A newly evolved rice-specific gene JAUP1 regulates jasmonate biosynthesis and signalling to promote root development and multi-stress tolerance.

Root architecture and function are critical for plants to secure water and nutrient supply from the soil, but environmental stresses alter root development. The phytohormone jasmonic acid (JA) regulates plant growth and responses to wounding and other stresses, but its role in root development for adaptation to environmental challenges had not been well investigated. We discovered a novel JA Upregulated Protein 1 gene (JAUP1) that has recently evolved in rice and is specific to modern rice accessions. JAUP1 regulates a self-perpetuating feed-forward loop to activate the expression of genes involved in JA biosynthesis and signalling that confers tolerance to abiotic stresses and regulates auxin-dependent root development. Ectopic expression of JAUP1 alleviates abscisic acid- and salt-mediated suppression of lateral root (LR) growth. JAUP1 is primarily expressed in the root cap and epidermal cells (EPCs) that protect the meristematic stem cells and emerging LRs. Wound-activated JA/JAUP1 signalling promotes crosstalk between the root cap of LR and parental root EPCs, as well as induces cell wall remodelling in EPCs overlaying the emerging LR, thereby facilitating LR emergence even under ABA-suppressive conditions. Elevated expression of JAUP1 in transgenic rice or natural rice accessions enhances abiotic stress tolerance and reduces grain yield loss under a limited water supply. We reveal a hitherto unappreciated role for wound-induced JA in LR development under abiotic stress and suggest that JAUP1 can be used in biotechnology and as a molecular marker for breeding rice adapted to extreme environmental challenges and for the conservation of water resources.

Doping effects of CuO additives on the properties of low-temperature-sintered PMnN-PZT-based piezoelectric ceramics and their applications on surface acoustic wave devices.

To develop the anisotropic ceramic substrate with low sintering temperature for surface acoustic wave (SAW) applications, the low cost and feasible material with moderate piezoelectric properties, good dielectric properties, and higher Curie temperature were explored. The piezoelectric ceramics with compositions of Pb[(Mn(1/3)Nb(2/3))(0.06-) (Zr(0.52)Ti(0.48))0.94] O(3) (PMnN-PZT) + 0.5 wt.% PbO + x wt.% CuO (0.05 = x = 0.3) had been prepared by the conventional mixed-oxides method. CuO dopants were used as the sintering aid to improve the bulk density under low sintering temperature (i.e., 980-1040 degrees C). The phase structures, microstructures, frequency behavior of dielectric properties (up to 50 MHz), piezoelectric properties, ferroelectric properties, and temperature stability with the amount of CuO additive were systematically investigated. Experimental results showed that the sintering temperature could be lowered down to 1020 degrees C and still keep reasonably good piezoelectric activity (i.e., high electromechanical coupling factor (k(p)), (k(t)) and dielectric and ferroelectric properties. The preferable composition, obtained at x = 0.1, presented the values of the electromechanical coupling factor (k(p)) (k(t)), mechanical quality factor (Q(m)), piezoelectric charge constant (d(33)), dielectric constant, dielectric loss, temperature coefficient of resonant frequency (TCF(B)), and Curie point (T(c)) of 0.54, 0.48, 850, 238 pc/N, 1450, 0.0023, 1.1 kV/mm, 26 coul/cm(2), -150 ppm/ degrees C, and 348 degrees C. Using this developed low-temperature-sintered material to make the piezoelectric substrate, the SAW filter was fabricated and its properties were measured. Results showed that this device possessed very high value of k(2)(7.13%) with a good TCF (-40.15 ppm/ degrees C), and a surface wave velocity (V(P)) of 2196 m/s.

Transactivation of protein expression by rice HSP101 in planta and using Hsp101 as a selection marker for transformation.

Plant HSP101 has dual activities, first, in conferring thermotolerance, and secondly, in serving as a translational activator. In this study, we introduced Oryza sativa Hsp101 (osHsp101) cDNA into tobacco by Agrobacterium-mediated transformation. Stable integration and expression of the transgene into the tobacco genome was demonstrated by Southern and Western blot analysis. Overexpression of osHSP101 had no noticeable effect on growth or development of the transgenic plants. Homozygous T(2) transgenic plants with overexpressed osHSP101 survived heat treatment better than untransformed control plants. In addition, taking advantage of conferring basal thermotolerance by plant HSP101, we were able to demonstrate the feasibility of using osHsp101 as a selection marker and select the transformants under high temperature in tobacco leaf disc transformation mediated by Agrobacterium. Furthermore, transgenic tobacco plants with overexpressed osHSP101 were able to enhance luciferase expression up to 2.9-fold more than untransformed plants in the progeny of reciprocally crossed with omega-luciferase reporter lines.