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Updated: Jul 13, 2026
07:44
High-throughput Purification of Affinity-tagged Recombinant Proteins
Published on: August 26, 2012
A cellular DNA-binding protein that activates eukaryotic transcription and DNA replication
Cell
|January 16, 1987
Summary
Transcription factor CTF recognizes eukaryotic promoters. CTF and nuclear factor I (NF-I) are identical, acting as transcription and DNA replication factors.
Area of Science:
- Molecular Biology
- Biochemistry
- Genetics
Background:
- The CCAAT sequence in eukaryotic promoters is recognized by transcription factor CTF.
- Nuclear factor I (NF-I) is crucial for initiating adenovirus DNA replication in vitro.
- CTF and NF-I bind to homologous sequences in human gene promoters.
Purpose of the Study:
- To investigate the relationship between transcription factor CTF and nuclear factor I (NF-I).
- To compare the biochemical properties of CTF and NF-I.
Main Methods:
- Purification of transcription factor CTF using sequence-specific DNA affinity chromatography.
- Comparative analysis of polypeptide composition, DNA-binding properties, and immunological cross-reactivity between CTF and NF-I.
- In vitro assays to assess the stimulation of DNA replication and transcription initiation by CTF and NF-I.
Main Results:
- CTF was purified to homogeneity.
- CTF and NF-I exhibited indistinguishable biochemical properties.
- Both proteins showed identical polypeptide composition and DNA-binding characteristics.
- CTF/NF-I stimulated both DNA replication and transcription initiation in vitro.
Conclusions:
- Transcription factor CTF and nuclear factor I (NF-I) are the same protein.
- CTF/NF-I functions as a dual-activity factor.
- This factor is essential for selective transcription initiation by RNA polymerase II.
- It also plays a critical role in the initiation of adenovirus DNA replication.
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