Improving plant drought tolerance and growth under water limitation through combinatorial engineering of signalling networks

Agriculture is by far the biggest water consumer on our planet, accounting for 70 per cent of all freshwater withdrawals. Climate change and a growing world population increase pressure on agriculture to use water more efficiently ('more crop per drop'). Water-use efficiency (WUE) and drought tolerance of crops are complex traits that are determined by many physiological processes whose interplay is not well understood. Here, we describe a combinatorial engineering approach to optimize signalling networks involved in the control of stress tolerance. Screening a large population of combinatorially transformed plant lines, we identified a combination of calcium-dependent protein kinase genes that confers enhanced drought stress tolerance and improved growth under water-limiting conditions. Targeted introduction of this gene combination into plants increased plant survival under drought and enhanced growth under water-limited conditions. Our work provides an efficient strategy for engineering complex signalling networks to improve plant performance under adverse environmental conditions, which does not depend on prior understanding of network function

ABA inhibits myristoylation and induces shuttling of the RGLG1 E3 ligase to promote nuclear degradation of PP2CA

[EN] Hormone- and stress-induced shuttling of signaling or regulatory proteins is an important cellular mechanism to modulate hormone signaling and cope with abiotic stress. Hormone-induced ubiquitination plays a crucial role to determine half-life of key negative regulators of hormone signaling. For ABA signaling, degradation of clade A PP2Cs, such as PP2CA or ABI1, is a complementary mechanism to PYR/PYL/RCAR-mediated inhibition of PP2C activity. ABA promotes the degradation of PP2CA through the RGLG1 E3 ligase, although it is not known how ABA enhances the interaction of RGLG1 with PP2CA given they are predominantly found in plasma membrane and nucleus, respectively. We demonstrate that ABA modifies the subcellular localization of RGLG1 and promotes nuclear interaction with PP2CA. We found RGLG1 is myristoylated in vivo, which facilitates its attachment to plasma membrane. ABA inhibits myristoylation of RGLG1 through downregulation of Nmyristoyltransferase1 (NMT1) and promotes nuclear translocation of RGLG1 in a cycloheximide-insensitive manner. Enhanced nuclear recruitment of the E3 ligase was also promoted by increasing PP2CA protein levels and the formation of RGLG1-receptor-phosphatase complexes. We show that RGLG1Gly2Ala -mutated in the Nterminal myristoylation site- shows constitutive nuclear localization and causes enhanced response to ABA and salt/osmotic stress. RGLG1/5 can interact with certain monomeric ABA receptors, which facilitates the formation of nuclear complexes such as RGLG1-PP2CA-PYL8. In summary, we provide evidence that an E3 ligase can dynamically re-localize in response to both ABA and increased levels of its target, which reveals a mechanism to explain how ABA enhances RGLG1-PP2CA interaction and hence PP2CA degradation.Work in P.L.R.'s laboratory was supported by the Ministerio de Ciencia e Innovacion, Fondo Europeo de Desarrollo Regional and Consejo Superior de Investigaciones Cientificas through grants BIO2014-52537-R and BIO2017-82503-R. This work was also funded by grants from the Deutsche Forschungsgemeinschaft (DFG) Ku931/4-1 to J. K., and BA4742/1-2 to O.B. B.B. was funded by Programa VALi+ d GVA APOSTD/2017/039. J.J. was supported by an FPI contract from MINECOBelda Palazón, B.; Julian, J.; Coego, A.; Wu, Q.; Zhang, X.; Batistic, O.; Alquraishi, SA.... (2019). ABA inhibits myristoylation and induces shuttling of the RGLG1 E3 ligase to promote nuclear degradation of PP2CA. 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Degradation of the ABA co-receptor ABI1 by PUB12/13 U-box E3 ligases. Nature Communications, 6(1). doi:10.1038/ncomms9630Kuhn, J. M., Boisson-Dernier, A., Dizon, M. B., Maktabi, M. H., & Schroeder, J. I. (2005). The Protein Phosphatase AtPP2CA Negatively Regulates Abscisic Acid Signal Transduction in Arabidopsis, and Effects of abh1 on AtPP2CA mRNA  . Plant Physiology, 140(1), 127-139. doi:10.1104/pp.105.070318Lee, S. C., Lan, W., Buchanan, B. B., & Luan, S. (2009). A protein kinase-phosphatase pair interacts with an ion channel to regulate ABA signaling in plant guard cells. Proceedings of the National Academy of Sciences, 106(50), 21419-21424. doi:10.1073/pnas.0910601106Lee, H.-J., Park, Y.-J., Seo, P. J., Kim, J.-H., Sim, H.-J., Kim, S.-G., & Park, C.-M. (2015). Systemic Immunity Requires SnRK2.8-Mediated Nuclear Import of NPR1 in Arabidopsis. The Plant Cell, 27(12), 3425-3438. doi:10.1105/tpc.15.00371Leitner, J., Petrasek, J., Tomanov, K., Retzer, K., Parezova, M., Korbei, B., … Luschnig, C. (2012). Lysine63-linked ubiquitylation of PIN2 auxin carrier protein governs hormonally controlled adaptation of Arabidopsis root growth. Proceedings of the National Academy of Sciences, 109(21), 8322-8327. doi:10.1073/pnas.1200824109Li, W., & Schmidt, W. (2010). A lysine-63-linked ubiquitin chain-forming conjugase, UBC13, promotes the developmental responses to iron deficiency in Arabidopsis roots. The Plant Journal, 62(2), 330-343. doi:10.1111/j.1365-313x.2010.04150.xLumba, S., Cutler, S., & McCourt, P. (2010). Plant Nuclear Hormone Receptors: A Role for Small Molecules in Protein-Protein Interactions. Annual Review of Cell and Developmental Biology, 26(1), 445-469. doi:10.1146/annurev-cellbio-100109-103956Lynch, T., Erickson, B. J., & Finkelstein, R. R. (2012). Direct interactions of ABA-insensitive(ABI)-clade protein phosphatase(PP)2Cs with calcium-dependent protein kinases and ABA response element-binding bZIPs may contribute to turning off ABA response. Plant Molecular Biology, 80(6), 647-658. doi:10.1007/s11103-012-9973-3Majeran, W., Le Caer, J.-P., Ponnala, L., Meinnel, T., & Giglione, C. (2018). Targeted Profiling of Arabidopsis thaliana Subproteomes Illuminates Co- and Posttranslationally N-Terminal Myristoylated Proteins. The Plant Cell, 30(3), 543-562. doi:10.1105/tpc.17.00523Moes, D., Himmelbach, A., Korte, A., Haberer, G., & Grill, E. (2008). Nuclear localization of the mutant protein phosphatase abi1 is required for insensitivity towards ABA responses in Arabidopsis. The Plant Journal, 54(5), 806-819. doi:10.1111/j.1365-313x.2008.03454.xMoreno-Alvero, M., Yunta, C., Gonzalez-Guzman, M., Lozano-Juste, J., Benavente, J. L., Arbona, V., … Albert, A. (2017). Structure of Ligand-Bound Intermediates of Crop ABA Receptors Highlights PP2C as Necessary ABA Co-receptor. Molecular Plant, 10(9), 1250-1253. doi:10.1016/j.molp.2017.07.004NAKAGAWA, T., SUZUKI, T., MURATA, S., NAKAMURA, S., HINO, T., MAEO, K., … ISHIGURO, S. (2007). Improved Gateway Binary Vectors: High-Performance Vectors for Creation of Fusion Constructs in Transgenic Analysis of Plants. Bioscience, Biotechnology, and Biochemistry, 71(8), 2095-2100. doi:10.1271/bbb.70216Peirats-Llobet, M., Han, S.-K., Gonzalez-Guzman, M., Jeong, C. W., Rodriguez, L., Belda-Palazon, B., … Rodriguez, P. L. (2016). A Direct Link between Abscisic Acid Sensing and the Chromatin-Remodeling ATPase BRAHMA via Core ABA Signaling Pathway Components. Molecular Plant, 9(1), 136-147. doi:10.1016/j.molp.2015.10.003Pierre, M., Traverso, J. A., Boisson, B., Domenichini, S., Bouchez, D., Giglione, C., & Meinnel, T. (2007). N-Myristoylation Regulates the SnRK1 Pathway inArabidopsis. 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The influence of complex additives on the sulphate resistance of concrete

The paper considers the influence of complex additives on the properties of concrete. As mineral additive microsilica is proposed, it contributes to the corrosion resistance of concrete. Combined introduction of mineral and chemical additives will increase the sulfate resistance of concrete structures, which will preserve the durability of facilities and reduce energy and resource costs.В работе рассмотрено влияние комплексной добавки на свойства бетона. В качестве минеральной добавки предложен микрокремнезем, который способствует коррозионной стойкости бетона. Совместное введение минеральной и химической добавки увеличит сульфатостойкость бетонных конструкций, что позволит сохранить долговечность объектов и снизить энерго- и ресурсозатраты

Genome landscapes and bacteriophage codon usage

Across all kingdoms of biological life, protein-coding genes exhibit unequal usage of synonmous codons. Although alternative theories abound, translational selection has been accepted as an important mechanism that shapes the patterns of codon usage in prokaryotes and simple eukaryotes. Here we analyze patterns of codon usage across 74 diverse bacteriophages that infect E. coli, P. aeruginosa and L. lactis as their primary host. We introduce the concept of a `genome landscape,' which helps reveal non-trivial, long-range patterns in codon usage across a genome. We develop a series of randomization tests that allow us to interrogate the significance of one aspect of codon usage, such a GC content, while controlling for another aspect, such as adaptation to host-preferred codons. We find that 33 phage genomes exhibit highly non-random patterns in their GC3-content, use of host-preferred codons, or both. We show that the head and tail proteins of these phages exhibit significant bias towards host-preferred codons, relative to the non-structural phage proteins. Our results support the hypothesis of translational selection on viral genes for host-preferred codons, over a broad range of bacteriophages.Comment: 9 Color Figures, 5 Tables, 53 Reference

Intact landscape promotes gene flow and low genetic structuring in the threatened Eastern Massasauga Rattlesnake

Genetic structuring of wild populations is dependent on environmental, ecological, and life-history factors. The specific role environmental context plays in genetic structuring is important to conservation practitioners working with rare species across areas with varying degrees of fragmentation. We investigated fine-scale genetic patterns of the federally threatened Eastern Massasauga Rattlesnake (Sistrurus catenatus) on a relatively undisturbed island in northern Michigan, USA. This species often persists in habitat islands throughout much of its distribution due to extensive habitat loss and distance-limited dispersal. We found that the entire island population exhibited weak genetic structuring with spatially segregated variation in effective migration and genetic diversity. The low level of genetic structuring contrasts with previous studies in the southern part of the species' range at comparable fine scales (~7 km), in which much higher levels of structuring were documented. The island population's genetic structuring more closely resembles that of populations from Ontario, Canada, that occupy similarly intact habitats. Intrapopulation variation in effective migration and genetic diversity likely corresponds to the presence of large inland lakes acting as barriers and more human activity in the southern portion of the island. The observed genetic structuring in this intact landscape suggests that the Eastern Massasauga is capable of sufficient interpatch movements to reduce overall genetic structuring and colonize new habitats. Landscape mosaics with multiple habitat patches and localized barriers (e.g., large water bodies or roads) will promote gene flow and natural colonization for this declining species

EFFECTIVE WAYS TO REDUCE EFFLORESCENCE IN CONCRETE

The main reasons of efflorescence worsening the appearance of building objects are considered. Efflorescence on concrete and brick also result in considerable stress that causes the wall degradation. Ways to prevent the formation of efflorescence allow maintaining the object durability and hence significantly reducing energy and resource consumption are studied.Рассмотрены основные причины образования высолов, ухудшающие внешний вид строительных объектов. Высолы на бетоне и кирпиче также служат причиной появления значительных механических напряжений, от которых с течением времени стены начинают разрушаться. Изучены пути предупреждения образования высолов, позволяющие сохранить долговечность объектов, тем самым существенно снизить энерго- и ресурсозатраты

Multi-objective genetic algorithm applied to spectroscopic ellipsometry of organic-inorganic hybrid planar waveguides

The applicably of multi-objective optimization to ellipsometric data analysis is presented and a method to handle complex ellipsometric problems such as multi sample or multi angle analysis using multi-objective optimization is described. The performance of a multi-objective genetic algorithm (MOGA) is tested against a single objective common genetic algorithm (CGA). The procedure is applied to the characterization (refractive index and thickness) of planar waveguides intended for the production of optical components prepared sol-gel derived organic-inorganic hybrids, so-called di-ureasils, modified with zirconium tetrapropoxide, Zr(OPr(n))(4) deposited on silica on silicon substrates. The results show that for the same initial conditions, MOGA performs better than the CGA, showing a higher success rate in the task of finding the best final solution. (C) 2010 Optical Society of AmericaFCTFEDERPTDC/CTM/72093/2006SFRH/BD/41943/2007MP070

The RNA-binding landscape of HAX1 protein indicates its involvement in translation and ribosome assembly

HAX1 is a human protein with no known homologues or structural domains. Mutations in the HAX1 gene cause severe congenital neutropenia through mechanisms that are poorly understood. Previous studies reported the RNA-binding capacity of HAX1, but the role of this binding in physiology and pathology remains unexplained. Here, we report the transcriptome-wide characterization of HAX1 RNA targets using RIP-seq and CRAC, indicating that HAX1 binds transcripts involved in translation, ribosome biogenesis, and rRNA processing. Using CRISPR knockouts, we find that HAX1 RNA targets partially overlap with transcripts downregulated in HAX1 KO, implying a role in mRNA stabilization. Gene ontology analysis demonstrated that genes differentially expressed in HAX1 KO (including genes involved in ribosome biogenesis and translation) are also enriched in a subset of genes whose expression correlates with HAX1 expression in four analyzed neoplasms. The functional connection to ribosome biogenesis was also demonstrated by gradient sedimentation ribosome profiles, which revealed differences in the small subunit:monosome ratio in HAX1 WT/KO. We speculate that changes in HAX1 expression may be important for the etiology of HAX1-linked diseases through dysregulation of translation

High-dose cisplatin in advanced head and neck cancer

In 22 patients with advanced squamous cell carcinoma of the head and neck we evaluated the efficacy and toxicity of 200 mg/m 2 cisplatin administered in 3% NaCl with vigorous hydration. Six patients had previously untreated stage IV disease and 16 patients had recurrent disease, including eight with prior chemotherapy including low-dose cisplatin and carboplatin. Cisplatin was administered as a brief infusion, either 40 mg/m 2 /day × 5 or 50mg/m 2 /day × 4, every 28 days. Objective responses were observed in 16 of 22 (73%) patients, including 5 of 6 (83%) previously untreated patients and 11 of 16 (69%) patients with recurrent disease. This included two comoplete responses, one confirmed pathologically. Fifty-seven courses of drug were administered and toxicity was monitored with serial creatinine clearance determinations, audiograms, and sensorimotor exams. Neuropathy and ototoxicity were dose-limiting and led to the stopping of treatment in 12 of the 16 responders after one to four courses (median three courses). Only two responding patients continued treatment until disease progression occurred at 3 and 4 months after achieving maximum response. Acute, transient nephrotoxicity occurred in four patients; two were retreated. Moderate myelosuppression occurred in all patients but was not treatment-limiting. For most patients the maximally tolerated number of courses was three. The median survival time was 33.5 weeks for recurrent disease patients, 108 weeks for newly diagnosed patients. This regimen is not recommended for the palliation of recurrent disease. However, the very high response rate suggests that high-dose cisplatin may have a useful role in induction or adjuvant chemotherapy regimens.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46916/1/280_2004_Article_BF00254569.pd