and endogenous mutations in mouse embryonic stem cells, we have studied the binding sites for the transcription factors OCT4 and SOX2. We have found that the threeKlf4enhancers contain suboptimal OCT4-SOX2 composite binding sites. Substitution with a high-affinity OCT4-SOX2 binding site inKlf4enhancer E2 rescued enhancer function andKlf4expression upon loss of the ESRRB and STAT3 binding sites. We also observed that the low-affinity of the OCT4-SOX2 binding site is crucial to drive the naïve-state specific activities ofKlf4enhancer E2. Altogether, our work suggests that the affinity of OCT4-SOX2 binding sites could facilitate enhancer functions in specific states of pluripotency.  more » « less
Award ID(s):
2117304 2335201
PAR ID:
10553168
Author(s) / Creator(s):
; ; ; ; ;
Editor(s):
Vall-llosera_Camps, Miquel
Publisher / Repository:
PLoS ONE
Date Published:
Journal Name:
PLOS ONE
Volume:
19
Issue:
9
ISSN:
1932-6203
Page Range / eLocation ID:
e0311120
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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