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Key message: Induced mutations in the waxy locus in rice endosperm did not abolish GBSS activity completely. Compensatory mechanisms in endosperm and leaves caused a major reprogramming of the starch biosynthetic machinery. Abstract: The mutation of genes in the starch biosynthesis pathway has a profound effect on starch quality and quantity and is an important target for plant breeders. Mutations in endosperm starch biosynthetic genes may impact starch metabolism in vegetative tissues such as leaves in unexpected ways due to the complex feedback mechanisms regulating the pathway. Surprisingly this aspect of global starch metabolism has received little attention. We used CRISPR/Cas9 to introduce mutations affecting the Waxy (Wx) locus encoding granule-bound starch synthase I (GBSSI) in rice endosperm. Our specific objective was to develop a mechanistic understanding of how the endogenous starch biosynthetic machinery might be affected at the transcriptional level following the targeted knock out of GBSSI in the endosperm. We found that the mutations reduced but did not abolish GBSS activity in seeds due to partial compensation caused by the upregulation of GBSSII. The GBSS activity in the mutants was 61–71% of wild-type levels, similarly to two irradiation mutants, but the amylose content declined to 8–12% in heterozygous seeds and to as low as 5% in homozygous seeds, accompanied by abnormal cellular organization in the aleurone layer and amorphous starch grain structures. Expression of many other starch biosynthetic genes was modulated in seeds and leaves. This modulation of gene expression resulted in changes in AGPase and sucrose synthase activity that explained the corresponding levels of starch and soluble sugars., We thank Dr. Caixia Gao (Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China) for providing pJIT163-2NLSCas9 containing the rice codonoptimized cas9, and the empty pU3-gRNA vector. We thank Professor Kimiko Itoh, Graduate School of Science and Technology (Niigata University, Japan) for providing the KUR and Musa Wx lines. This work was supported by funding from the Spanish Ministry of Economy and Competitiveness (MINECO) (BIO2014-54426), and a Juan de la Cierva fellowship to GF (IJCI-2014-19528). LP is the recipient of MINECO fellowship. ES is the recipient of a PhD fellowship from the University of Lleida (BIO2014-54441-P).

We report on a series of experiments that examine bidding behavior in first-price sealed bid auctions with symmetric and asymmetric bidders.To study the extent of strategic behavior, we use an experimental design that elicits bidders complete bid functions in each round (auction) of the experiment.In the aggregate, behavior is consistent with the basic equilibrium predictions for risk neutral or homogenous risk averse bidders (extent of bid shading, average seller s revenues and deviations from equilibrium).However, when we look at the extent of best reply behavior and the shape of bid functions, we find that individual behavior is not in line with the received equilibrium models, although it exhibits strategic sophistication.

This article 'Expression of an engineered cysteine proteinase inhibitor (Oryzacystatin-186) in transgenic rice plants' appeared in the International Rice Research Notes series, created by the International Rice Research Institute (IRRI) to expedite communication among scientists concerned with the development of improved technology for rice and rice-based systems. The series is a mechanism to help scientists keep each other informed of current rice research findings. The concise scientific notes are meant to encourage rice scientists to communicate with one another to obtain details on the research reported.

To estimate the applicability of potential sites for insertion of orthodontic mini-implants (OMIs) by a systematic review of studies that used computed tomography (CT) or cone beam CT to evaluate anatomical bone quality and quantity parameters, such as bone thickness, available space, and bone density.

To develop a theoretical aepidemiological model for the prediction of orthodontic workforce needs, based on regional orthodontic treatment need.Data were collected for the number of children between the ages of 8-11 years attending primary schools in Greece, within each regional division. Treatment need of the children was estimated using the Index of Orthodontic Treatment Need (IOTN). Demographics of practicing orthodontists in Greece were also collected. Based on the distribution of orthodontists and the number of children per region who would potentially receive orthodontic treatment (IOTN 3-5), the presence and distribution of orthodontic manpower was evaluated.Overall orthodontic manpower is sufficient for Greece's needs with an excess of 55 orthodontists. Distribution however is not uniform, and this ranges from a large underrepresentation of orthodontists in the Ionian Islands (47% of those required) to an overrepresentation in the Attica region (183% of those required).Based on the present theoretical model, Greece has an adequate overall orthodontic workforce for coverage of the population needs, but with large regional variations indicating that some regions have a surplus while others a shortage of orthodontists. The present model seems suitable for the calculation of regional orthodontic workforce coverage of a population.

Summary. Transglutaminases have a range of catalytic activities, most of which concern the post-translational modification of proteins. The most important of these activities, both in terms of biology and biotechnology, is the cross-linking of proteins into large supramolecular networks. The widespread use of transglutaminases in research, medicine and industry has increased the demand for an inexpensive, efficient and safe source of recombinant enzymes. We describe initial results concerning the production of a mammalian transglutaminase in transgenic rice plants as a first step towards the large-scale molecular farming of this enzyme.