Diurnal Oscillations of Soybean Circadian Clock and Drought Responsive Genes

Abstract

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.

Field‐grown soybean transcriptome shows diurnal patterns in photosynthesis‐related processes

“…Transcription of GmLCL1 and GmLCL2 declined over the course of the day, and both of these genes were assigned to cluster 4 (Figure ). The transcription patterns of these genes match the patterns measured for chamber‐grown soybean (Liu et al., ; Marcolino‐Gomes et al., ).…”

“…Expression of several other circadian‐regulated genes has been studied in chamber‐grown soybean (Marcolino‐Gomes et al., ). Therefore, we aimed to compare these previous findings to expression patterns from field‐grown soybean.…”

Differential Expression of Two-Component System–Related Drought-Responsive Genes in Two Contrasting Drought-Tolerant Soybean Cultivars DT51 and MTD720 Under Well-Watered and Drought Conditions

“…Being very sensitive to drought, soybean productivity may be lost up to 40 % in years that suffer severe drought (Thao and Tran 2012). To improve drought tolerance of soybean cultivars, many studies have been carried out to identify useful genes, including TCS-related genes that might be employed in genetic engineering (Mochida et al 2010;Le et al 2011;Marcolino-Gomes et al 2014). Previous studies revealed that soybean genome contains at least 21 HKs, 13 HP and HP-like proteins, and 46 RRs/PRRs (Mochida et al 2010;Schmutz et al 2010).…”

Circadian Clock Genes Universally Control Key Agricultural Traits

“…The clock controls a similar proportion of the transcriptome in rice, papaya, maize, soybean, and poplar (Zdepski et al, 2008;Hayes et al, 2010;Hoffman et al, 2010;Khan et al, 2010;Filichkin et al, 2011;Marcolino-Gomes et al, 2014). Genes subject to circadian clock regulation are central to many important physiological processes (Figure 1), including flowering time (Park et al, 1999;Yu et al, 2008), phytohormone synthesis and signaling Covington et al, 2008;Goodspeed et al, 2012), growth control (Nozue et al, 2007), metabolic activities (Gutierrez et al, 2008;Ni et al, 2009), abiotic stress responses (Legnaioli et al, 2009), and plant-pathogen interactions (Wang et al, 2011b).…”