Disruption of OsSULTR3;3 reduces phytate and phosphorus concentrations and alters the metabolite profile in rice grains.

Two low phytic acid (lpa) mutants have been developed previously with the aim to improve the nutritional value of rice (Oryza sativa) grains. In the present study, the impacts of lpa mutations on grain composition and underlying molecular mechanisms were investigated. Comparative compositional analyses and metabolite profiling demonstrated that concentrations of both phytic acid (PA) and total phosphorus (P) were significantly reduced in lpa brown rice, accompanied by changes in other metabolites and increased concentrations of nutritionally relevant compounds.

Spatio-temporal transcript profiling of rice roots and shoots in response to phosphate starvation and recovery.

Using rice (Oryza sativa) as a model crop species, we performed an in-depth temporal transcriptome analysis, covering the early and late stages of Pi deprivation as well as Pi recovery in roots and shoots, using next-generation sequencing. Analyses of 126 paired-end RNA sequencing libraries, spanning nine time points, provided a comprehensive overview of the dynamic responses of rice to Pi stress. Differentially expressed genes were grouped into eight sets based on their responses to Pi starvation and recovery, enabling the complex signaling pathways involved in Pi homeostasis to be untangled.

A rice cis-natural antisense RNA acts as a translational enhancer for its cognate mRNA and contributes to phosphate homeostasis and plant fitness.

cis-natural antisense transcripts (cis-NATs) are widespread in plants and are often associated with downregulation of their associated sense genes. We found that a cis-NAT positively regulates the level of a protein critical for phosphate homeostasis in rice (Oryza sativa). PHOSPHATE1;2 (PHO1;2), a gene involved in phosphate loading into the xylem in rice, and its associated cis-NATPHO1;2 are both controlled by promoters active in the vascular cylinder of roots and leaves.

Diversity in expression patterns and functional properties in the rice HKT transporter family.

Plant growth under low K(+) availability or salt stress requires tight control of K(+) and Na(+) uptake, long-distance transport, and accumulation. The family of membrane transporters named HKT (for High-Affinity K(+) Transporters), permeable either to K(+) and Na(+) or to Na(+) only, is thought to play major roles in these functions. Whereas Arabidopsis (Arabidopsis thaliana) possesses a single HKT transporter, involved in Na(+) transport in vascular tissues, a larger number of HKT transporters are present in rice (Oryza sativa) as well as in other monocots.