E-GEOD-44748 - Genome-wide binding profiles of KLF3 and KLF3 mutants in MEF cells

Status
Released on 17 October 2013, last updated on 3 May 2014
Organism
Mus musculus
Samples (6)
Protocols (3)
Description
Transcription factors are often regarded as being comprised of a DNA-binding domain and a functional domain. The two domains are considered separable and autonomous, with the DNA-binding domain directing the factor to its target genes and the functional domain imparting transcriptional regulation. We have examined a typical Zinc Finger (ZF) transcription factor from the Krüppel-like factor (KLF) family, KLF3. This factor has an N-terminal repression domain that binds the co-repressor C-terminal binding protein (CtBP), and a DNA-binding domain composed of three classical (ZFs) at its C-terminus. We established a system to compare the genomic occupancy profile of wildtype KLF3 with two mutants affecting the N-terminal functional domain: a mutant unable to contact its cofactor CtBP and a mutant lacking the entire N-terminal domain, but retaining the ZFs intact. We used chromatin immunoprecipitation followed by sequencing (ChIP-seq) to assess binding across the genome in murine embryonic fibroblasts. Our results define the in vivo recognition site for KLF3 and the two mutants as a typical CACCC-like element. Unexpectedly, we observe that mutations in the N-terminal functional domain severely affect DNA binding. In general, both mutations reduce binding but there are also instances where binding is retained or even increased. These results provide a clear demonstration that the correct localization of transcription factors to their target genes is not solely dependent on their DNA-contact domains. This informs our understanding of how transcription factors operate and is of relevance to the design of artificial ZF proteins. ChIP-seq was performed on the three samples, KLF3, ΔDL and DBD in duplicate (biological replicates). Input samples were used as controls.
Experiment type
ChIP-seq 
Contacts
Jon Burdach <geo@ncbi.nlm.nih.gov>, Alister P Funnell, Crisbel M Artuz, Lit Y Tan, Mak K Sin, Merlin Crossley, Richard C Pearson
Citation
MINSEQE
Exp. designProtocolsFactorsProcessedSeq. reads
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