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The meiotic TopoVI B subunit (MTopVIB) plays an essential role in double-strand break formation in mouse (Mus musculus), Arabidopsis (Arabidopsis thaliana), and rice (Oryza sativa), and recent work reveals that rice MTopVIB also plays an unexpected role in meiotic bipolar spindle assembly, highlighting multiple functions of MTopVIB during rice meiosis. In this work, we characterized the meiotic TopVIB in maize (Zea mays; ZmMTOPVIB). The ZmmtopVIB mutant plants exhibited normal vegetative growth but male and female sterility. Meiotic double-strand break formation was abolished in mutant meiocytes. Despite normal assembly of axial elements, mutants showed severely affected synapsis and disrupted homologous pairing. Importantly, we showed that bipolar spindle assembly was also affected in ZmmtopVIB, resulting in triad and polyad formation. Overall, our results demonstrate that ZmMTOPVIB plays critical roles in double-strand break formation and homologous recombination. In addition, our results suggest that the function of MTOPVIB in bipolar spindle assembly is likely conserved across different monocots.

The programmed formation of DNA double-strand breaks (DSBs) during early meiosis is catalyzed by SPO11, a conserved ortholog to the A subunit of an archaeal topoisomerase VI (TopoVI) which functions as a hetero-tetramer comprising two A and two B subunits. An essential role of the meiotic TopoVI B subunit (TopVIB) in DSB formation has been reported in mouse, Arabidopsis and rice. Very recently, riceMTopVIBwas revealed to have an unexpected role in meiotic bipolar spindle assembly, highlighting multiple functions ofMTopVIBduring rice meiosis. In this work, the meioticTopVIBin maize (ZmMTOPVIB) was characterized. TheZmmtopVIBmutant plants exhibited normal vegetative growth but male and female sterility. DSB formation is abolished in mutant meiocytes. Despite normal assembly of axial elements, synapsis was severely affected and homologous pairing was disrupted in mutants. Importantly, we showed that bipolar spindle assembly was also affected inZmmtopVIB, resulting in triad and polyad formation. Overall, our results demonstrate thatZmMTOPVIBplays critical roles in DSB formation and homologous recombination. In addition, the newly-discovered function ofMTOPVIBin bipolar spindle assembly is likely conserved across different monocots.One-sentence summaryThe dual roles ofMTOPVIBin regulating meiotic DSB formation and bipolar spindle assembly are evolutionarily conserved in monocot plants.

Plakin proteins form connections that link the cell membrane to the intermediate filament cytoskeleton. Their interactions are mediated by a highly conserved linker domain through an unresolved mechanism. Here analysis of the human periplakin linker domain structure reveals a bi-lobed module transected by an electropositive groove. Key basic residues within the periplakin groove are vital for co-localization with vimentin in human cells and compromise direct binding which also requires acidic residues D176 and E187 in vimentin. We propose a model whereby basic periplakin linker domain residues recognize acidic vimentin side chains and form a complementary binding groove. The model is shared amongst diverse linker domains and can be used to investigate the effects of pathogenic mutations in the desmoplakin linker associated with arrhythmogenic right ventricular cardiomyopathy. Linker modules either act solely or collaborate with adjacent plakin repeat domains to create strong and adaptable tethering within epithelia and cardiac muscle., Odinstova, Mohammed, Trieber et al. use structure-based mutagenesis to identify key residues in human periplakin and desmoplakin linker modules required for co-localization with vimentin intermediate filaments. They show that vimentin D176 and E187 are required for direct binding with the periplakin linker.

In smart grids, demand-side management (DSM) is one of the important mechanism since it can reduce the total electricity cost of each customer, meanwhile alleviates the aggregate peak-to-average ratio (PAR) subject to real-time pricing (RTP) policy. On the other hand, with the growth of bidirectional charging/discharging Plug-in Electric vehicles (PEV), the capability of storing electrical energy for load shifting and energy sharing among users may take smart grid to a next level. In the viewpoint of a community, we design a fairness strategy and apply particle swarm optimization (PSO) to get the near optimal sharing schedule within community and share PEV’s battery with neighbors to reduce the total electricity cost and peak-to-average ratio (PAR). On the other hand, we try to utilize the PEVs which park at the commercial building during working hour to be involved with part of the building’s power consumption. In the simulation, we have collected ten daily activity profiles from ten different people to represent the residents in the community and use the hourly load profile data from the Office of Energy Efficiency & Renewable Energy (EERE) for a commercial sector. The results show that the proposed DSM system not only reduces the electricity cost for each household but also reduces the PAR of the community. Moreover, for the commercial building, the proper rearrangement of PEVs’ behavior also helps to reduce the total electricity cost and PAR.

The overall game plan of "One Day"

In smart grids, demand-side management (DSM) is one of the important function for both customers and utility, since it can reduce the total electricity cost of each customer, meanwhile, alleviate the aggregate peak-to-average ratio (PAR) subjected to real-time pricing (RTP) policy. On the other hand, while bidirectional charging/discharging Plug-in Electric vehicles (PEV) become more general, the capability of storing electrical energy for load shifting may take smart grid to a next level. This works aims at integrating PEV into DSM system, which considers renewable energy and energy trading as well. As it comes to community, we design a fairness strategy to share PEV's battery with neighbors to reduce the total electric cost and peak to average ratio (PAR). The simulation results show that the proposed DSM system not only meets the requirement of the PEV and reduce the cost for each household but also creates a win-win situation through the energy trading among homes based on consideration of both fairness and privacy protection in a residential community.

Summary In collective cell migration, directional protrusions orient cells in response to external cues, which requires coordinated polarity among the migrating cohort. However, the molecular mechanism has not been well defined. Drosophila border cells (BCs) migrate collectively and invade via the confined space between nurse cells, offering an in vivo model to examine how group polarity is organized. Here, we show that the front/back polarity of BCs requires Rap1, hyperactivation of which disrupts cluster polarity and induces misoriented protrusions and loss of asymmetry in the actin network. Conversely, hypoactive Rap1 causes fewer protrusions and cluster spinning during migration. A forward genetic screen revealed that downregulation of the Hippo (Hpo) pathway core components hpo or mats enhances the Rap1 V12 -induced migration defect and misdirected protrusions. Mechanistically, association of Rap1 V12 with the kinase domain of Hpo suppresses its activity, which releases Hpo signaling-mediated suppression of F-actin elongation, promoting cellular protrusions in collective cell migration.

There were several attempts recently in making a combination of fuzzy logic and neural networks for better performance in expert systems. Since all operations involve fuzzy set theory, the amount of calculation per inference increases dramatically. In this paper, a modular fuzzy neural network model for expert systems, based on a multilayer perceptron, is proposed. The model is capable of handling both the crisp and the fuzzy inputs, and the output of which is the inferred satisfactory solution. The effectiveness of the model is tested on the telecommunication network management control problem. The model is suitable for designing classification-type expert systems in which the domain knowledge may be a poor combination of knowledge from different experts.