OsRACK1A, encodes a circadian clock-regulated WD40 protein, negatively affect salt tolerance in rice

• Published in: Rice (New York, N.Y.) Vol. 11; no. 1; pp. 45 - 15
• Main Authors: Zhang, Dongping, Wang, Yuzhu, Shen, Jinyu, Yin, Jianfeng, Li, Dahong, Gao, Yan, Xu, Weifeng, Liang, Jiansheng
• Format: Journal Article
• Language: English
• Published: New York Springer US 02-08-2018; Springer Nature B.V; SpringerOpen
• Subjects: Abiotic stress; Abscisic acid; Agriculture; Biological clocks; Biomedical and Life Sciences; Chlorophyll; Circadian; Circadian rhythm; Circadian rhythms; Eukaryotes; Genes; Ion concentration; Kinases; Life Sciences; Malondialdehyde; Original; Original Article; Oryza; OsRACK1A; Plant Breeding/Biotechnology; Plant Ecology; Plant Genetics and Genomics; Plant Sciences; Polymerase chain reaction; Prokaryotes; Proline; Proteins; Rice; Salt; Salt tolerance; Stress concentration; Survival; Transcription factors; OsRACK1A; Salt tolerance; Circadian; Rice
• ISSN: 1939-8425; 1939-8433; 1934-8037
• DOI: 10.1186/s12284-018-0232-3

The receptor for activated C kinase 1 (RACK1) is a WD40 type protein that is involved in multiple signaling pathways and is conserved from prokaryotes to eukaryotes. Here we report that rice
RACK1A
(
OsRACK1A
) is regulated by circadian clocks and plays an important role in the salt stress response.
OsRACK1A
was found to follow a rhythmic expression profile under circadian conditions at both the transcription and the translation levels, although the expression was arrhythmic under salt stress. Analysis of plant survival rates, fresh weight, proline content, malondialdehyde, and chlorophyll showed that suppression of
OsRACK1A
enhanced tolerance to salt stress. The ion concentration in both roots and leaves revealed that
OsRACK1A
-suppressed transgenic rice could maintain low Na
+
and high K
+
concentrations. Furthermore,
OsRACK1A
-suppressed transgenic rice accumulated significantly more abscisic acid (ABA) and more transcripts of ABA- and stress-inducible genes compared with the wild-type plants. Real-time quantitative polymerase chain reaction analysis revealed that many stress-related genes, including APETALA 2/Ethylene Responsive Factor (AP2/ERF) transcription factors, were upregulated in the
OsRACK1A
-suppressed transgenic rice line. We identified putative interactors of OsRACK1A, and found that OsRACK1A interacted with many salt stress-responsive proteins directly. These results suggest that
OsRACK1A
is regulated by circadian rhythm, and involved in the regulation of salt stress responses.