The protein kinase Pstol1 from traditional rice confers tolerance of phosphorus deficiency Gamuyao et al., 2012. Nature 12-04-2015 1/16

Biological role Phosphorus (P) is an essential macronutrient for plant growth It is central to a majority of the molecular constituents required for the functioning of plant cells. DNA; RNA; Proteins; Lipids; Sugars, ATP, ADP, and NADPH It is indispensable in agricultural production 2/16

The problem of phosphorus Kochian Nature 488, 466–467 (2012) doi:10.1038/488466a 3/16

Origin of the donor variety Kasalath Pup1 aus-type variety Aoosh (early) This group of rice is famously known to tolerate difficult growing conditions R Gamuyao et al. Nature 488, 535-539 (2012) doi:10.1038/nature11346 4/16

R Gamuyao et al. Nature 488, 535-539 (2012) doi:10.1038/nature11346 Phosphorus uptake 1 (Pup1) candidate genes OsPupK46-2 R Gamuyao et al. Nature 488, 535-539 (2012) doi:10.1038/nature11346 5/16

R Gamuyao et al. Nature 488, 535-539 (2012) doi:10.1038/nature11346 Which one is the major determinant of P-deficiency tolerance in Kasalath? -P conditions With or without P fertilizer Nipponbare near-isogenic lines(NILs) OsPupK46-2 Phosphorus-Starvation Tolerance 1 Postl 1 is the major genetic determinant of P-deficiency tolerance R Gamuyao et al. Nature 488, 535-539 (2012) doi:10.1038/nature11346 6/16

R Gamuyao et al. Nature 488, 535-539 (2012) doi:10.1038/nature11346 How Pstol1 involved with the P-efficient ? in vitro phosphorylation assay Pstol1 is a functional protein kinase R Gamuyao et al. Nature 488, 535-539 (2012) doi:10.1038/nature11346 7/16

R Gamuyao et al. Nature 488, 535-539 (2012) doi:10.1038/nature11346 PSTOL1 overexpression enhances tolerance of P deficiency 35S::PSTOL1 Indica Japonica 8/16 R Gamuyao et al. Nature 488, 535-539 (2012) doi:10.1038/nature11346

R Gamuyao et al. Nature 488, 535-539 (2012) doi:10.1038/nature11346 The larger root system also enhanced the uptake of other nutrients R Gamuyao et al. Nature 488, 535-539 (2012) doi:10.1038/nature11346 10/16

How Pstol1 involved with the P-efficient? By enhancing root growth? 11/16

R Gamuyao et al. Nature 488, 535-539 (2012) doi:10.1038/nature11346 Really ? 10mM 100mM Pstol1 IR64 transgenics PSTOL1 is an enhancer of root growth and independent of phosphorus or soil-related conditions R Gamuyao et al. Nature 488, 535-539 (2012) doi:10.1038/nature11346 12/16

R Gamuyao et al. Nature 488, 535-539 (2012) doi:10.1038/nature11346 RNA interference in Kasalath RNA interference downregulate the expression of Pstol1 in Kasalath caused a significant reduction in root number and root surface area, PSTOL1 is an enhancer of root growth! R Gamuyao et al. Nature 488, 535-539 (2012) doi:10.1038/nature11346 13/16

R Gamuyao et al. Nature 488, 535-539 (2012) doi:10.1038/nature11346 How PSTOL1 enhance root growth? The expression of PSTOL1 during root development Main root system Parenchymatic cells Crown root Crown Root Primordia Emerging crown roots Further, in order to find out how pstol1 enhance root growth. The expression of Pstol1 during root development was analyzed by expressing the GUS reporter gene under the control of native Pstol1 promoter in transgenic plants. Specific GUS staining was detected in stem nodes, where crown root was formed, which constitute the main root system. Within the nodes, GUS staining was restricted to Crown Root Primordia and parenchymatic cells. In older plants, GUS staining was additionally detected in the cells surrounding vascular bundles. However, no GUS staining was observed in older and emerging crown root or the seminal root. So, taken together, the data indicated that pstol1 is a regulator of early crown root development and root growth in rice vascular bundles PSTOL1 is a regulator of early crown root development and root growth R Gamuyao et al. Nature 488, 535-539 (2012) doi:10.1038/nature11346 14/16

PSTOL1 putative downstream genes 23 genes related to root growth and stress response with constitutively higher or lower expression in the transgenic plants were identified R Gamuyao et al. Nature 488, 535-539 (2012) doi:10.1038/nature11346 15/16

PSTOL1 putative downstream genes delay leaf senescence in rice a positive regulator of root cell differentiation 21 of these differentially expressed genes co-localize with QTLs related to drought tolerance and root growth R Gamuyao et al. Nature 488, 535-539 (2012) doi:10.1038/nature11346 16/16