PlantTFDB
Plant Transcription Factor Database
v4.0
Previous version: v1.0, v2.0, v3.0
Pyrus bretschneideri
HSF Family
Species TF ID Description
Pbr000355.1HSF family protein
Pbr000538.1HSF family protein
Pbr002020.1HSF family protein
Pbr002038.1HSF family protein
Pbr005379.1HSF family protein
Pbr005496.1HSF family protein
Pbr007349.1HSF family protein
Pbr007777.1HSF family protein
Pbr008509.1HSF family protein
Pbr009953.1HSF family protein
Pbr012136.1HSF family protein
Pbr012846.1HSF family protein
Pbr012908.1HSF family protein
Pbr013953.1HSF family protein
Pbr014107.1HSF family protein
Pbr014670.1HSF family protein
Pbr015630.1HSF family protein
Pbr016090.1HSF family protein
Pbr016270.1HSF family protein
Pbr016487.1HSF family protein
Pbr016805.1HSF family protein
Pbr016948.1HSF family protein
Pbr018847.1HSF family protein
Pbr019653.1HSF family protein
Pbr019856.1HSF family protein
Pbr022463.1HSF family protein
Pbr025141.1HSF family protein
Pbr025227.1HSF family protein
Pbr030422.1HSF family protein
Pbr030436.1HSF family protein
Pbr031411.1HSF family protein
Pbr036788.1HSF family protein
Pbr037242.1HSF family protein
Pbr039282.1HSF family protein
Pbr040862.1HSF family protein
Pbr041026.1HSF family protein
Pbr041474.1HSF 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