title: TRF2 and the evolution of the bilateria.
abstract: The development of a complex body plan requires a diversity of regulatory networks. Here we consider the concept of TATA-box-binding protein (TBP) family proteins as "system factors" that each supports a distinct set of transcriptional programs. For instance, TBP activates TATA-box-dependent core promoters, whereas TBP-related factor 2 (TRF2) activates TATA-less core promoters that are dependent on a TCT or downstream core promoter element (DPE) motif. These findings led us to investigate the evolution of TRF2. TBP occurs in Archaea and eukaryotes, but TRF2 evolved prior to the emergence of the bilateria and subsequent to the evolutionary split between bilaterians and nonbilaterian animals. Unlike TBP, TRF2 does not bind to the TATA box and could thus function as a new system factor that is largely independent of TBP. We postulate that this TRF2-based system served as the foundation for new transcriptional programs, such as those involved in triploblasty and body plan development, that facilitated the evolution of bilateria.
authors.affiliation: Section of Molecular Biology, University of California at San Diego, La Jolla, California 92093, USA;
authors.forename: Sascha H C
authors.initials: SH
authors.lastname: Duttke
authors.affiliation: Section of Molecular Biology, University of California at San Diego, La Jolla, California 92093, USA; Department of Chemistry and Biochemistry, University of California at San Diego, La Jolla, California 92093, USA.
authors.forename: Russell F
authors.initials: RF
authors.lastname: Doolittle
authors.affiliation: Section of Molecular Biology, University of California at San Diego, La Jolla, California 92093, USA;
authors.forename: Yuan-Liang
authors.initials: YL
authors.lastname: Wang
authors.affiliation: Section of Molecular Biology, University of California at San Diego, La Jolla, California 92093, USA; jkadonaga@ucsd.edu.
authors.forename: James T
authors.initials: JT
authors.lastname: Kadonaga
mesh_terms: D000818:Animals; D005075:Biological Evolution; D019521:Body Patterning / Q000235:genetics*; D006801:Humans; D010802:Phylogeny; D011401:Promoter Regions, Genetic / Q000235:genetics; D035381:TATA-Binding Protein Associated Factors / Q000235:genetics* / Q000378:metabolism*; D014158:Transcription, Genetic / Q000235:genetics*
chemical_list: D035381:TATA-Binding Protein Associated Factors
keywords: RNA polymerase II; TBP; TRF2; bilateria; evolution; regulatory systems