Tpc1 is an important Zn(II)(2)Cys(6) transcriptional regulator required for polarized growth and virulence in the rice blast fungus

The establishment of polarity is a critical process in pathogenic fungi, mediating infection-related morphogenesis and host tissue invasion. Here, we report the identification of TPC1 (Transcription factor for Polarity Control 1), which regulates invasive polarized growth in the rice blast fungus Magnaporthe oryzae. TPC1 encodes a putative transcription factor of the fungal Zn(II)(2)Cys(6) family, exclusive to filamentous fungi. Tpc1-deficient mutants show severe defects in conidiogenesis, infection-associated autophagy, glycogen and lipid metabolism, and plant tissue colonisation. By tracking actin-binding proteins, septin-5 and autophagosome components, we show that Tpc1 regulates cytoskeletal dynamics and infection-associated autophagy during appressorium-mediated plant penetration. We found that Tpc1 interacts with Mst12 and modulates its DNA-binding activity, while Tpc1 nuclear localisation also depends on the MAP kinase Pmk1, consistent with the involvement of Tpc1 in this signalling pathway, which is critical for appressorium development. Importantly, Tpc1 directly regulates NOXD expression, the p22(phox) subunit of the fungal NADPH oxidase complex via an interaction with Mst12. Tpc1 therefore controls spatial and temporal regulation of cortical F-actin through regulation of the NADPH oxidase complex during appressorium re-polarisation. Consequently, Tpc1 is a core developmental regulator in filamentous fungi, linking the regulated synthesis of reactive oxygen species and the Pmk1 pathway, with polarity control during host invasion

Not Available

Not AvailableTesting the genetic fidelity of micropropagated clones with DNA markers could curtail the losses caused by somaclonal variation in sugarcane tissue culture industry. Evaluation of 32 inter-retrotransposon amplified polymorphism (IRAP) markers and 100 inter-simple sequence repeats (ISSRs) in 47 sugarcane accessions identified 20 (8 IRAPs and 12 ISSRs) polymorphic markers representing 98 loci. IRAP system was superior to ISSR in terms of marker index (2.68 as against 1.76), resolving power (2.85 as against 1.98), and polymorphic loci per assay (6 compared to 4.1), except mean polymorphic information content (0.31 and 0.34). Further evaluation of the 20 polymorphic markers in testing the genetic fidelity of micropropagated sugarcane clones identified a variant clone by three primers of ISSR and one IRAP marker (UBC810, UBC813, UBC840, and LTR6149 + 3’LTR). The unique amplicons from the somaclonal variant were validated by sequencing. Based on the number of bands amplified and proportion of polymorphic loci, a set of six ISSR and four IRAP markers has been recommended to test clonal fidelity for sugarcane tissue culture industry.Not Availabl

Identification of novel alleles of the rice blast resistance gene Pi54

Rice blast is one of the most devastating rice diseases and continuous resistance breeding is required to control the disease. The rice blast resistance gene Pi54 initially identified in an Indian cultivar confers broad-spectrum resistance in India. We explored the allelic diversity of the Pi54 gene among 885 Indian rice genotypes that were found resistant in our screening against field mixture of naturally existing M. oryzae strains as well as against five unique strains. These genotypes are also annotated as rice blast resistant in the International Rice Genebank database. Sequence-based allele mining was used to amplify and clone the Pi54 allelic variants. Nine new alleles of Pi54 were identified based on the nucleotide sequence comparison to the Pi54 reference sequence as well as to already known Pi54 alleles. DNA sequence analysis of the newly identified Pi54 alleles revealed several single polymorphic sites, three double deletions and an eight base pair deletion. A SNP-rich region was found between a tyrosine kinase phosphorylation site and the nucleotide binding site (NBS) domain. Together, the newly identified Pi54 alleles expand the allelic series and are candidates for rice blast resistance breeding programs

Work–life programs and performance in Australian organisations: the role of organisation size and industry type

Organisations are increasingly using work–life programs to strategically manage their workforce in a competitive labour market. Extant research has investigated various outcomes of work–life programs but has lacked focus on organisational financial performance and context. Drawing on strategic human resource management theory, this study proposes and tests a work–life programs–performance relationship. It also investigates the moderating effects of organisation size and industry on the work–life programs–performance relationship. We used a time-lagged design and data from multiple sources to link work–life programs with firm performance in 117 organisations in Australia. The findings support the hypothesis that work–life programs are positively associated with financial performance. This study also provides pioneering evidence for the moderating effects of organisation size and industry type on the work–life programs–organisational performance relationship.</p