Characterization and functional analysis of Arabidopsis TFIIA reveal that the evolutionarily unconserved region of the large subunit has a transcription activation domain.
TFIIA has initially been identified as a component of transcription initiation complex of RNA polymerase II. Its role in transcription has been controversial. In this paper, we report the characterization and functional analysis of both the Arabidopsis TFIIA large and small subunits. Sequence analysis revealed that Arabidopsis TFIIA is structurally more related to animal than to yeast counterparts. Arabidopsis has at least two genes for the large subunit and one for the small subunit. Both types of genes are constitutively transcribed in various plant organs. The proteins encoded by the cDNA interact each other in yeast 2-hybrid system. Only the N-terminal part of the large subunit is necessary for the interaction with the small subunit. Recombinant Arabidopsis TFIIA polypeptides bind to TBP-DNA complex in gel shift assays. The large subunit of TFIIA can stimulate transcription in yeast and in plant cells when fused to a DNA-binding domain binding to cis sequences upstream of a minimal promoter. This trans-activating activity is localized to a 35 amino acid segment within the evolutionarily unconserved central region.
Li
Y F
YF
Laboratoire de Génétique Moléculaire des Plantes, Université de Picardie Jules Verne, Amiens, France.
Le Gourierrec
J
J
Torki
M
M
Kim
Y J
YJ
Guerineau
F
F
Zhou
D X
DX
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000737:chemistry / Q000235:genetics*; D001665:Binding Sites; D017124:Conserved Sequence; D018076:DNA, Complementary / Q000235:genetics; D018744:DNA, Plant / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D019143:Evolution, Molecular; D017343:Genes, Plant / Q000235:genetics; D018745:Genome, Plant; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D035181:TATA-Box Binding Protein; D035561:Transcription Factor TFIIA; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D015533:Transcriptional Activation
D018076:DNA, Complementary; D018744:DNA, Plant; D004268:DNA-Binding Proteins; D010940:Plant Proteins; D011993:Recombinant Fusion Proteins; D035181:TATA-Box Binding Protein; D035561:Transcription Factor TFIIA; D014157:Transcription Factors