Adding Linkability to Ring Signatures with One-Time Signatures

We propose a generic construction that adds linkability to any ring signature scheme with one-time signature scheme. Our construction has both theoretical and practical interest. In theory, the construction gives a formal and cleaner description for constructing linkable ring signature from ring signature directly. In practice, the transformation incurs a tiny overhead in size and running time. By instantiating our construction using the ring signature scheme (ACNS 2019) and the one-time signature scheme (TCHES 2018), we obtain a lattice-based linkable ring signature scheme whose signature size is logarithmic in the number of ring members. This scheme is practical, especially the signature size is very short: for $2^{30}$ ring members and 100 bit security, our signature size is only 4 MB. In addition, when proving the linkability we develop a new proof technique in the random oracle model, which might be of independent interes

Sugarcane (Saccharum X officinarum): A Reference Study for the Regulation of Genetically Modified Cultivars in Brazil

Global interest in sugarcane has increased significantly in recent years due to its economic impact on sustainable energy production. Sugarcane breeding and better agronomic practices have contributed to a huge increase in sugarcane yield in the last 30 years. Additional increases in sugarcane yield are expected to result from the use of biotechnology tools in the near future. Genetically modified (GM) sugarcane that incorporates genes to increase resistance to biotic and abiotic stresses could play a major role in achieving this goal. However, to bring GM sugarcane to the market, it is necessary to follow a regulatory process that will evaluate the environmental and health impacts of this crop. The regulatory review process is usually accomplished through a comparison of the biology and composition of the GM cultivar and a non-GM counterpart. This review intends to provide information on non-GM sugarcane biology, genetics, breeding, agronomic management, processing, products and byproducts, as well as the current technologies used to develop GM sugarcane, with the aim of assisting regulators in the decision-making process regarding the commercial release of GM sugarcane cultivars

ABI5 interacts with abscisic acid signaling effectors in rice protoplasts

Abscisic acid (ABA) regulates seed maturation, germination, and adaptation of vegetative tissues to environmental stresses. The mechanisms of ABA action and the specificity conferred by signaling components in overlapping pathways are not completely understood. The ABI5 gene (ABA insensitive 5) of Arabidopsis encodes a basic leucine zipper factor required for ABA response in the seed and vegetative tissues. Using transient gene expression in rice protoplasts, we provide evidence for the functional interactions of ABI5 with ABA signaling effectors VP1 (viviparous 1) and ABI1 (ABA insensitive 1). Co-transformation experiments with ABI5 cDNA constructs resulted in specific transactivation of the ABA-inducible wheat Em, Arabidopsis AtEm6, bean beta-Phaseolin, and barley HVA1 and HVA22 promoters. Furthermore, ABI5 interacted synergistically with ABA and co-expressed VP1, indicating that ABI5 is involved in ABA-regulated transcription mediated by VP1. ABI5-mediated transactivation was inhibited by overexpression of abi1-1, the dominant-negative allele of the protein phosphatase ABI1, and by 1-butanol, a competitive inhibitor of phospholipase D involved in ABA signaling. Lanthanum, a trivalent ion that acts as an agonist of ABA signaling, potentiated ABI5 transactivation. These results demonstrate that ABI5 is a key target of a conserved ABA signaling pathway in plants

Homodimerization of the deleted in liver cancer 2 (DLC2) is not mediated by the SAM domain

Session - Signal TransductionDeleted in liver cancer 2 (DLC2) is a novel tumor suppressorgene which is found to be frequently deleted in hepatocellularcarcinoma. Although DLC2 is consisted of a RhoGAP homologydomain, a START domain and a sterile-a-motif (SAM) domain,the role of DLC2 in cellular function remains elusive. To gaininsight on the function of DLC2, we expressed and purified arecombinant13C and15N doubled DLC2 SAM domain. Circulardichromism analysis showed that DLC2 SAM contains high heli-ces. We further determined the structure of the DLC2 SAMdomain by 2D and 3D NMR experiments together with simula-ted annealing calculations. Our data revealed that the structureof DLC2 SAM is slightly different from other known SAMdomains and adapts a monomeric structure with four alpha heli-ces in solution. Consistent with the structural data, cross-linkingexperiment also suggested that DLC SAM exists in predomin-antly monomeric form in vitro. On the other hand, co-immuno-precipitation experiments suggested that the DLC2 protein ishomodimerized. Analysis of the deletion mutants revealed thatthe homodimerization is not mediated by the SAM domain, butthrough a distinct region on the DLC2 protein.link_to_OA_fulltex

Structural study of the SAM domain of the deleted in liver cancer 2 (DLC2)

Some authors have demonstrated recently the capability of microwave imaging of subsurface defects and material characteristics by scanning a suitably excited open-ended rectangular waveguide over a multi-layered composite [1,2]. This near-field approach of microwave NDE is in some aspects similar to the conventional eddy-current based techniques for defect detection and imaging in metals [3]. Of course, in non-metallic materials, it is the discontinuities in the dielectric property, instead of the electrical conductivity, that gives rise to the defect signal. Bahr [4,5] has reported various techniques for the detection, discrimination, and processing of microwave signals, which are also applicable in the lower frequency regime typical of eddy current testing

Solution structures and dynamics of the sterile α Motif (SAM) domain of the deleted in liver cancer 2 (DLC2): a monomeric structure with membrane-binding properties

The Deleted in Liver Cancer 2 (DLC2) gene encodes a Rho GTPase-activating protein (GAP) with growth suppressor function. In addition to the RhoGAP domain, this molecule also contains a sterile α motif (SAM) and a lipid-binding StAR-related lipid-transfer (START) domain. To gain an insight into the function of DLC2, we have expressed and purified a recombinant 13C/15N doubly-labeled DLC2 SAM domain. The three-dimensional solution structure and dynamics of the SAM domain of DLC2, DLC2-SAM, were investigated by NMR spectroscopy together with molecular dynamic simulated annealing. We showed that DLC2-SAM is distinct from all other known SAM domains by the presence of a four-helix bundle. The spatial arrangement of four α-helices is also unique. Backbone dynamics studies showed a restricted motion of four helices and a high mobility of the N-and C-termini as well as loops. Although it has been shown that some members of the SAM domain family can form dimers and oligomers, both NMR and biochemical analyses indicated that DLC2-SAM exists as a monomer in solution. We also examined the interaction of DLC2-SAM domain with sodium dodecyl sulfate (SDS) micelles by NMR and CD spectroscopic techniques. 2D [1H,15N] HSQC spectra of DLC2-SAM in the presence of SDS displayed shifts of most residues although still well dispersed, in agreement with slightly decreased α-helical content based on CD spectra of DLC2-SAM in the absence and presence of SDS, suggesting that DLC2-SAM may interact with membrane lipids in vivo with secondary structure changes of the protein. Finally, we demonstrated that DLC2-SAM is dispensable for the self association of full-length DLC2 in vivo