Arabidopsis AtSUC2 and AtSUC4, encoding sucrose transporters, are required for abiotic stress tolerance in an ABA‐dependent pathway

Abstract

Sucrose transporters (SUCs or SUTs) play a central role, as they orchestrate sucrose allocation both intracellularly and at the whole plant level. Previously, we found AtSUC4 mutants changing sucrose distribution under drought and salt stresses. Here, we systematically examined the role of Arabidopsis AtSUC2 and AtSUC4 in response to abiotic stress. The results showed significant induction of AtSUC2 and AtSUC4 in salt, osmotic, low temperature and exogenous abscisic acid (ABA) treatments by public microarray data and real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) analyses. The loss-of-function mutation of AtSUC2 and AtSUC4 led to hypersensitive responses to abiotic stress and ABA treatment in seed germination and seedling growth. These mutants also showed higher sucrose content in shoots and lower sucrose content in roots, as compared with that in wild-type plants, and inhibited the ABA-induced expression of many stress- and ABA-responsive genes, especially ABFs and ABF-downstream and upstream genes. The loss-of-function mutant of AtSUC3, a unique putative sucrose sensor, reduced the expression of AtSUC2 and AtSUC4 in response to abiotic stresses and ABA. These findings confirmed that AtSUC2 and AtSUC4 are important regulators in plant abiotic stress tolerance that use an ABA signaling pathway, which may be crossed with sucrose signaling.

Water Deficit Enhances C Export to the Roots in Arabidopsis thaliana Plants with Contribution of Sucrose Transporters in Both Shoot and Roots

“…Several other results provide evidence that leaf Suc transporter gene expression is tuned by water deficit (Fig. 10), as in grapevine (Medici et al, 2014), rice (Oryza sativa; Ibraheem et al, 2011), and Arabidopsis (Gong et al, 2015). As source strength is defined as the ability to export sugar to sinks, our data demonstrate that the leaves of WD plants were a stronger source when the data were weighted by leaf mass.…”

Effects of cold acclimation on sugar metabolism and sugar-related gene expression in tea plant during the winter season

“…In silico analyses of the promoter regions of SUTs in Arabidopsis and rice showed that these regions contained LT response elements and other stress response elements, indicating that SUT might be regulated by cold temperatures (Ibraheem et al 2010). Recently, Gong et al (2015) reported that AtSUC2 and AtSUC4 were induced by cold and loss-of-function mutations resulted in hypersensitive responses to abiotic stress. Additionally, most cold-induced transporters are positively correlated with plant cold tolerance via the modulation of sugar allocation, such as MfINT-like (Sambe et al 2015), BvIMP (ERD6-like) (Klemens et al 2013b) and AtTMTs (Schulze et al 2012;Wormit et al 2006), suggesting that the up-regulated genes in the tea plant could exhibit similar functions as their homologous genes.…”

Comparison on the carbohydrate metabolic enzyme activities and their gene expression patterns in canola differing seed oil content

“…Because sucrose metabolism is distributed universally, wide association of sucrose transporter with other traits is predicted Gong et al 2015). For example, Li et al (2011) identified sucrose transporter alleles in Brassica napus that significantly correlated with seed yield traits, including number of effective branches, siliques per plant, and seed weight.…”