The Experts below are selected from a list of 1440 Experts worldwide ranked by ideXlab platform

Peter P Ueng - One of the best experts on this subject based on the ideXlab platform.

  • Group I introns in small subunit ribosomal DNA (SSUrDNA) of cereal Phaeosphaeria species
    台北市：中央研究院植物暨微生物學研究所, 2012
    Co-Authors: Chih-li Wang, A. Malkus, Pi-fang Linda Chang, Ling-yan Gao, Ying-hong Lin, Peter P Ueng
    Abstract:

    In a study of small Subunit ribosomal RNA (SSU-rRNA) gene sequences in cereal and a grass Phaeosphaeria species, group I introns were found in 9 of 10 P. avenaria f. sp. avenaria (Paa) isolates from oat (Avena saliva L.), I of 2 Phaeosphaeria sp. (P-rye) isolates (Sn48-1) from Polish rye (Secale cereale L.), I Phaeosphaeria sp. (P-dg) isolate (S-93-48) from dallis grass (Paspalum dilatatum Poir.) and both heterothallic P a. f. sp. triticea (Pat2) isolates (ATCC26370 and ATCC26377) from foxtail barley (Hordeum jubatum L.). There were no group I introns in wheat- and barley-biotype P. nodorum (PN-w and PN-b), homothallic P a. f. sp. triticea (Patl) and P a. f. sp. triticea (Pat3) from the state of Washington. Based on the reference 16S rDNA nucleotide sequence of Escherichia coli (accession number J01695), the intron-inserted positions of Pav.nS943, Pse.nS943, Ppa.nS1199 and Pho.nS1533 were determined to be at nt943, nt943, nt1199 and nt1533, respectively. The sizes of the introns were 362 bp for Pav.nS943 (from Paa), 363 bp for Pse.nS943 (from P-rye), 460 bp for Pho.nS1533 (from Pat2) and 383 bp for Ppa.nS1199 (P-dg). The intron-inserted position at nt1533 found in SSU-rRNA of Pat2 pathogen was newly discovered. The phylogenetic relationships based on aligned conserved secondary structure component sequences of group I introns showed that three introns from cereal Phaeosphaeria species (Pav.nS943, Pse.nS943 and Pho.nS1533) were likely affiliated with subgroup IC1 introns while Ppa.nS1199 intron from the dallis grass pathogen belonged to Subgroup IE3

  • Diversity of the trifunctional histidine biosynthesis gene (his) in cereal Phaeosphaeria species
    'Canadian Science Publishing', 2012
    Co-Authors: Chih-li Wang, Barry M. Cunfer, E Arseniuk, A. Malkus, Pi-fang Linda Chang, Sabina M Zuzga, Peter P Ueng
    Abstract:

    Phaeosphaeria species are important causal agents of Stagonospora leaf blotch diseases in cereals. In this study, the nucleotide sequence and deduced polypeptide of the trifunctional histidine biosynthesis gene (his) are used to investigate the phylogenetic relationships and provide molecular identification among cereal Phaeosphaeria species. The full-length sequences of the his gene were obtained by PCR amplification and compared among cereal Phaeosphaeria species. The coding sequence of the his gene in wheat-biotype P. nodorum (PN-w) was 2697 bp. The his genes in barley-biotype P. nodorum (PN-b), two P. avenaria f. sp. triticea isolates (homothallic Pat1 and Pat3), and Phaeosphaeria species from Polish rye and dallis grass were 2694 bp. The his gene in heterothallic isolate Pat2, however, was 2693 bp because the intron had one fewer base. In P. avenaria f. sp. avenaria (Paa), the his gene was only 2670 bp long. The differences in the size of the his gene contributed to the variation in amino acid sequences in the gap region located between the phosphoribosyl-ATP pyrophosphohydrolase and histidinol dehydrogenase sub-domains. Based on nucleotide and deduced amino acid sequences of the his gene, Pat1 was not closely related to either PN-w or the Paa clade. It appears that rates of evolution of the his gene were fast in cereal Phaeosphaeria species. The possible involvement of meiotic recombination in genetic diversity of the his gene in P. nodorum is discussed

  • Alternative splicing and genetic diversity of the white collar-1 (wc-1) gene in cereal Phaeosphaeria pathogens
    European Journal of Plant Pathology, 2010
    Co-Authors: Ericka Yen-hsin Chiu, Pi-fang Linda Chang, Ling-yan Gao, Chun-chi Chou, Ying-hong Lin, Qijian Song, Peter P Ueng
    Abstract:

    The white collar-1 (wc-1) gene encodes an important light-responsive protein (wc-1) that maintains circadian clocks and controls numerous light-dependent reactions including sporulation in ascomycete fungi. The structure and expression of the wc-1 gene in wheat-biotype Phaeosphaeria nodorum (PN-w) was studied. It was shown that the full-size (3,353 bp in length) wc-1 gene in PN-w contained 4 introns in which introns 1 and 2 were flanked by GC-AG splice borders and were spliced constitutively. However, introns 3 and 4 of the wc-1 gene were alternatively spliced. As the result of alternative splicing (AS), six transcript variants were identified, encoding different lengths of deduced polypeptides (from 1,044 to 1,065aa). Ratios of the wc-1 gene transcript variants in the RNA population were the same in the sporulated and non-sporulated PN-w isolate Sn37-1 and the sporulated PN-w isolate S-79-1, grown under light/dark conditions. The AS of the wc-1 gene may control various light-dependent reactions in PN-w, which leads to diverse morphological, physiological and pathological characters for pathogen infection and spread. Based on the nucleotide and deduced amino acid sequences, the wc-1 gene in cereal Phaeosphaeria pathogens was diverse. It appeared that the deduced wc-1 polypeptide sequences of P. avenaria f. sp. avenaria (Paa), P. avenaria f. sp. triticea (Pat1 and Pat3) and barley biotype P. nodorum (PN-b) were more closely related than PN-w and Phaeosphaeeria sp. (P-rye) from Poland. Based on the wc-1 deduced polypeptide sequences, P. avenaria f. sp. triticea (Pat2) from foxtail barley (Hordeum jubatum L.) was evolutionary well separated from the other cereal Phaeosphaeria pathogens

  • Genetic diversity of the white collar-2 (wc-2) gene in cereal Phaeosphaeria pathogens.
    Plant Pathology Bulletin, 2009
    Co-Authors: Ericka Yan-hsin Chiu, Pi-fang Linda Chang, Ling-yan Gao, Chun-chi Chou, Peter P Ueng
    Abstract:

    The white collar-2 (wc-2) gene encodes a light responsive white collar-2 (wc-2) protein that forms a heterodimeric complex with white collar-1 protein, activates numerous light-dependent reactions including asexual sporulation and pathogenic aggressiveness, and maintains circadian clocks in ascomycete fungi. The structure of the wc-2 gene and phylogenetic relationships based on the deduced polypeptide sequences in cereal Phaeosphacria pathogens were investigated. The wc-2 gene in 2 Phaeosphaeria nodorum (barley- (PN-b) and wheat- (PN-w) biotypes), 4 Phaeosphaeria avenaria (1 P. a. f. sp. avenaria, Paa and 3 P. a. f. sp. triticea, Pat1, Pat2 and Pat3), 1 Phaeosphaeria sp. from Polish rye (P-rye) and 1 Phaeosphaeria sp. from dallis grass (P-dg) contained two introns, transcribed to produce 1, 410 bp mRNA and encoded a 469 amino acid polypeptide. Based on the deduced polypeptide sequences, Phaeosphaeria species were phylogetically closely related as a group, with the exception of Pat2 isolates from wild foxtail barley (Hordeum jubatum L.).

  • Diversity of the trifunctional histidine biosynthesis gene (his) in cereal Phaeosphaeria species.
    Genome, 2007
    Co-Authors: Chih-li Wangc.-l. Wang, Barry M. Cunfer, E Arseniuk, A. Malkus, Sabina M Zuzga, Pi-fang Linda Changp.-f.l. Chang, Peter P Ueng
    Abstract:

    Phaeosphaeria species are important causal agents of Stagonospora leaf blotch diseases in cereals. In this study, the nucleotide sequence and deduced polypeptide of the trifunctional histidine biosynthesis gene (his) are used to investigate the phylogenetic relationships and provide molecular identification among cereal Phaeosphaeria species. The full-length sequences of the his gene were obtained by PCR amplification and compared among cereal Phaeosphaeria species. The coding sequence of the his gene in wheat-biotype P. nodorum (PN-w) was 2697 bp. The his genes in barley-biotype P. nodorum (PN-b), two P. avenaria f. sp. triticea isolates (homothallic Pat1 and Pat3), and Phaeosphaeria species from Polish rye and dallis grass were 2694 bp. The his gene in heterothallic isolate Pat2, however, was 2693 bp because the intron had one fewer base. In P. avenaria f. sp. avenaria (Paa), the his gene was only 2670 bp long. The differences in the size of the his gene contributed to the variation in amino acid sequen...

A. Malkus - One of the best experts on this subject based on the ideXlab platform.

  • Group I introns in small subunit ribosomal DNA (SSUrDNA) of cereal Phaeosphaeria species
    台北市：中央研究院植物暨微生物學研究所, 2012
    Co-Authors: Chih-li Wang, A. Malkus, Pi-fang Linda Chang, Ling-yan Gao, Ying-hong Lin, Peter P Ueng
    Abstract:

    In a study of small Subunit ribosomal RNA (SSU-rRNA) gene sequences in cereal and a grass Phaeosphaeria species, group I introns were found in 9 of 10 P. avenaria f. sp. avenaria (Paa) isolates from oat (Avena saliva L.), I of 2 Phaeosphaeria sp. (P-rye) isolates (Sn48-1) from Polish rye (Secale cereale L.), I Phaeosphaeria sp. (P-dg) isolate (S-93-48) from dallis grass (Paspalum dilatatum Poir.) and both heterothallic P a. f. sp. triticea (Pat2) isolates (ATCC26370 and ATCC26377) from foxtail barley (Hordeum jubatum L.). There were no group I introns in wheat- and barley-biotype P. nodorum (PN-w and PN-b), homothallic P a. f. sp. triticea (Patl) and P a. f. sp. triticea (Pat3) from the state of Washington. Based on the reference 16S rDNA nucleotide sequence of Escherichia coli (accession number J01695), the intron-inserted positions of Pav.nS943, Pse.nS943, Ppa.nS1199 and Pho.nS1533 were determined to be at nt943, nt943, nt1199 and nt1533, respectively. The sizes of the introns were 362 bp for Pav.nS943 (from Paa), 363 bp for Pse.nS943 (from P-rye), 460 bp for Pho.nS1533 (from Pat2) and 383 bp for Ppa.nS1199 (P-dg). The intron-inserted position at nt1533 found in SSU-rRNA of Pat2 pathogen was newly discovered. The phylogenetic relationships based on aligned conserved secondary structure component sequences of group I introns showed that three introns from cereal Phaeosphaeria species (Pav.nS943, Pse.nS943 and Pho.nS1533) were likely affiliated with subgroup IC1 introns while Ppa.nS1199 intron from the dallis grass pathogen belonged to Subgroup IE3

  • Diversity of the trifunctional histidine biosynthesis gene (his) in cereal Phaeosphaeria species
    'Canadian Science Publishing', 2012
    Co-Authors: Chih-li Wang, Barry M. Cunfer, E Arseniuk, A. Malkus, Pi-fang Linda Chang, Sabina M Zuzga, Peter P Ueng
    Abstract:

    Phaeosphaeria species are important causal agents of Stagonospora leaf blotch diseases in cereals. In this study, the nucleotide sequence and deduced polypeptide of the trifunctional histidine biosynthesis gene (his) are used to investigate the phylogenetic relationships and provide molecular identification among cereal Phaeosphaeria species. The full-length sequences of the his gene were obtained by PCR amplification and compared among cereal Phaeosphaeria species. The coding sequence of the his gene in wheat-biotype P. nodorum (PN-w) was 2697 bp. The his genes in barley-biotype P. nodorum (PN-b), two P. avenaria f. sp. triticea isolates (homothallic Pat1 and Pat3), and Phaeosphaeria species from Polish rye and dallis grass were 2694 bp. The his gene in heterothallic isolate Pat2, however, was 2693 bp because the intron had one fewer base. In P. avenaria f. sp. avenaria (Paa), the his gene was only 2670 bp long. The differences in the size of the his gene contributed to the variation in amino acid sequences in the gap region located between the phosphoribosyl-ATP pyrophosphohydrolase and histidinol dehydrogenase sub-domains. Based on nucleotide and deduced amino acid sequences of the his gene, Pat1 was not closely related to either PN-w or the Paa clade. It appears that rates of evolution of the his gene were fast in cereal Phaeosphaeria species. The possible involvement of meiotic recombination in genetic diversity of the his gene in P. nodorum is discussed

  • Diversity of the trifunctional histidine biosynthesis gene (his) in cereal Phaeosphaeria species.
    Genome, 2007
    Co-Authors: Chih-li Wangc.-l. Wang, Barry M. Cunfer, E Arseniuk, A. Malkus, Sabina M Zuzga, Pi-fang Linda Changp.-f.l. Chang, Peter P Ueng
    Abstract:

    Phaeosphaeria species are important causal agents of Stagonospora leaf blotch diseases in cereals. In this study, the nucleotide sequence and deduced polypeptide of the trifunctional histidine biosynthesis gene (his) are used to investigate the phylogenetic relationships and provide molecular identification among cereal Phaeosphaeria species. The full-length sequences of the his gene were obtained by PCR amplification and compared among cereal Phaeosphaeria species. The coding sequence of the his gene in wheat-biotype P. nodorum (PN-w) was 2697 bp. The his genes in barley-biotype P. nodorum (PN-b), two P. avenaria f. sp. triticea isolates (homothallic Pat1 and Pat3), and Phaeosphaeria species from Polish rye and dallis grass were 2694 bp. The his gene in heterothallic isolate Pat2, however, was 2693 bp because the intron had one fewer base. In P. avenaria f. sp. avenaria (Paa), the his gene was only 2670 bp long. The differences in the size of the his gene contributed to the variation in amino acid sequen...

  • RNA polymerase II gene (RPB2) encoding the second largest protein subunit in Phaeosphaeria nodorum and P. avenaria.
    Mycological research, 2006
    Co-Authors: A. Malkus, Kuangren Chung, Barry M. Cunfer, E Arseniuk, Pi-fang Linda Chang, Sabina M Zuzga, Jonathan Shao, Peter P Ueng
    Abstract:

    A 5586 bp sequence (accession no. DQ278491), which includes the RNA polymerase II gene (RPB2) encoding the second largest protein subunit (RPB2), was obtained from the wheat biotype Phaeosphaeria nodorum (PN-w) by PCR amplification. The 3841 bp full length RPB2 gene contains two exons and a 52 bp intron, and encodes a complete 1262 amino acid protein. Similar to the C-terminals of the beta subunits of prokaryotes and yeast RNA polymerases, the deduced RPB2 protein contained many structural features needed for gene transcription. Based on the phylogenetic analysis with the deduced RPB2 polypeptide sequences, the PN-w was closely related to the maize pathogen Cochliobolus heterostrophus. Size differences were found in the full length RPB2 gene of cereal Phaeosphaeria species, mainly due to differences in intron size. No nucleotide substitutions were found in homothallic P. avenaria f.sp. triticea (Pat1) and barley biotype P. nodorum (PN-b) isolates used in this study. The nucleotide and deduced amino acid sequences of the RPB2 gene in Pat1 were closely related to that in PN-w.

  • RNA polymerase II gene (RPB2) encoding the second largest protein subunit in Phaeosphaeria nodorum and P. avenaria
    Mycological Research, 2006
    Co-Authors: A. Malkus, Kuangren Chung, Barry M. Cunfer, E Arseniuk, Pi-fang Linda Chang, Sabina M Zuzga, Jonathan Shao, Peter P Ueng
    Abstract:

    A 5586 bp sequence (accession no. DQ278491), which includes the RNA polymerase II gene (RPB2) encoding the second largest protein subunit (RPB2), was obtained from the wheat biotype Phaeosphaeria nodorum (PN-w) by PCR amplification. The 3841 bp full length RPB2 gene contains two exons and a 52 bp intron, and encodes a complete 1262 amino acid protein. Similar to the C-terminals of the beta subunits of prokaryotes and yeast RNA polymerases, the deduced RPB2 protein contained many structural features needed for gene transcription. Based on the phylogenetic analysis with the deduced RPB2 polypeptide sequences, the PN-w was closely related to the maize pathogen Cochliobolus heterostrophus. Size differences were found in the full length RPB2 gene of cereal Phaeosphaeria species, mainly due to differences in intron size. No nucleotide substitutions were found in homothallic P. avenaria f.sp. triticea (Pat1) and barley biotype P. nodorum (PN-b) isolates used in this study. The nucleotide and deduced amino acid sequences of the RPB2 gene in Pat1 were closely related to that in PN-w. (c) 2006 The British Mycological Society. Published by Elsevier Ltd. All rights reserved

E Arseniuk - One of the best experts on this subject based on the ideXlab platform.

  • Diversity of the trifunctional histidine biosynthesis gene (his) in cereal Phaeosphaeria species
    'Canadian Science Publishing', 2012
    Co-Authors: Chih-li Wang, Barry M. Cunfer, E Arseniuk, A. Malkus, Pi-fang Linda Chang, Sabina M Zuzga, Peter P Ueng
    Abstract:

    Phaeosphaeria species are important causal agents of Stagonospora leaf blotch diseases in cereals. In this study, the nucleotide sequence and deduced polypeptide of the trifunctional histidine biosynthesis gene (his) are used to investigate the phylogenetic relationships and provide molecular identification among cereal Phaeosphaeria species. The full-length sequences of the his gene were obtained by PCR amplification and compared among cereal Phaeosphaeria species. The coding sequence of the his gene in wheat-biotype P. nodorum (PN-w) was 2697 bp. The his genes in barley-biotype P. nodorum (PN-b), two P. avenaria f. sp. triticea isolates (homothallic Pat1 and Pat3), and Phaeosphaeria species from Polish rye and dallis grass were 2694 bp. The his gene in heterothallic isolate Pat2, however, was 2693 bp because the intron had one fewer base. In P. avenaria f. sp. avenaria (Paa), the his gene was only 2670 bp long. The differences in the size of the his gene contributed to the variation in amino acid sequences in the gap region located between the phosphoribosyl-ATP pyrophosphohydrolase and histidinol dehydrogenase sub-domains. Based on nucleotide and deduced amino acid sequences of the his gene, Pat1 was not closely related to either PN-w or the Paa clade. It appears that rates of evolution of the his gene were fast in cereal Phaeosphaeria species. The possible involvement of meiotic recombination in genetic diversity of the his gene in P. nodorum is discussed

  • Diversity of the trifunctional histidine biosynthesis gene (his) in cereal Phaeosphaeria species.
    Genome, 2007
    Co-Authors: Chih-li Wangc.-l. Wang, Barry M. Cunfer, E Arseniuk, A. Malkus, Sabina M Zuzga, Pi-fang Linda Changp.-f.l. Chang, Peter P Ueng
    Abstract:

    Phaeosphaeria species are important causal agents of Stagonospora leaf blotch diseases in cereals. In this study, the nucleotide sequence and deduced polypeptide of the trifunctional histidine biosynthesis gene (his) are used to investigate the phylogenetic relationships and provide molecular identification among cereal Phaeosphaeria species. The full-length sequences of the his gene were obtained by PCR amplification and compared among cereal Phaeosphaeria species. The coding sequence of the his gene in wheat-biotype P. nodorum (PN-w) was 2697 bp. The his genes in barley-biotype P. nodorum (PN-b), two P. avenaria f. sp. triticea isolates (homothallic Pat1 and Pat3), and Phaeosphaeria species from Polish rye and dallis grass were 2694 bp. The his gene in heterothallic isolate Pat2, however, was 2693 bp because the intron had one fewer base. In P. avenaria f. sp. avenaria (Paa), the his gene was only 2670 bp long. The differences in the size of the his gene contributed to the variation in amino acid sequen...

  • RNA polymerase II gene (RPB2) encoding the second largest protein subunit in Phaeosphaeria nodorum and P. avenaria.
    Mycological research, 2006
    Co-Authors: A. Malkus, Kuangren Chung, Barry M. Cunfer, E Arseniuk, Pi-fang Linda Chang, Sabina M Zuzga, Jonathan Shao, Peter P Ueng
    Abstract:

    A 5586 bp sequence (accession no. DQ278491), which includes the RNA polymerase II gene (RPB2) encoding the second largest protein subunit (RPB2), was obtained from the wheat biotype Phaeosphaeria nodorum (PN-w) by PCR amplification. The 3841 bp full length RPB2 gene contains two exons and a 52 bp intron, and encodes a complete 1262 amino acid protein. Similar to the C-terminals of the beta subunits of prokaryotes and yeast RNA polymerases, the deduced RPB2 protein contained many structural features needed for gene transcription. Based on the phylogenetic analysis with the deduced RPB2 polypeptide sequences, the PN-w was closely related to the maize pathogen Cochliobolus heterostrophus. Size differences were found in the full length RPB2 gene of cereal Phaeosphaeria species, mainly due to differences in intron size. No nucleotide substitutions were found in homothallic P. avenaria f.sp. triticea (Pat1) and barley biotype P. nodorum (PN-b) isolates used in this study. The nucleotide and deduced amino acid sequences of the RPB2 gene in Pat1 were closely related to that in PN-w.

  • RNA polymerase II gene (RPB2) encoding the second largest protein subunit in Phaeosphaeria nodorum and P. avenaria
    Mycological Research, 2006
    Co-Authors: A. Malkus, Kuangren Chung, Barry M. Cunfer, E Arseniuk, Pi-fang Linda Chang, Sabina M Zuzga, Jonathan Shao, Peter P Ueng
    Abstract:

    A 5586 bp sequence (accession no. DQ278491), which includes the RNA polymerase II gene (RPB2) encoding the second largest protein subunit (RPB2), was obtained from the wheat biotype Phaeosphaeria nodorum (PN-w) by PCR amplification. The 3841 bp full length RPB2 gene contains two exons and a 52 bp intron, and encodes a complete 1262 amino acid protein. Similar to the C-terminals of the beta subunits of prokaryotes and yeast RNA polymerases, the deduced RPB2 protein contained many structural features needed for gene transcription. Based on the phylogenetic analysis with the deduced RPB2 polypeptide sequences, the PN-w was closely related to the maize pathogen Cochliobolus heterostrophus. Size differences were found in the full length RPB2 gene of cereal Phaeosphaeria species, mainly due to differences in intron size. No nucleotide substitutions were found in homothallic P. avenaria f.sp. triticea (Pat1) and barley biotype P. nodorum (PN-b) isolates used in this study. The nucleotide and deduced amino acid sequences of the RPB2 gene in Pat1 were closely related to that in PN-w. (c) 2006 The British Mycological Society. Published by Elsevier Ltd. All rights reserved

  • A New Biotype of Phaeosphaeria sp. of Uncertain Affinity Causing Stagonospora Leaf Blotch Disease in Cereals in Poland
    Plant disease, 2006
    Co-Authors: E. Reszka, Kuangren Chung, E Arseniuk, A. Malkus, Qijian Song, Nichole R. O'neill, P P Ueng
    Abstract:

    A new Phaeosphaeria sp. biotype was isolated from winter ryes in Poland during 1995. Two isolates, Sn23-1 and Sn48-1, were obtained from diseased leaves of cvs. Motto and Dańkowskie, respectively. The rye Phaeosphaeria sp. represented by isolate Sn48-1 has similar pycnidiospore morphology and induces disease symptoms in cereals similar to Phaeosphaeria nodorum, the causal agent of Stagonospora nodorum blotch disease (4). The pathogen (Sn48-1) produces hyaline, cylindrical pycnidiospores that are mostly three-septate and measure 12.8 to 23.7 × 2.1 to 3.2 μm (average size = 16 × 2.6 μm) on water agar. A molecular comparison of several genes in isolates Sn23-1 and Sn48-1 revealed that the rye Phaeosphaeria sp. was different from P. nodorum. In the conserved alpha-box sequence (1,93 bp) of the MAT1-1 gene, a four nucleotide difference occurred between the wheat-biotype P. nodorum and isolates Sn23-1 and Sn48-1 (GenBank Accession Nos. AY072933 and AF322008). In addition, the length of the internal transcribed spacer (ITS) region of the nuclear rDNA was the same for the wheat-biotype P. nodorum and the two rye Phaeosphaeria sp. isolates. However, a six nucleotide discrepancy was found in the ITS region (GenBank Accession Nos. U77362 and AF321323). The beta-glucosidase (bgl1) and beta-tubulin (tubA) genes differ in length between the wheat-biotype P. nodorum and two rye Phaeosphaeria sp. isolates (2,3). The main difference was due to the intron sizes of these two genes. One extra nucleotide was found in the intron2 of the bgl1 gene (GenBank Accession Nos. AY683619 and AY683620) and the intron1 of the tubA gene (GenBank Accession Nos. AY786337 and AY786331), respectively, in these two rye Phaeosphaeria sp. isolates. Disease severity on the fifth leaf (GS15) of Polish wheat (Alba, Begra, and Liwilla), triticale (Bogo and Pinokio), and rye (Zduno) cultivars was assessed with one (resistant) to nine (susceptible) scales 14 days after inoculation. Aggressiveness of wheat-biotype P. nodorum isolate Sn26-1 and rye Phaeosphaeria sp. isolate Sn48-1 was significant (P < 0.01) in five cultivars except in the moderately resistant wheat cv. Liwilla. The rye Phaeosphaeria sp. isolate Sn48-1 severely affected Polish rye Zduno (8.3) and two triticale cultivars (6.5), while the infection by isolate Sn26-1 was moderate (3-4). On the contrary, the wheat-biotype P. nodorum isolate Sn26-1 was more aggressive on wheat (4.1 on moderately resistant Alba and 6.2 on highly susceptible Begra) than the rye Phaeosphaeria sp. isolate Sn48-1, which had a scale of 2.2 and 4.3, respectively. Under laboratory conditions, the rye isolate Sn48-1 was able to cross with the wheat-biotype P. nodorum isolate Sn26-1 that has an opposite mating-type (MAT1-2) gene, but few viable ascospores were produced (1). References: (1) P. C. Czembor and E. Arseniuk. Mycol. Res. 104:919, 2000. (2) A. Malkus et al. FEMS (Fed. Eur. Microbiol. Soc.) Lett. 249:49, 2005. (3) E. Reszka et al. Can. J. Bot. 83:1001, 2005. (4) M. J. Richardson and M. Noble. Plant Pathol. 19:159, 1970.

Pi-fang Linda Chang - One of the best experts on this subject based on the ideXlab platform.

  • Diversity of the trifunctional histidine biosynthesis gene (his) in cereal Phaeosphaeria species
    'Canadian Science Publishing', 2012
    Co-Authors: Chih-li Wang, Barry M. Cunfer, E Arseniuk, A. Malkus, Pi-fang Linda Chang, Sabina M Zuzga, Peter P Ueng
    Abstract:

    Phaeosphaeria species are important causal agents of Stagonospora leaf blotch diseases in cereals. In this study, the nucleotide sequence and deduced polypeptide of the trifunctional histidine biosynthesis gene (his) are used to investigate the phylogenetic relationships and provide molecular identification among cereal Phaeosphaeria species. The full-length sequences of the his gene were obtained by PCR amplification and compared among cereal Phaeosphaeria species. The coding sequence of the his gene in wheat-biotype P. nodorum (PN-w) was 2697 bp. The his genes in barley-biotype P. nodorum (PN-b), two P. avenaria f. sp. triticea isolates (homothallic Pat1 and Pat3), and Phaeosphaeria species from Polish rye and dallis grass were 2694 bp. The his gene in heterothallic isolate Pat2, however, was 2693 bp because the intron had one fewer base. In P. avenaria f. sp. avenaria (Paa), the his gene was only 2670 bp long. The differences in the size of the his gene contributed to the variation in amino acid sequences in the gap region located between the phosphoribosyl-ATP pyrophosphohydrolase and histidinol dehydrogenase sub-domains. Based on nucleotide and deduced amino acid sequences of the his gene, Pat1 was not closely related to either PN-w or the Paa clade. It appears that rates of evolution of the his gene were fast in cereal Phaeosphaeria species. The possible involvement of meiotic recombination in genetic diversity of the his gene in P. nodorum is discussed

  • Group I introns in small subunit ribosomal DNA (SSUrDNA) of cereal Phaeosphaeria species
    台北市：中央研究院植物暨微生物學研究所, 2012
    Co-Authors: Chih-li Wang, A. Malkus, Pi-fang Linda Chang, Ling-yan Gao, Ying-hong Lin, Peter P Ueng
    Abstract:

    In a study of small Subunit ribosomal RNA (SSU-rRNA) gene sequences in cereal and a grass Phaeosphaeria species, group I introns were found in 9 of 10 P. avenaria f. sp. avenaria (Paa) isolates from oat (Avena saliva L.), I of 2 Phaeosphaeria sp. (P-rye) isolates (Sn48-1) from Polish rye (Secale cereale L.), I Phaeosphaeria sp. (P-dg) isolate (S-93-48) from dallis grass (Paspalum dilatatum Poir.) and both heterothallic P a. f. sp. triticea (Pat2) isolates (ATCC26370 and ATCC26377) from foxtail barley (Hordeum jubatum L.). There were no group I introns in wheat- and barley-biotype P. nodorum (PN-w and PN-b), homothallic P a. f. sp. triticea (Patl) and P a. f. sp. triticea (Pat3) from the state of Washington. Based on the reference 16S rDNA nucleotide sequence of Escherichia coli (accession number J01695), the intron-inserted positions of Pav.nS943, Pse.nS943, Ppa.nS1199 and Pho.nS1533 were determined to be at nt943, nt943, nt1199 and nt1533, respectively. The sizes of the introns were 362 bp for Pav.nS943 (from Paa), 363 bp for Pse.nS943 (from P-rye), 460 bp for Pho.nS1533 (from Pat2) and 383 bp for Ppa.nS1199 (P-dg). The intron-inserted position at nt1533 found in SSU-rRNA of Pat2 pathogen was newly discovered. The phylogenetic relationships based on aligned conserved secondary structure component sequences of group I introns showed that three introns from cereal Phaeosphaeria species (Pav.nS943, Pse.nS943 and Pho.nS1533) were likely affiliated with subgroup IC1 introns while Ppa.nS1199 intron from the dallis grass pathogen belonged to Subgroup IE3

  • Alternative splicing and genetic diversity of the white collar-1 (wc-1) gene in cereal Phaeosphaeria pathogens
    European Journal of Plant Pathology, 2010
    Co-Authors: Ericka Yen-hsin Chiu, Pi-fang Linda Chang, Ling-yan Gao, Chun-chi Chou, Ying-hong Lin, Qijian Song, Peter P Ueng
    Abstract:

    The white collar-1 (wc-1) gene encodes an important light-responsive protein (wc-1) that maintains circadian clocks and controls numerous light-dependent reactions including sporulation in ascomycete fungi. The structure and expression of the wc-1 gene in wheat-biotype Phaeosphaeria nodorum (PN-w) was studied. It was shown that the full-size (3,353 bp in length) wc-1 gene in PN-w contained 4 introns in which introns 1 and 2 were flanked by GC-AG splice borders and were spliced constitutively. However, introns 3 and 4 of the wc-1 gene were alternatively spliced. As the result of alternative splicing (AS), six transcript variants were identified, encoding different lengths of deduced polypeptides (from 1,044 to 1,065aa). Ratios of the wc-1 gene transcript variants in the RNA population were the same in the sporulated and non-sporulated PN-w isolate Sn37-1 and the sporulated PN-w isolate S-79-1, grown under light/dark conditions. The AS of the wc-1 gene may control various light-dependent reactions in PN-w, which leads to diverse morphological, physiological and pathological characters for pathogen infection and spread. Based on the nucleotide and deduced amino acid sequences, the wc-1 gene in cereal Phaeosphaeria pathogens was diverse. It appeared that the deduced wc-1 polypeptide sequences of P. avenaria f. sp. avenaria (Paa), P. avenaria f. sp. triticea (Pat1 and Pat3) and barley biotype P. nodorum (PN-b) were more closely related than PN-w and Phaeosphaeeria sp. (P-rye) from Poland. Based on the wc-1 deduced polypeptide sequences, P. avenaria f. sp. triticea (Pat2) from foxtail barley (Hordeum jubatum L.) was evolutionary well separated from the other cereal Phaeosphaeria pathogens

  • Genetic diversity of the white collar-2 (wc-2) gene in cereal Phaeosphaeria pathogens.
    Plant Pathology Bulletin, 2009
    Co-Authors: Ericka Yan-hsin Chiu, Pi-fang Linda Chang, Ling-yan Gao, Chun-chi Chou, Peter P Ueng
    Abstract:

    The white collar-2 (wc-2) gene encodes a light responsive white collar-2 (wc-2) protein that forms a heterodimeric complex with white collar-1 protein, activates numerous light-dependent reactions including asexual sporulation and pathogenic aggressiveness, and maintains circadian clocks in ascomycete fungi. The structure of the wc-2 gene and phylogenetic relationships based on the deduced polypeptide sequences in cereal Phaeosphacria pathogens were investigated. The wc-2 gene in 2 Phaeosphaeria nodorum (barley- (PN-b) and wheat- (PN-w) biotypes), 4 Phaeosphaeria avenaria (1 P. a. f. sp. avenaria, Paa and 3 P. a. f. sp. triticea, Pat1, Pat2 and Pat3), 1 Phaeosphaeria sp. from Polish rye (P-rye) and 1 Phaeosphaeria sp. from dallis grass (P-dg) contained two introns, transcribed to produce 1, 410 bp mRNA and encoded a 469 amino acid polypeptide. Based on the deduced polypeptide sequences, Phaeosphaeria species were phylogetically closely related as a group, with the exception of Pat2 isolates from wild foxtail barley (Hordeum jubatum L.).

  • RNA polymerase II gene (RPB2) encoding the second largest protein subunit in Phaeosphaeria nodorum and P. avenaria.
    Mycological research, 2006
    Co-Authors: A. Malkus, Kuangren Chung, Barry M. Cunfer, E Arseniuk, Pi-fang Linda Chang, Sabina M Zuzga, Jonathan Shao, Peter P Ueng
    Abstract:

    A 5586 bp sequence (accession no. DQ278491), which includes the RNA polymerase II gene (RPB2) encoding the second largest protein subunit (RPB2), was obtained from the wheat biotype Phaeosphaeria nodorum (PN-w) by PCR amplification. The 3841 bp full length RPB2 gene contains two exons and a 52 bp intron, and encodes a complete 1262 amino acid protein. Similar to the C-terminals of the beta subunits of prokaryotes and yeast RNA polymerases, the deduced RPB2 protein contained many structural features needed for gene transcription. Based on the phylogenetic analysis with the deduced RPB2 polypeptide sequences, the PN-w was closely related to the maize pathogen Cochliobolus heterostrophus. Size differences were found in the full length RPB2 gene of cereal Phaeosphaeria species, mainly due to differences in intron size. No nucleotide substitutions were found in homothallic P. avenaria f.sp. triticea (Pat1) and barley biotype P. nodorum (PN-b) isolates used in this study. The nucleotide and deduced amino acid sequences of the RPB2 gene in Pat1 were closely related to that in PN-w.

E. Reszka - One of the best experts on this subject based on the ideXlab platform.

  • A New Biotype of Phaeosphaeria sp. of Uncertain Affinity Causing Stagonospora Leaf Blotch Disease in Cereals in Poland
    Plant disease, 2006
    Co-Authors: E. Reszka, Kuangren Chung, E Arseniuk, A. Malkus, Qijian Song, Nichole R. O'neill, P P Ueng
    Abstract:

    A new Phaeosphaeria sp. biotype was isolated from winter ryes in Poland during 1995. Two isolates, Sn23-1 and Sn48-1, were obtained from diseased leaves of cvs. Motto and Dańkowskie, respectively. The rye Phaeosphaeria sp. represented by isolate Sn48-1 has similar pycnidiospore morphology and induces disease symptoms in cereals similar to Phaeosphaeria nodorum, the causal agent of Stagonospora nodorum blotch disease (4). The pathogen (Sn48-1) produces hyaline, cylindrical pycnidiospores that are mostly three-septate and measure 12.8 to 23.7 × 2.1 to 3.2 μm (average size = 16 × 2.6 μm) on water agar. A molecular comparison of several genes in isolates Sn23-1 and Sn48-1 revealed that the rye Phaeosphaeria sp. was different from P. nodorum. In the conserved alpha-box sequence (1,93 bp) of the MAT1-1 gene, a four nucleotide difference occurred between the wheat-biotype P. nodorum and isolates Sn23-1 and Sn48-1 (GenBank Accession Nos. AY072933 and AF322008). In addition, the length of the internal transcribed spacer (ITS) region of the nuclear rDNA was the same for the wheat-biotype P. nodorum and the two rye Phaeosphaeria sp. isolates. However, a six nucleotide discrepancy was found in the ITS region (GenBank Accession Nos. U77362 and AF321323). The beta-glucosidase (bgl1) and beta-tubulin (tubA) genes differ in length between the wheat-biotype P. nodorum and two rye Phaeosphaeria sp. isolates (2,3). The main difference was due to the intron sizes of these two genes. One extra nucleotide was found in the intron2 of the bgl1 gene (GenBank Accession Nos. AY683619 and AY683620) and the intron1 of the tubA gene (GenBank Accession Nos. AY786337 and AY786331), respectively, in these two rye Phaeosphaeria sp. isolates. Disease severity on the fifth leaf (GS15) of Polish wheat (Alba, Begra, and Liwilla), triticale (Bogo and Pinokio), and rye (Zduno) cultivars was assessed with one (resistant) to nine (susceptible) scales 14 days after inoculation. Aggressiveness of wheat-biotype P. nodorum isolate Sn26-1 and rye Phaeosphaeria sp. isolate Sn48-1 was significant (P < 0.01) in five cultivars except in the moderately resistant wheat cv. Liwilla. The rye Phaeosphaeria sp. isolate Sn48-1 severely affected Polish rye Zduno (8.3) and two triticale cultivars (6.5), while the infection by isolate Sn26-1 was moderate (3-4). On the contrary, the wheat-biotype P. nodorum isolate Sn26-1 was more aggressive on wheat (4.1 on moderately resistant Alba and 6.2 on highly susceptible Begra) than the rye Phaeosphaeria sp. isolate Sn48-1, which had a scale of 2.2 and 4.3, respectively. Under laboratory conditions, the rye isolate Sn48-1 was able to cross with the wheat-biotype P. nodorum isolate Sn26-1 that has an opposite mating-type (MAT1-2) gene, but few viable ascospores were produced (1). References: (1) P. C. Czembor and E. Arseniuk. Mycol. Res. 104:919, 2000. (2) A. Malkus et al. FEMS (Fed. Eur. Microbiol. Soc.) Lett. 249:49, 2005. (3) E. Reszka et al. Can. J. Bot. 83:1001, 2005. (4) M. J. Richardson and M. Noble. Plant Pathol. 19:159, 1970.

  • Presence of β-glucosidase (bgl1) gene in Phaeosphaeria nodorum and Phaeosphaeria avenaria f.sp. triticea
    Canadian Journal of Botany, 2005
    Co-Authors: E. Reszka, Kuangren Chung, E Arseniuk, A Tekauz, A. Malkus, J M Krupinsky, H Tsang, P P Ueng
    Abstract:

    Phaeosphaeria avenaria f.sp. avenaria (Paa), the causal agent of stagonospora leaf blotch in oats, produces a glycosyl hydrolase family 3 enzyme, β-glucosidase, which is responsible for detoxification of steroidal avenacosides in oat leaves, but is not essential for pathogenicity. For a comparative genetic relatedness study, a Paa-like β-glucosidase gene (bgl1) was PCR-amplified from Phaeosphaeria nodorum and P. avenaria f.sp. triticea, and Phaeosphaeria spp. from dallis grass (Paspalum dilatatum) (isolate S-93-48) and rye (Secale cereale) (isolate Sn48-1). Different sizes of bgl1 gene coding sequences ranging from 3018 to 3023 bp were determined. The bgl1 gene structure in these Phaeosphaeria species was identical to that of Paa and contained four exons and three introns. Nucleotide variations occurring in introns 1 and 2 of the bgl1 gene divided wheat-biotype P. nodorum into four groups. Two 12-bp-long direct sequence repeats (5'-TCA/G ACT GGT TT/CA/G) were found in the promoter region of the bgl1 gene ...

  • Sequence diversity of β-tubulin (tubA) gene in Phaeosphaeria nodorum and P. avenaria
    FEMS microbiology letters, 2005
    Co-Authors: A. Malkus, Chungjan Chang, E Arseniuk, E. Reszka, Pi-fang Linda Chang, Peter P Ueng
    Abstract:

    Full-length coding sequences of the beta-tubulin gene (tubA) were PCR-amplified and sequenced from 42 Phaeosphaeria isolates, including 16 P. nodorum and 23 P. avenaria species from cereals, two Polish isolates from rye (Secale cereale L.), and one isolate from dallis grass (Paspalum dilatatum Poir). A tubA gene of size 1556bp was identified in wheat- and barley-biotype P. nodorum (PN-w and PN-b), P. avenaria f. sp. avenaria (Paa), homothallic P. avenaria f. sp. triticea (P.a.t.) (Pat1) and the P.a.t. isolate (Pat3) from the State of Washington. The tubA gene length polymorphisms were detected in two P.a.t. isolates (Pat2) from foxtail barley (Hordeum jubatum L.), one from dallis grass and two Polish isolates from rye. These size differences were due to the variation of intron lengths among these three Phaeosphaeria species. All Phaeosphaeria isolates have identical 1344bp exons that can be translated into a 447 amino acid beta-tubulin. Like glyceraldehyde-3-phosphate dehydrogenase, the beta-tubulin amino acid sequence was identical in all Phaeosphaeria species used in this study, with the exception of the two Pat2 isolates. Six amino acid differences were evident in the beta-tubulin of these Pat2 isolates.

  • sequence diversity of β tubulin tuba gene in Phaeosphaeria nodorum and p avenaria
    Fems Microbiology Letters, 2005
    Co-Authors: A. Malkus, Chungjan Chang, E Arseniuk, E. Reszka, Pi-fang Linda Chang, Peter P Ueng
    Abstract:

    Abstract Full-length coding sequences of the β-tubulin gene ( tubA ) were PCR-amplified and sequenced from 42 Phaeosphaeria isolates, including 16 P. nodorum and 23 P. avenaria species from cereals, two Polish isolates from rye ( Secale cereale L.), and one isolate from dallis grass ( Paspalum dilatatum Poir). A tubA gene of size 1556 bp was identified in wheat- and barley-biotype P. nodorum (PN-w and PN-b), P. avenaria f. sp. avenaria (Paa), homothallic P. avenaria f. sp. triticea ( P . a . t .) (Pat1) and the P . a . t . isolate (Pat3) from the State of Washington. The tubA gene length polymorphisms were detected in two P . a . t . isolates (Pat2) from foxtail barley ( Hordeum jubatum L.), one from dallis grass and two Polish isolates from rye. These size differences were due to the variation of intron lengths among these three Phaeosphaeria species. All Phaeosphaeria isolates have identical 1344 bp exons that can be translated into a 447 amino acid β-tubulin. Like glyceraldehyde-3-phosphate dehydrogenase, the β-tubulin amino acid sequence was identical in all Phaeosphaeria species used in this study, with the exception of the two Pat2 isolates. Six amino acid differences were evident in the β-tubulin of these Pat2 isolates.

  • comparison of glyceraldehyde 3 phosphate dehydrogenase genes in Phaeosphaeria nodorum and p avenaria species
    植物病理學會刊, 2003
    Co-Authors: P P Ueng, Kuangren Chung, E Arseniuk, E. Reszka, J M Krupinsky
    Abstract:

    Stagonospora leaf blotch of cereals is a complex disease caused by several Phaeosphaeria fungal species. Genetic diversity among glyceraldehydes-3-phosphate dehydrogenase (gpd) genes of Phaeosphaeria nodorum, P. avenaria f. sp. triticea (P.a.t.) and P. avenaria f. sp. avenaria (P.a.a.), three causal agents of stagonospora leaf blotch diseases in cereals, was evaluated in this study. The PCR-amplified gpd gene from these cereal Phaeosphaeria species contained 4 introns. The gpd gene in wheat-biotype P. nodorum isolates ranged in size from 1,253-1,255bp. Sequence variations in intron 4 were used to divide the wheat-biotype P. nodorum isolates into two subgroups. These two subgroups were equally represented in a survey of field wheat-biotype P. nodorum isolates. Except Pat2, the gpd genes in Patl and Pat3 of the P.a.t. group, the P.a.a. group and the barley-biotype P. nodorum were 1,251 bp in length and phylogenetically closely related. As the nucleotide changes in gpd genes occurred mostly in intron regions and the third codons of amino acid coding triplets, the deduced protein sequences in three cereal Phaeosphaeria species were identical, except for Pat2. The gpd-encoded protein in Pat2 isolates contained two amino acid substitutions. The deduced GPD proteins of three cereal Phaeosphaeria species are closely related to the GPD protein that has been described in a maize pathogen, Cochliobolus heterostrophus. Based on phylogenetic analysis, the possible evolution of these cereal Phaeosphaeria species in relation to other ascomycetes is discussed.