PlantTFDB
Plant Transcription Factor Database
v4.0
Previous version: v1.0, v2.0, v3.0
Petunia axillaris
HSF Family
Species TF ID Description
Peaxi162Scf00002g02718.1HSF family protein
Peaxi162Scf00004g00431.1HSF family protein
Peaxi162Scf00010g00269.1HSF family protein
Peaxi162Scf00036g00820.1HSF family protein
Peaxi162Scf00045g00131.1HSF family protein
Peaxi162Scf00112g00814.1HSF family protein
Peaxi162Scf00130g00326.1HSF family protein
Peaxi162Scf00131g00415.1HSF family protein
Peaxi162Scf00145g00167.1HSF family protein
Peaxi162Scf00154g01021.1HSF family protein
Peaxi162Scf00170g01112.1HSF family protein
Peaxi162Scf00205g00818.1HSF family protein
Peaxi162Scf00205g00820.1HSF family protein
Peaxi162Scf00221g00015.1HSF family protein
Peaxi162Scf00252g00226.1HSF family protein
Peaxi162Scf00259g00710.1HSF family protein
Peaxi162Scf00316g00518.1HSF family protein
Peaxi162Scf00327g00413.1HSF family protein
Peaxi162Scf00433g00411.1HSF family protein
Peaxi162Scf00450g00422.1HSF family protein
Peaxi162Scf00461g00026.1HSF family protein
Peaxi162Scf00498g00438.1HSF family protein
Peaxi162Scf00503g00003.1HSF family protein
Peaxi162Scf00516g00645.1HSF family protein
Peaxi162Scf00546g00118.1HSF family protein
Peaxi162Scf00560g00011.1HSF family protein
Peaxi162Scf00619g00912.1HSF family protein
Peaxi162Scf00714g00331.1HSF family protein
Peaxi162Scf00815g00357.1HSF family protein
Peaxi162Scf00915g00029.1HSF family protein
Peaxi162Scf01009g00222.1HSF family protein
Peaxi162Scf16358g00003.1HSF family protein
HSF Family Introduction

Heat stress transcription factors (Hsfs) are the major regulators of the plant heat stress (hs) response. Sequencing of the Arabidopsis genome revealed the existence of 21 open-reading frames (ORFs) encoding putative Hsfs assigned to classes A-C. Here we present results of a functional genomics approach to the Arabidopsis Hsf family focused on the analysis of their C-terminal domains (CTDs) harboring conserved modules for their function as transcription factors and their intracellular localization. Using reporter assays in tobacco protoplasts and yeast as well as glutathione-S-transferase (GST) pull-down assays, we demonstrate that short peptide motifs enriched with aromatic and large hydrophobic amino acid (aa) residues embedded in an acidic surrounding (AHA motifs) are essential for transcriptional activity of class A Hsfs. In contrast to this, class B and C Hsfs lack AHA motifs and have no activator function on their own. We also provide evidence for the function of a leucine (Leu)-rich region centered around a conserved QMGΦL motif at the very C-terminus as a nuclear export signal (NES) of class A Hsfs. Sequence comparison indicates that the combination of a C-terminal AHA motif with the consensus sequence FWxxF/L,F/I/L as well as the adjacent NES represents a signature domain for plant class A Hsfs, which allowed to identify more than 60 new Hsfs from the expressed sequence tag (EST) database.

Kotak S, Port M, Ganguli A, Bicker F, von Koskull-Doring P.
Characterization of C-terminal domains of Arabidopsis heat stress transcription factors (Hsfs) and identification of a new signature combination of plant class A Hsfs with AHA and NES motifs essential for activator function and intracellular localization.
Plant J, 2004. 39(1): p. 98-112.
PMID: 15200645