The AMT1 Arginine Methyltransferase Gene Is Important for Plant Infection and Normal Hyphal Growth in Fusarium graminearum

Arginine methylation of non-histone proteins by protein arginine methyltransferase (PRMT) has been shown to be important for various biological processes from yeast to human. Although PRMT genes are well conserved in fungi, none of them have been functionally characterized in plant pathogenic ascomycetes. In this study, we identified and characterized all of the four predicted PRMT genes in Fusarium graminearum, the causal agent of Fusarium head blight of wheat and barley. Whereas deletion of the other three PRMT genes had no obvious phenotypes, the Δamt1 mutant had pleiotropic defects. AMT1 is a predicted type I PRMT gene that is orthologous to HMT1 in Saccharomyces cerevisiae. The Δamt1 mutant was slightly reduced in vegetative growth but normal in asexual and sexual reproduction. It had increased sensitivities to oxidative and membrane stresses. DON mycotoxin production and virulence on flowering wheat heads also were reduced in the Δamt1 mutant. The introduction of the wild-type AMT1 allele fully complemented the defects of the Δamt1 mutant and Amt1-GFP fusion proteins mainly localized to the nucleus. Hrp1 and Nab2 are two hnRNPs in yeast that are methylated by Hmt1 for nuclear export. In F. graminearum, AMT1 is required for the nuclear export of FgHrp1 but not FgNab2, indicating that yeast and F. graminearum differ in the methylation and nucleo-cytoplasmic transport of hnRNP components. Because AMT2 also is a predicted type I PRMT with limited homology to yeast HMT1, we generated the Δamt1 Δamt2 double mutants. The Δamt1 single and Δamt1 Δamt2 double mutants had similar defects in all the phenotypes assayed, including reduced vegetative growth and virulence. Overall, data from this systematic analysis of PRMT genes suggest that AMT1, like its ortholog in yeast, is the predominant PRMT gene in F. graminearum and plays a role in hyphal growth, stress responses, and plant infection

Cultural antecedents of sustainability and regional economic development - a study of SME ‘Mittelstand’ firms in Baden-Württemberg (Germany)

This paper examines behavioural and regional/geographic cultural antecedents of sustainability in SME contexts. The study identifies prevailing macro-representations of sustainability in the literature and highlights an over-focus on large firms constituting the predominant unit of analysis. Moreover, there is a propensity in the literature to view sustainability primarily in terms of ‘environmental’ – closely linked to a corporate strategic imperative narrative of economic competitiveness and profitability. Overall, this perspective tends to generate accounts which are acultural, apolitical and ahistorical in terms of innovative actions and sustainability practices. In response, using a conceptual framework of moral identity, the paper develops a more micro-foundational insight to sustainability (developing notions of ‘tangible’ and ‘intangible’) and examines regional economic development attitudes at individual owner-manager/managing director level in small-to-medium-sized firms. Methodologically, an inductively framed interview schedule was employed with owner-managers and managing directors (n = 30) of manufacturing SMEs in the Baden-Württemberg region (Germany). The study identified a range of micro-foundational behavioural antecedents operating in the sample companies. In particular, it underlined that many of the SME owner-managers/managing directors expressed views informed by a particular moral identity connected with a perspective rooted in regionally bound, longstanding and ‘expected’ behaviours of trust, fairness, honesty and community responsibility