Diurnal oscillations of soybean circadian clock and drought responsive genes.
Rhythms produced by the endogenous circadian clock play a critical role in allowing plants to respond and adapt to the environment. While there is a well-established regulatory link between the circadian clock and responses to abiotic stress in model plants, little is known of the circadian system in crop species like soybean. This study examines how drought impacts diurnal oscillation of both drought responsive and circadian clock genes in soybean. Drought stress induced marked changes in gene expression of several circadian clock-like components, such as LCL1-, GmELF4- and PRR-like genes, which had reduced expression in stressed plants. The same conditions produced a phase advance of expression for the GmTOC1-like, GmLUX-like and GmPRR7-like genes. Similarly, the rhythmic expression pattern of the soybean drought-responsive genes DREB-, bZIP-, GOLS-, RAB18- and Remorin-like changed significantly after plant exposure to drought. In silico analysis of promoter regions of these genes revealed the presence of cis-elements associated both with stress and circadian clock regulation. Furthermore, some soybean genes with upstream ABRE elements were responsive to abscisic acid treatment. Our results indicate that some connection between the drought response and the circadian clock may exist in soybean since (i) drought stress affects gene expression of circadian clock components and (ii) several stress responsive genes display diurnal oscillation in soybeans.
Embrapa Soybean, Brazilian Agricultural Research Corporation, Londrina, Paraná, Brazil ; Department of Biology, State University of Londrina, Londrina, Paraná, Brazil.
Juliana
J
Marcolino-Gomes
Embrapa Soybean, Brazilian Agricultural Research Corporation, Londrina, Paraná, Brazil.
Fabiana Aparecida
FA
Rodrigues
Embrapa Soybean, Brazilian Agricultural Research Corporation, Londrina, Paraná, Brazil.
Renata
R
Fuganti-Pagliarini
Plant Gene Expression Center, ARS/USDA, Albany, California, USA and Department of Plant and Microbial Biology, University of California-Berkeley, Berkeley, California, USA.
Claire
C
Bendix
Department of Crop Science, Federal University of Viçosa, Viçosa, Minas Gerais, Brazil.
Thiago Jonas
TJ
Nakayama
Plant Gene Expression Center, ARS/USDA, Albany, California, USA and Department of Plant and Microbial Biology, University of California-Berkeley, Berkeley, California, USA.
Brandon
B
Celaya
Embrapa LABEX US Plant Biotechnology, Plant Gene Expression Center-ARS/USDA, Albany, California, United States of America.
Hugo Bruno Correa
HB
Molinari
Embrapa Soybean, Brazilian Agricultural Research Corporation, Londrina, Paraná, Brazil.
Maria Cristina Neves
MC
de Oliveira
Plant Gene Expression Center, ARS/USDA, Albany, California, USA and Department of Plant and Microbial Biology, University of California-Berkeley, Berkeley, California, USA.
Frank G
FG
Harmon
Embrapa Soybean, Brazilian Agricultural Research Corporation, Londrina, Paraná, Brazil ; Embrapa LABEX US Plant Biotechnology, Plant Gene Expression Center-ARS/USDA, Albany, California, United States of America.
Alexandre
A
Nepomuceno
D000040:Abscisic Acid; D000222:Adaptation, Physiological / Q000235:genetics*; D000704:Analysis of Variance; D017360:Arabidopsis / Q000235:genetics; D057906:Circadian Clocks / Q000235:genetics*; D002940:Circadian Rhythm / Q000502:physiology*; D055864:Droughts; D018506:Gene Expression Regulation, Plant / Q000235:genetics / Q000502:physiology*; D060888:Real-Time Polymerase Chain Reaction; D017423:Sequence Analysis, RNA; D013025:Glycine max / Q000235:genetics* / Q000502:physiology*
D000040:Abscisic Acid