TY  - JOUR
A1  - Mishra, Shravan Kumar
A1  - Tripp, Joanna
A1  - Winkelhaus, Sybille
A1  - Tschiersch, Bettina
A1  - Theres, Klaus
A1  - Nover, Lutz
A1  - Scharf, Klaus-Dieter
T1  - In the complex family of heat stress transcription factors, HsfA1 has a unique role as master regulator of thermotolerance in tomato
T2  - Genes & development
N2  - We generated transgenic tomato plants with altered expression of heat stress transcription factor HsfA1. Plants with 10-fold overexpression of HsfA1 (OE plants) were characterized by a singleHsfA1 transgene cassette, whereas plants harboring a tandem inverted repeat of the cassette showed cosuppression (CS plants) by posttranscriptional silencing of the HsfA1 gene connected with formation of small interfering RNAs. Under normal growth conditions, major developmental parameters were similar for wild-type (WT), OE, and CS plants. However, CS plants and fruits were extremely sensitive to elevated temperatures, because heat stress-induced synthesis of chaperones and Hsfs was strongly reduced or lacking. Despite the complexity of the plant Hsf family with at least 17 members in tomato, HsfA1 has a unique function as master regulator for induced thermotolerance. Using transient reporter assays with mesophyll protoplasts from WT tomato, we demonstrated that plasmid-encoded HsfA1 and HsfA2 were well expressed. However, in CS protoplasts the cosuppression phenomenon was faithfully reproduced. Only transformation with HsfA2 expression plasmid led to normal expression of the transcription factor and reporter gene activation, whereas even high amounts of HsfA1 expression plasmids were silenced. Thermotolerance in CS protoplasts was restored by plasmid-borne HsfA2, resulting in expression of chaperones, thermoprotection of firefly luciferase, and assembly of heat stress granules.
KW  - Posttranscriptional gene silencing
KW  - heat stress transcription factors
KW  - chaperones
KW  - siRNA
KW  - tomato
KW  - thermotolerance
Y1  - 2002
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/45615
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-456155
SN  - 1549-5477
SN  - 0890-9369
N1  - Articles not designated as Open Access are distributed exclusively by Cold Spring Harbor Laboratory Press for the first six months after the full-issue publication date (see Terms for complete details). After six months, they are available under a Creative Commons License (Attribution-NonCommercial 4.0 International License).
VL  - 16
IS  - 12
SP  - 1555
EP  - 1567
PB  - HighWire PressCold ; Laboratory Press
CY  - Stanford, Calif. ; Spring Harbor, NY
ER  -