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The global wheat disease tan spot is caused by the necrotrophic fungal pathogen Pyrenophora tritici‐repentis (Ptr) which secretes necrotrophic effectors to facilitate host plant colonization. We previously reported a role of the Zn2Cys6 binuclear cluster transcription factor Pf2 in the regulation of the Ptr effector ToxA. Here, we show that Pf2 is also a positive regulator of ToxB, via targeted deletion of PtrPf2 which resulted in reduced ToxB expression and defects in conidiation and pathogenicity. To further investigate the function of Ptr Pf2 in regulating protein secretion, the secretome profiles of two Δptrpf2 mutants of two Ptr races (races 1 and 5) were evaluated using a SWATH‐mass spectrometry (MS) quantitative approach. Analysis of the secretomes of the Δptrpf2 mutants from in vitro culture filtrate identified more than 500 secreted proteins, with 25% unique to each race. Of the identified proteins, less than 6% were significantly differentially regulated by Ptr Pf2. Among the downregulated proteins were ToxA and ToxB, specific to race 1 and race 5 respectively, demonstrating the role of Ptr Pf2 as a positive regulator of both effectors. Significant motif sequences identified in both ToxA and ToxB putative promoter regions were further explored via GFP reporter assays. [ABSTRACT FROM AUTHOR]

Recently the popular Private Finance Initiatives (PFI) was reformed into what is now known as Private Finance 2 (PF2). The move came against the backdrop of the unpleasant experiences which have bedeviled the PFI model leading to huge public sector bail-out and in some cases expensive buy-back schemes. One of the Principal areas being reformed is the financing structure which has often had a large portion of bank debt. The cost of capital on this significant portion of bank debt, studies have shown, has been responsible for the higher capital costs on past PFI projects. The proposed ideal financing structure for PF2 must be low cost funds such as pension funds and insurance funds. While this paper does not go into detail on how to structure a PF2 project using Islamic finance, it however argues that Islamic project finance holds a better promise for the financing of future PF2 projects. This is because apart from being interest-free, it also entails the sharing of losses should they occur, an act conventional project financiers are highly averse to doing. [ABSTRACT FROM AUTHOR]

Amylases are an important family of enzymes involved in insect carbohydrate metabolism that are required for the survival of insect larvae. For this reason, enzymes from starch-dependent insects are targets for insecticidal control. PF2 (Olneya tesota) is a lectin that is toxic to Zabrotes subfasciatus (Coleoptera: Bruchidae) larvae. In this study, we evaluated recognition of the PF2 lectin to α-amylases from Z. subfasciatus midgut and the effect of PF2 on α-amylase activity. PF2 caused a decrease of total amylase activity in vitro. Subsequently, several α-amylase isoforms were isolated from insect midgut tissues using ion exchange chromatography. Three enzyme isoforms were verified by an in-gel assay for amylase activity; however, only one isoform was recognized by antiamylase serum and PF2. The identity of this Z. subfasciatus α-amylase was confirmed by liquid chromatography−tandem mass spectrometry. The findings strongly suggest that a glycosylated α-amylase isoform from larval Z. subfasciatus midgut interacts with PF2, which interferes with starch digestion. [ABSTRACT FROM AUTHOR]

Abstract: WNK1 [with no lysine (K)-1] is a 250-kDa serine/threonine protein kinase involved in the maintenance of cellular salt levels and is directly linked to a hereditary form of hypertension. Here, we report the solution NMR structure of the autoinhibitory domain of WNK1 (WNK1-AI), a small regulatory subunit that lies immediately C-terminal of the kinase domain. We show that this domain is a homolog of the RFXV-binding PASK/FRAY homology 2 (PF2) domain found in OSR (oxidative stress responsive) and SPAK (serine/threonine proline–alanine-rich) kinases, which are substrates of WNK1. The WNK1-AI has a circularly permuted topology relative to the OSR1–PF2 domain. Nevertheless, like PF2 domains, WNK1-AI binds peptides that contain an RFXV motif with micromolar affinities as assessed by changes in 1H,15N heteronuclear single quantum coherence spectra. Mutations to the WNK1-AI and binding peptides confirm a similar binding mode. [Copyright &y& Elsevier]

The k-out-of-n structure is a very popular type of redundancy in fault-tolerant systems, it has founded wide applications in industrial and military systems during the past several decades. This paper will investigate the residual life length of a k-out-of-n system with independent (not necessarily identical) components, given that the (n-k)th failure has occurred at time t⩾0. Behaviour of PF2, IFR, DRHR, DMRL, NBU(2) and NBUC classes of life distributions are derived in terms of the monotonicity of the residual life given the time of the (n-k)th failure. Copyright © 2004 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Cryo-electron tomography (cryo-ET) has reached nanoscale resolution for in situ three-dimensional imaging of macromolecular complexes and organelles. Yet its current resolution is not sufficient to precisely localize or identify most proteins in situ; for example, the location and arrangement of components of the nexin-dynein regulatory complex (N-DRC), a key regulator of ciliary/flagellar motility that is conserved from algae to humans, have remained elusive despite many cryo-ET studies of cilia and flagella. Here, we developed an in situ localization method that combines cryo-ET/subtomogram averaging with the clonable SNAP tag, a widely used cell biological probe to visualize fusion proteins by fluorescence microscopy. Using this hybrid approach, we precisely determined the locations of the N and C termini of DRC3 and the C terminus of DRC4 within the three-dimensional structure of the N-DRC in Chlamydomonas flagella. Our data demonstrate that fusion of SNAP with target proteins allowed for protein localization with high efficiency and fidelity using SNAP-linked gold nanoparticles, without disrupting the native assembly, structure, or function of the flagella. After cryo-ET and subtomogram averaging, we localized DRC3 to the L1 projection of the nexin linker, which interacts directly with a dynein motor, whereas DRC4 was observed to stretch along the N-DRC base plate to the nexin linker. Application of the technique developed here to the N-DRC revealed new insights into the organization and regulatory mechanism of this complex, and provides a valuable tool for the structural dissection of macromolecular complexes in situ., (© 2015 by The American Society for Biochemistry and Molecular Biology, Inc.)