Details

Autor(en) / Beteiligte

• Li, Zhaoxia
• Tang, Jie
• Srivastava, Renu
• Bassham, Diane C
• Howell, Stephen H

Titel

The Transcription Factor bZIP60 Links the Unfolded Protein Response to the Heat Stress Response in Maize

Ist Teil von

• The Plant cell, 2020-11, Vol.32 (11), p.3559-3575

Ort / Verlag

England: American Society of Plant Biologists

Erscheinungsjahr

2020

Quelle

MEDLINE

Beschreibungen/Notizen

• The unfolded protein response (UPR) and the heat shock response (HSR) are two evolutionarily conserved systems that protect plants from heat stress. The UPR and HSR occur in different cellular compartments and both responses are elicited by misfolded proteins that accumulate under adverse environmental conditions such as heat stress. While the UPR and HSR appear to operate independently, we have found a link between them in maize ( ) involving the production of the BASIC LEUCINE ZIPPER60 (bZIP60) transcription factor, a pivotal response of the UPR to heat stress. Surprisingly, a mutant ( - ) knocking down expression blunted the HSR at elevated temperatures and prevented the normal upregulation of a group of heat shock protein genes in response to elevated temperature. The expression of a key ( , a [ ] family member) was compromised in - , and the promoter was shown to be a target of bZIP60 in maize protoplasts. In addition, the upregulation by heat of genes involved in chlorophyll catabolism and chloroplast protein turnover were subdued in - , and these genes were also found to be targets of bZIP60. Thus, the UPR, an endoplasmic-reticulum-associated response, quite unexpectedly contributes to the nuclear/cytoplasmic HSR in maize.