PlantTFDB
Plant Transcription Factor Database
v4.0
Previous version: v1.0, v2.0, v3.0
Linum usitatissimum
HSF Family
Species TF ID Description
Lus10000312HSF family protein
Lus10000492HSF family protein
Lus10001133HSF family protein
Lus10001591HSF family protein
Lus10003707HSF family protein
Lus10005420HSF family protein
Lus10005925HSF family protein
Lus10006618HSF family protein
Lus10007318HSF family protein
Lus10008007HSF family protein
Lus10009351HSF family protein
Lus10011065HSF family protein
Lus10011185HSF family protein
Lus10011941HSF family protein
Lus10013797HSF family protein
Lus10014369HSF family protein
Lus10014698HSF family protein
Lus10014994HSF family protein
Lus10015237HSF family protein
Lus10016634HSF family protein
Lus10018488HSF family protein
Lus10019348HSF family protein
Lus10022083HSF family protein
Lus10022546HSF family protein
Lus10023636HSF family protein
Lus10023866HSF family protein
Lus10024508HSF family protein
Lus10026819HSF family protein
Lus10027627HSF family protein
Lus10029269HSF family protein
Lus10029852HSF family protein
Lus10030956HSF family protein
Lus10034907HSF family protein
Lus10036062HSF family protein
Lus10038874HSF family protein
Lus10039134HSF family protein
Lus10039376HSF family protein
Lus10040091HSF family protein
Lus10040911HSF family protein
Lus10042646HSF 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