OsCIPK31, a CBL-Interacting Protein Kinase Is Involved in Germination and Seedling Growth under Abiotic Stress Conditions in Rice Plants

Abstract

Calcineurin B-like protein-interacting protein kinases (CIPKs) are a group of typical Ser/Thr protein kinases that mediate calcium signals. Extensive studies using Arabidopsis plants have demonstrated that many calcium signatures that activate CIPKs originate from abiotic stresses. However, there are few reports on the functional demonstration of CIPKs in other plants, especially in grasses. In this study, we used a loss-of-function mutation to characterize the function of the rice CIPK gene OsCIPK31. Exposure to high concentrations of NaCl or mannitol effected a rapid and transient enhancement of OsCIPK31 expression. These findings were observed only in the light. However, longer exposure to most stresses resulted in downregulation of OsCIPK31 expression in both the presence and absence of light. To determine the physiological roles of OsCIPK31 in rice plants, the sensitivity of oscipk31::Ds, which is a transposon Ds insertion mutant, to abiotic stresses was examined during germination and seedling stages. oscipk31::Ds mutants exhibited hypersensitive phenotypes to ABA, salt, mannitol, and glucose. Compared with wild-type rice plants, mutants exhibited retarded germination and slow seedling growth. In addition, oscipk31::Ds seedlings exhibited enhanced expression of several stress-responsive genes after exposure to these abiotic stresses. However, the expression of ABA metabolic genes and the endogenous levels of ABA were not altered significantly in the oscipk31::Ds mutant. This study demonstrated that rice plants use OsCIPK31 to modulate responses to abiotic stresses during the seed germination and seedling stages and to modulate the expression of stress-responsive genes.

Calcium and Reactive Oxygen Species Rule the Waves of Signaling

“…Moreover, lately, five novel CIPKs and two CBLs have been discovered in kidney bean (Phaseolus vulgaris) and 43 putative CIPK genes that are closely related to rice CIPKs have been identified in maize (Zea mays; Hamada et al, 2009;Chen et al, 2011). A function of a rice CIPK has been reported for OsCIPK31, which was found to modulate responses to abiotic stresses during seed germination and seedling growth (Piao et al, 2010), and OsCIPK23, which turned out to be a multistress-induced gene likely regulating signaling pathways during pollination and drought stress responses (Yang et al, 2008). Another example for a multifunctional rice CIPK is OsCIPK15, which has been implicated in mediating oxygen deficiency tolerance as well as being involved in various PAMPinduced immune responses together with OsCIPK14 (Lee et al, 2009a;Kurusu et al, 2010).…”

“…The diverse spectrum of plants in which CBL and CIPK function was analyzed encompasses species such as rice, rape (Brassica napus), wheat (Triticum aestivum), sorghum (Sorghum bicolor), apple (Malus domestica), cotton (Gossypium hirsutum), and poplar (Populus spp. ; Yang et al, 2008;Piao et al, 2010;Zhang et al, 2011Zhang et al, , 2013Chen et al, 2012;Wang et al, 2012;Deng et al, 2013;He et al, 2013). Moreover, lately, five novel CIPKs and two CBLs have been discovered in kidney bean (Phaseolus vulgaris) and 43 putative CIPK genes that are closely related to rice CIPKs have been identified in maize (Zea mays; Hamada et al, 2009;Chen et al, 2011).…”

Decrypting Calcium Signaling in Plants: The Kinase Way

“…Conservation of the SOS pathway has been reported in rice, Brassica juncea , maize, tomato, Populus trichocarpa , Populus euphratica , and apple (Martínez-Atienza et al 2007 ;Wang et al 2007Wang et al , 2012aKumar et al 2009 ;Zhao et al 2009 ;Kushwaha et al 2011 ;Hu et al 2012 ;Tang et al 2010 ;Lv et al 2014 ;Oh et al 2008 ). From monocots like rice and wheat, using reverse functional genetic tool such as gain/loss of function of OsCIPK3, OsCIPK12, OsCIPK15, OsCIPK23, OsCIPK31, and TaCIPK14 has been demonstrated to be intricately involved in diverse abiotic stress pathways, namely, cold, salt, PEG, ABA, ethylene, and H 2 O 2 (Xiang et al 2007 ;Yang et al 2008 ;Piao et al 2010 ;Deng et al 2013a ). With more studies being reported from multiple plant species, the nitty-gritty of Ca 2+ signaling network and role of CDPK and CBL-CIPK proteins will be further elucidated.…”

Functional Role of CBL–CIPK in Plant Development

“…Besides this, CIPK14 appeared to be regulated by both the circadian clock and PhyA, and involved in phytochrome A-mediated far-red light inhibition of greening in Arabidopsis seedlings [6]. In rice, OsCIPK31 has been identified to modulate responses to abiotic stresses during seed germination and seedling growth [5].…”