Having it both ways: transcription factors that bind DNA and RNA

LA Cassiday, LJ Maher III - Nucleic acids research, 2002 - academic.oup.com
LA Cassiday, LJ Maher III
Nucleic acids research, 2002academic.oup.com
Multifunctional proteins challenge the conventional 'one protein–one function'paradigm.
Here we note apparent multifunctional proteins with nucleic acid partners, tabulating eight
examples. We then focus on eight additional cases of transcription factors that bind double‐
stranded DNA with sequence specificity, but that also appear to lead alternative lives as
RNA‐binding proteins. Exemplified by the prototypic Xenopus TFIIIA protein, and more
recently by mammalian p53, this list of transcription factors includes WT‐1, TRA‐1, bicoid …
Abstract
Multifunctional proteins challenge the conventional ‘one protein–one function’ paradigm. Here we note apparent multifunctional proteins with nucleic acid partners, tabulating eight examples. We then focus on eight additional cases of transcription factors that bind double‐stranded DNA with sequence specificity, but that also appear to lead alternative lives as RNA‐binding proteins. Exemplified by the prototypic Xenopus TFIIIA protein, and more recently by mammalian p53, this list of transcription factors includes WT‐1, TRA‐1, bicoid, the bacterial σ 70 subunit, STAT1 and TLS/FUS. The existence of transcription factors that bind both DNA and RNA provides an interesting puzzle. Little is known concerning the biological roles of these alternative protein–nucleic acid interactions, and even less is known concerning the structural basis for dual nucleic acid specificity. We discuss how these natural examples have motivated us to identify artificial RNA sequences that competitively inhibit a DNA‐binding transcription factor not known to have a natural RNA partner. The identification of such RNAs raises the possibility that RNA binding by DNA‐binding proteins is more common than currently appreciated.
Oxford University Press