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Andreas M. Perlick - One of the best experts on this subject based on the ideXlab platform.
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the broad bean nodulin vfenod18 is a member of a novel family of plant proteins with homologies to the bacterial mj0577 superfamily
Molecular Genetics and Genomics, 2000Co-Authors: Natalija Hohnjec, U. Albus, Alfred Pühler, Andreas M. Perlick, Helge Küster, Jörg D. Becker, S C Frosch, Martin FrühlingAbstract:Full-length transcript sequences were isolated from broad bean root nodules, which encode a novel nodulin designated VfENOD18. The corresponding transcripts were detected in early and in late stages of nodule development and were localized exclusively in the nitrogen-fixing zone III. The VfENOD18 sequence is not only homologous to a number of ESTs from various mono- and dicotyledonous plants, but also to the ATP-binding protein MJ0577 from Methanococcus jannaschii and to a range of bacterial proteins that belong to the MJ0577 superfamily. Hence, VfENOD18 is a member of a ubiquitous family of plant proteins that might function as ATP-binding proteins or ATPases. On the genomic level, VfENOD18 genes can be divided into two groups on the basis of differences in their 5' UTRs. One group lacks the 5' UTR region including the ATG initiation codon, whereas the second group contained the complete 5' UTR region. Further upstream of this VfENOD18 gene, a retrotransposon sequence was identified. The -14/-964 VfENOD18 promoter fragment was devoid of complete organ-specific elements known from other nodulin gene promoters. Nevertheless, this region was able to mediate full promoter activity in the central region of transgenic Vicia hirsuta root nodules.
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A small gene family of broad bean codes for late Nodulins containing conserved cysteine clusters
Plant Science, 2000Co-Authors: Martin Frühling, U. Albus, Natalija Hohnjec, Gerhard Geise, Alfred Pühler, Andreas M. PerlickAbstract:Five transcripts encoding different members of a nodulin family with conserved cysteine clusters (Cys-X-4-Asp-Cys and Cys-X-4-Cys) were identified in broad bean root nodules. They displayed homologies to the early Nodulins PsENOD3 and PsENOD14 and the late nodulin PsNOD6 from pea. In addition to the occurence of putative secretory signal peptides, the spatial distribution of the cysteine residues was comparable in both the broad bean and the pea Nodulins. Based on tissue print hybridizations, we found that the corresponding broad bean genes VfNOD-CCP1, VfNOD-CCP3 and VfNOD-CCP5 were expressed in the interzone II-III and the nitrogen fixing zone III of mature nodules whereas the gene VfNOD-CCP4 was first induced in the prefixing zone II. A strong expression of the VfNOD-CCP2 gene only could be detected the interzone II-III region. Sequence analysis of a genomic VfNOD-CCP1 clone isolated revealed the presence of one intron seperating a first exon encoding the signal peptide from a second exon encoding the cysteine cluster domain of this nodulin. Apart from the multiple presence of the common nodulin motifs AAAGAT and CTCTT on both DNA strands of the putative VfNOD-CCP1 promoter region a sequence element resembling the organ specific element of the soybean lbc3 gene promoter was identified. (C) 2000 Published by Elsevier Science Ireland Ltd. All rights reserved.
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A small gene family of broad bean codes for late Nodulins containing conserved cysteine clusters
'Elsevier BV', 2000Co-Authors: Fruhling M, Albus U, Hohnjec N, Geise G, Pühler Alfred, Andreas M. PerlickAbstract:Fruhling M, Albus U, Hohnjec N, Geise G, Pühler A, Perlick AM. A small gene family of broad bean codes for late Nodulins containing conserved cysteine clusters. PLANT SCIENCE. 2000;152(1):67-77.Five transcripts encoding different members of a nodulin family with conserved cysteine clusters (Cys-X-4-Asp-Cys and Cys-X-4-Cys) were identified in broad bean root nodules. They displayed homologies to the early Nodulins PsENOD3 and PsENOD14 and the late nodulin PsNOD6 from pea. In addition to the occurence of putative secretory signal peptides, the spatial distribution of the cysteine residues was comparable in both the broad bean and the pea Nodulins. Based on tissue print hybridizations, we found that the corresponding broad bean genes VfNOD-CCP1, VfNOD-CCP3 and VfNOD-CCP5 were expressed in the interzone II-III and the nitrogen fixing zone III of mature nodules whereas the gene VfNOD-CCP4 was first induced in the prefixing zone II. A strong expression of the VfNOD-CCP2 gene only could be detected the interzone II-III region. Sequence analysis of a genomic VfNOD-CCP1 clone isolated revealed the presence of one intron seperating a first exon encoding the signal peptide from a second exon encoding the cysteine cluster domain of this nodulin. Apart from the multiple presence of the common nodulin motifs AAAGAT and CTCTT on both DNA strands of the putative VfNOD-CCP1 promoter region a sequence element resembling the organ specific element of the soybean lbc3 gene promoter was identified. (C) 2000 Published by Elsevier Science Ireland Ltd. All rights reserved
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Genomic organization and expression properties of the VfENOD5 gene from broad bean (Vicia faba L.)
'Elsevier BV', 2000Co-Authors: Fruhling M, Hohnjec N, Pühler Alfred, Küster Helge, Schroder G, Andreas M. PerlickAbstract:Fruhling M, Hohnjec N, Schroder G, Küster H, Pühler A, Perlick AM. Genomic organization and expression properties of the VfENOD5 gene from broad bean (Vicia faba L.). PLANT SCIENCE. 2000;155(2):169-178.A full-length cDNA encoding the broad bean (Vicia faba L.) early nodulin VfENOD5 was isolated from a nodule cDNA library. In addition to the ENOD5 homologues from other legumes the derived VfENOD5 amino acid sequence also displayed homologies to the phytocyanin-related Nodulins GmENOD55-2, MtENOD16, and MtENOD20. A close inspection of the ENOD5 proteins from broad bean, pea and vetch indicated that all these Nodulins possess a putative C-terminal GPI-anchor signal sequence. This novel finding supports the hypothesis that ENOD5 is an arabinogalactan protein. Tissue print hybridizations revealed that the broad bean ENOD5 gene was not only expressed in the central tissues of root nodules. In contrast to other legumes hybridizing transcripts were also be detected in a narrow zone within the peripheral nodule tissues. Sequence analysis of a genomic clone indicated the presence of a single intron interrupting the VfENOD5 coding region at a position precisely corresponding to the MtENOD16 and MtENOD20 introns. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved
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Analysis of genes encoding modular Nodulins from Vicia hirsuta and Vicia faba
Plant Science, 1999Co-Authors: Helge Küster, Alfred Pühler, Andreas M. PerlickAbstract:Abstract The expression of genes encoding modular Nodulins was analysed in the Vicia hirsuta and the Vicia faba system. From V. hirsuta root nodules, we isolated two families of transcript sequences designated VhNOD28/32-A and VhNOD28/32-B encoding Nodulins homologous to the V. faba Nodulins Nvf-28/32 and the Medicago sativa nodulin-25. The modular proteins encoded by the V. hirsuta transcript sequences consisted of N- and C-terminal unique modules flanking two types of repetitive modules. Specific repetitive modules were deleted from individual VhNOD28/32 transcripts. Southern hybridizations indicated the presence of either a small VhNOD28/32 gene family or a single copy gene comprising at least two alleles. VhNOD28/32 transcripts were expressed specifically in root nodules, where they were localized in the nitrogen-fixing zone III. In the Vicia faba system, we isolated the promoter of two alleles of the VfNOD28/32 gene by PCR-based DNA walking. The promoter sequences were similar to the promoter of the M. sativa nodulin-25 gene and contained an organ-specific element at position −68/−55 from the transcriptional start. An analysis of transgenic V. hirsut a root nodules expressing the gus Aint reporter gene under the control of the two VfNOD28/32 promoters demonstrated that both promoters were active in the central region of transgenic V . hirsuta nodules.
Alfred Pühler - One of the best experts on this subject based on the ideXlab platform.
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the broad bean nodulin vfenod18 is a member of a novel family of plant proteins with homologies to the bacterial mj0577 superfamily
Molecular Genetics and Genomics, 2000Co-Authors: Natalija Hohnjec, U. Albus, Alfred Pühler, Andreas M. Perlick, Helge Küster, Jörg D. Becker, S C Frosch, Martin FrühlingAbstract:Full-length transcript sequences were isolated from broad bean root nodules, which encode a novel nodulin designated VfENOD18. The corresponding transcripts were detected in early and in late stages of nodule development and were localized exclusively in the nitrogen-fixing zone III. The VfENOD18 sequence is not only homologous to a number of ESTs from various mono- and dicotyledonous plants, but also to the ATP-binding protein MJ0577 from Methanococcus jannaschii and to a range of bacterial proteins that belong to the MJ0577 superfamily. Hence, VfENOD18 is a member of a ubiquitous family of plant proteins that might function as ATP-binding proteins or ATPases. On the genomic level, VfENOD18 genes can be divided into two groups on the basis of differences in their 5' UTRs. One group lacks the 5' UTR region including the ATG initiation codon, whereas the second group contained the complete 5' UTR region. Further upstream of this VfENOD18 gene, a retrotransposon sequence was identified. The -14/-964 VfENOD18 promoter fragment was devoid of complete organ-specific elements known from other nodulin gene promoters. Nevertheless, this region was able to mediate full promoter activity in the central region of transgenic Vicia hirsuta root nodules.
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A small gene family of broad bean codes for late Nodulins containing conserved cysteine clusters
Plant Science, 2000Co-Authors: Martin Frühling, U. Albus, Natalija Hohnjec, Gerhard Geise, Alfred Pühler, Andreas M. PerlickAbstract:Five transcripts encoding different members of a nodulin family with conserved cysteine clusters (Cys-X-4-Asp-Cys and Cys-X-4-Cys) were identified in broad bean root nodules. They displayed homologies to the early Nodulins PsENOD3 and PsENOD14 and the late nodulin PsNOD6 from pea. In addition to the occurence of putative secretory signal peptides, the spatial distribution of the cysteine residues was comparable in both the broad bean and the pea Nodulins. Based on tissue print hybridizations, we found that the corresponding broad bean genes VfNOD-CCP1, VfNOD-CCP3 and VfNOD-CCP5 were expressed in the interzone II-III and the nitrogen fixing zone III of mature nodules whereas the gene VfNOD-CCP4 was first induced in the prefixing zone II. A strong expression of the VfNOD-CCP2 gene only could be detected the interzone II-III region. Sequence analysis of a genomic VfNOD-CCP1 clone isolated revealed the presence of one intron seperating a first exon encoding the signal peptide from a second exon encoding the cysteine cluster domain of this nodulin. Apart from the multiple presence of the common nodulin motifs AAAGAT and CTCTT on both DNA strands of the putative VfNOD-CCP1 promoter region a sequence element resembling the organ specific element of the soybean lbc3 gene promoter was identified. (C) 2000 Published by Elsevier Science Ireland Ltd. All rights reserved.
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Analysis of genes encoding modular Nodulins from Vicia hirsuta and Vicia faba
Plant Science, 1999Co-Authors: Helge Küster, Alfred Pühler, Andreas M. PerlickAbstract:Abstract The expression of genes encoding modular Nodulins was analysed in the Vicia hirsuta and the Vicia faba system. From V. hirsuta root nodules, we isolated two families of transcript sequences designated VhNOD28/32-A and VhNOD28/32-B encoding Nodulins homologous to the V. faba Nodulins Nvf-28/32 and the Medicago sativa nodulin-25. The modular proteins encoded by the V. hirsuta transcript sequences consisted of N- and C-terminal unique modules flanking two types of repetitive modules. Specific repetitive modules were deleted from individual VhNOD28/32 transcripts. Southern hybridizations indicated the presence of either a small VhNOD28/32 gene family or a single copy gene comprising at least two alleles. VhNOD28/32 transcripts were expressed specifically in root nodules, where they were localized in the nitrogen-fixing zone III. In the Vicia faba system, we isolated the promoter of two alleles of the VfNOD28/32 gene by PCR-based DNA walking. The promoter sequences were similar to the promoter of the M. sativa nodulin-25 gene and contained an organ-specific element at position −68/−55 from the transcriptional start. An analysis of transgenic V. hirsut a root nodules expressing the gus Aint reporter gene under the control of the two VfNOD28/32 promoters demonstrated that both promoters were active in the central region of transgenic V . hirsuta nodules.
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Isolation of Two Transcript Sequences of Different Sizes Encoding Modular Nodulins of Vicia hirsuta : Expression Properties and Analysis of Transgenic Nodules Containing Antisense Constructs
Biological Nitrogen Fixation for the 21st Century, 1998Co-Authors: Helge Küster, Alfred Pühler, M. G. Finke, Jörg D. Becker, Andreas M. PerlickAbstract:Nodule-specific transcript sequences of the Vicia faba VfNOD28/32 gene encode six different late Nodulins composed of two types of repetitive sequence modules flanked by unique N- and C-terminal modules (Kuster et al. 1994, 1996). In Medicago sativa, Kiss et al. (1990) and Vegh et al. (1990) identified the MsNOD25 gene encoding the late nodulin Nms-25. Some repetitive and the unique modules were homologous between the Nms-25 and the broad bean Nodulins, but the number and order of repetitive modules was different. This was also the case for the deduced protein sequence of the nodule-specific cDNA Ngo40 from Galega orientalis (S. Karjalainen, personal communication).
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the temporal and spatial transcription pattern in root nodules of vicia faba nodulin genes encoding glycine rich proteins
Plant Molecular Biology, 1997Co-Authors: Gerald Schroder, Martin Frühling, Alfred Pühler, Andreas M. PerlickAbstract:Four different transcript sequences encoding gene products with an unusually high glycine content were identified in Vicia faba root nodules. Northern blot analysis revealed a strong nodule specific expression of the corresponding genes. Time course experiments showed that two of these genes were transcribed before the onset of leghemoglobin expression and hence were designated VfENOD-GRP2 and VfENOD-GRP5, whereas the first detection of VfNOD-GRP1 and VfNOD-GRP4 transcripts coincided with the appearance of leghemoglobin transcripts in V. faba root nodules. A characteristic feature of all encoded Nodulins was a hydrophobic N-terminus, which in the case of the Nodulins ENOD-GRP2 and ENOD-GRP5 has the characteristics of a signal peptide. Such a structure is comparable to other plant glycine-rich proteins described as components of the plant cell wall. Based on tissue print hybridizations, we found that VfNOD-GRP1, VfENOD-GRP2 and VfNOD-GRP4 were expressed in the interzone II-III and in the whole nitrogen-fixing zone III. In contrast to VfENOD-GRP2 and VfNOD-GRP4, the signal intensity of hybridizing VfNOD-GRP1 transcripts was slightly reduced in the more proximal part of broad bean root nodules. Apart from the interzone II-III and the nitrogen fixing zone III, VfENOD-GRP5 RNA was also detected in large areas of the prefixing zone II.
Martin Frühling - One of the best experts on this subject based on the ideXlab platform.
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the broad bean nodulin vfenod18 is a member of a novel family of plant proteins with homologies to the bacterial mj0577 superfamily
Molecular Genetics and Genomics, 2000Co-Authors: Natalija Hohnjec, U. Albus, Alfred Pühler, Andreas M. Perlick, Helge Küster, Jörg D. Becker, S C Frosch, Martin FrühlingAbstract:Full-length transcript sequences were isolated from broad bean root nodules, which encode a novel nodulin designated VfENOD18. The corresponding transcripts were detected in early and in late stages of nodule development and were localized exclusively in the nitrogen-fixing zone III. The VfENOD18 sequence is not only homologous to a number of ESTs from various mono- and dicotyledonous plants, but also to the ATP-binding protein MJ0577 from Methanococcus jannaschii and to a range of bacterial proteins that belong to the MJ0577 superfamily. Hence, VfENOD18 is a member of a ubiquitous family of plant proteins that might function as ATP-binding proteins or ATPases. On the genomic level, VfENOD18 genes can be divided into two groups on the basis of differences in their 5' UTRs. One group lacks the 5' UTR region including the ATG initiation codon, whereas the second group contained the complete 5' UTR region. Further upstream of this VfENOD18 gene, a retrotransposon sequence was identified. The -14/-964 VfENOD18 promoter fragment was devoid of complete organ-specific elements known from other nodulin gene promoters. Nevertheless, this region was able to mediate full promoter activity in the central region of transgenic Vicia hirsuta root nodules.
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A small gene family of broad bean codes for late Nodulins containing conserved cysteine clusters
Plant Science, 2000Co-Authors: Martin Frühling, U. Albus, Natalija Hohnjec, Gerhard Geise, Alfred Pühler, Andreas M. PerlickAbstract:Five transcripts encoding different members of a nodulin family with conserved cysteine clusters (Cys-X-4-Asp-Cys and Cys-X-4-Cys) were identified in broad bean root nodules. They displayed homologies to the early Nodulins PsENOD3 and PsENOD14 and the late nodulin PsNOD6 from pea. In addition to the occurence of putative secretory signal peptides, the spatial distribution of the cysteine residues was comparable in both the broad bean and the pea Nodulins. Based on tissue print hybridizations, we found that the corresponding broad bean genes VfNOD-CCP1, VfNOD-CCP3 and VfNOD-CCP5 were expressed in the interzone II-III and the nitrogen fixing zone III of mature nodules whereas the gene VfNOD-CCP4 was first induced in the prefixing zone II. A strong expression of the VfNOD-CCP2 gene only could be detected the interzone II-III region. Sequence analysis of a genomic VfNOD-CCP1 clone isolated revealed the presence of one intron seperating a first exon encoding the signal peptide from a second exon encoding the cysteine cluster domain of this nodulin. Apart from the multiple presence of the common nodulin motifs AAAGAT and CTCTT on both DNA strands of the putative VfNOD-CCP1 promoter region a sequence element resembling the organ specific element of the soybean lbc3 gene promoter was identified. (C) 2000 Published by Elsevier Science Ireland Ltd. All rights reserved.
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the temporal and spatial transcription pattern in root nodules of vicia faba nodulin genes encoding glycine rich proteins
Plant Molecular Biology, 1997Co-Authors: Gerald Schroder, Martin Frühling, Alfred Pühler, Andreas M. PerlickAbstract:Four different transcript sequences encoding gene products with an unusually high glycine content were identified in Vicia faba root nodules. Northern blot analysis revealed a strong nodule specific expression of the corresponding genes. Time course experiments showed that two of these genes were transcribed before the onset of leghemoglobin expression and hence were designated VfENOD-GRP2 and VfENOD-GRP5, whereas the first detection of VfNOD-GRP1 and VfNOD-GRP4 transcripts coincided with the appearance of leghemoglobin transcripts in V. faba root nodules. A characteristic feature of all encoded Nodulins was a hydrophobic N-terminus, which in the case of the Nodulins ENOD-GRP2 and ENOD-GRP5 has the characteristics of a signal peptide. Such a structure is comparable to other plant glycine-rich proteins described as components of the plant cell wall. Based on tissue print hybridizations, we found that VfNOD-GRP1, VfENOD-GRP2 and VfNOD-GRP4 were expressed in the interzone II-III and in the whole nitrogen-fixing zone III. In contrast to VfENOD-GRP2 and VfNOD-GRP4, the signal intensity of hybridizing VfNOD-GRP1 transcripts was slightly reduced in the more proximal part of broad bean root nodules. Apart from the interzone II-III and the nitrogen fixing zone III, VfENOD-GRP5 RNA was also detected in large areas of the prefixing zone II.
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the modular Nodulins nvf 28 32 of broad bean vicia faba l alternative exon combinations account for different modular structures
Molecular Genetics and Genomics, 1996Co-Authors: Helge Küster, Martin Frühling, Alfred Pühler, Andreas M. PerlickAbstract:The broad bean late Nodulins, Nvf-28/32, are composed of two types of repetitively occurring sequence modules flanked by unique N- and C-terminal modules. Six isoforms of these Nodulins were characterized by a specific modular structure resulting from a different individual order of repetitive sequence modules. A detailed analysis of genomic PCR fragments revealed that the repetitive modules and the N-terminal unique module exactly corresponded to exons, whereas the C-terminal module was specified by two exons. Since those exons encoding the repetitive modules missing in specific Nvf-28/32 isoforms were consistently present within genomic sequences, a post-transcriptional generation of VfNOD28/32 transcripts specifying six Nvf-28/32 Nodulins was concluded. Using tissue-print hybridizations, these transcripts were localized in the interzone II–III and the nitrogen-fixing zone III of root nodules. From this and from cDNA-cDNA hybridizations demonstrating a comparable timing of expression of VfNOD28/32 and of leghemoglobin transcripts in root nodules, a function of the modular Nodulins Nvf-28/32 in late developmental stages of broad bean nodules was inferred.
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the nodule specific vfenod grp3 gene encoding a glycine rich early nodulin is located on chromosome i of vicia faba l and is predominantly expressed in the interzone ii iii of root nodules
Plant Molecular Biology, 1995Co-Authors: Helge Küster, Martin Frühling, Andreas M. Perlick, Gerald Schroder, Uta Pich, Mechthild Rieping, Ingo Schubert, Alfred PühlerAbstract:A nodule-specific cDNA was isolated from a Vicia faba L. nodule cDNA library. Since time course experiments revealed an early expression of this transcript in the nodule, this cDNA coded for an early nodulin and was designated VfENOD-GRP3. Based on tissue print hybridizations, we found a predominant expression of VfENOD-GRP3 transcripts in the interzone II-III region of broad bean root nodules. The encoded early nodulin ENOD-GRP3 was characterized by an N-terminal signal peptide and a C-terminal domain displaying a glycine content of 31%. Sequence analysis of a genomic VfENOD-GRP3 clone revealed that the signal peptide and the glycine-rich domain were specified by two separate exons. Primer extension experiments identified two adjacent transcription start sites for VfENOD-GRP3 transcripts. The common nodulin sequences ‘AAAGAT’ and ‘CTCTT’ were present five and three times on both DNA strands of the putative VfENOD-GRP3 promoter, respectively. Additionally, three sequence motifs resembling organ-specific elements of the soybean lbc3 gene promoter and a sequence similar to the binding site 1 for the nodule trans-acting factor Nat2 were identified. From Southern blot data and from sequence analysis of genomic PCR fragments, the presence of a VfENOD-GRP3 gene family was inferred. By PCR experiments using sequence-specific primers and DNA of microisolated chromosomes as a template, this family was located on the long arm of chromosome I.
Helge Küster - One of the best experts on this subject based on the ideXlab platform.
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the signal peptide of the medicago truncatula modular nodulin mtnod25 operates as an address label for the specific targeting of proteins to nitrogen fixing symbiosomes
Molecular Plant-microbe Interactions, 2009Co-Authors: Natalija Hohnjec, Frauke Lenz, Vera Fehlberg, Martin F Vieweg, Markus C Baier, Bettina Hause, Helge KüsterAbstract:The nodule-specific MtNOD25 gene of the model legume Medicago truncatula encodes a modular nodulin composed of different repetitive modules flanked by distinct N- and C-termini. Although similarities are low with respect to all repetitive modules, both the N-terminal signal peptide (SP) and the C-terminus are highly conserved in modular Nodulins from different legumes. On the cellular level, MtNOD25 is only transcribed in the infected cells of root nodules, and this activation is mediated by a 299-bp minimal promoter containing an organ-specific element. By expressing mGFP6 translational fusions in transgenic nodules, we show that MtNOD25 proteins are exclusively translocated to the symbiosomes of infected cells. This specific targeting only requires an N-terminal MtNOD25 SP that is highly conserved across a family of legume-specific symbiosome proteins. Our finding sheds light on one possible mechanism for the delivery of host proteins to the symbiosomes of infected root nodule cells and, in addition, defines a short molecular address label of only 24 amino acids whose N-terminal presence is sufficient to translocate proteins across the peribacteroid membrane.
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the broad bean nodulin vfenod18 is a member of a novel family of plant proteins with homologies to the bacterial mj0577 superfamily
Molecular Genetics and Genomics, 2000Co-Authors: Natalija Hohnjec, U. Albus, Alfred Pühler, Andreas M. Perlick, Helge Küster, Jörg D. Becker, S C Frosch, Martin FrühlingAbstract:Full-length transcript sequences were isolated from broad bean root nodules, which encode a novel nodulin designated VfENOD18. The corresponding transcripts were detected in early and in late stages of nodule development and were localized exclusively in the nitrogen-fixing zone III. The VfENOD18 sequence is not only homologous to a number of ESTs from various mono- and dicotyledonous plants, but also to the ATP-binding protein MJ0577 from Methanococcus jannaschii and to a range of bacterial proteins that belong to the MJ0577 superfamily. Hence, VfENOD18 is a member of a ubiquitous family of plant proteins that might function as ATP-binding proteins or ATPases. On the genomic level, VfENOD18 genes can be divided into two groups on the basis of differences in their 5' UTRs. One group lacks the 5' UTR region including the ATG initiation codon, whereas the second group contained the complete 5' UTR region. Further upstream of this VfENOD18 gene, a retrotransposon sequence was identified. The -14/-964 VfENOD18 promoter fragment was devoid of complete organ-specific elements known from other nodulin gene promoters. Nevertheless, this region was able to mediate full promoter activity in the central region of transgenic Vicia hirsuta root nodules.
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Analysis of genes encoding modular Nodulins from Vicia hirsuta and Vicia faba
Plant Science, 1999Co-Authors: Helge Küster, Alfred Pühler, Andreas M. PerlickAbstract:Abstract The expression of genes encoding modular Nodulins was analysed in the Vicia hirsuta and the Vicia faba system. From V. hirsuta root nodules, we isolated two families of transcript sequences designated VhNOD28/32-A and VhNOD28/32-B encoding Nodulins homologous to the V. faba Nodulins Nvf-28/32 and the Medicago sativa nodulin-25. The modular proteins encoded by the V. hirsuta transcript sequences consisted of N- and C-terminal unique modules flanking two types of repetitive modules. Specific repetitive modules were deleted from individual VhNOD28/32 transcripts. Southern hybridizations indicated the presence of either a small VhNOD28/32 gene family or a single copy gene comprising at least two alleles. VhNOD28/32 transcripts were expressed specifically in root nodules, where they were localized in the nitrogen-fixing zone III. In the Vicia faba system, we isolated the promoter of two alleles of the VfNOD28/32 gene by PCR-based DNA walking. The promoter sequences were similar to the promoter of the M. sativa nodulin-25 gene and contained an organ-specific element at position −68/−55 from the transcriptional start. An analysis of transgenic V. hirsut a root nodules expressing the gus Aint reporter gene under the control of the two VfNOD28/32 promoters demonstrated that both promoters were active in the central region of transgenic V . hirsuta nodules.
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Isolation of Two Transcript Sequences of Different Sizes Encoding Modular Nodulins of Vicia hirsuta : Expression Properties and Analysis of Transgenic Nodules Containing Antisense Constructs
Biological Nitrogen Fixation for the 21st Century, 1998Co-Authors: Helge Küster, Alfred Pühler, M. G. Finke, Jörg D. Becker, Andreas M. PerlickAbstract:Nodule-specific transcript sequences of the Vicia faba VfNOD28/32 gene encode six different late Nodulins composed of two types of repetitive sequence modules flanked by unique N- and C-terminal modules (Kuster et al. 1994, 1996). In Medicago sativa, Kiss et al. (1990) and Vegh et al. (1990) identified the MsNOD25 gene encoding the late nodulin Nms-25. Some repetitive and the unique modules were homologous between the Nms-25 and the broad bean Nodulins, but the number and order of repetitive modules was different. This was also the case for the deduced protein sequence of the nodule-specific cDNA Ngo40 from Galega orientalis (S. Karjalainen, personal communication).
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the modular Nodulins nvf 28 32 of broad bean vicia faba l alternative exon combinations account for different modular structures
Molecular Genetics and Genomics, 1996Co-Authors: Helge Küster, Martin Frühling, Alfred Pühler, Andreas M. PerlickAbstract:The broad bean late Nodulins, Nvf-28/32, are composed of two types of repetitively occurring sequence modules flanked by unique N- and C-terminal modules. Six isoforms of these Nodulins were characterized by a specific modular structure resulting from a different individual order of repetitive sequence modules. A detailed analysis of genomic PCR fragments revealed that the repetitive modules and the N-terminal unique module exactly corresponded to exons, whereas the C-terminal module was specified by two exons. Since those exons encoding the repetitive modules missing in specific Nvf-28/32 isoforms were consistently present within genomic sequences, a post-transcriptional generation of VfNOD28/32 transcripts specifying six Nvf-28/32 Nodulins was concluded. Using tissue-print hybridizations, these transcripts were localized in the interzone II–III and the nitrogen-fixing zone III of root nodules. From this and from cDNA-cDNA hybridizations demonstrating a comparable timing of expression of VfNOD28/32 and of leghemoglobin transcripts in root nodules, a function of the modular Nodulins Nvf-28/32 in late developmental stages of broad bean nodules was inferred.
Daniel M Roberts - One of the best experts on this subject based on the ideXlab platform.
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the nodulin 26 intrinsic protein subfamily
2017Co-Authors: Daniel M Roberts, Pratyush RoutrayAbstract:Nodulin intrinsic proteins (NIPs) represent a land plant-specific subfamily of the major intrinsic protein/aquaporin superfamily. NIPs are named for the first member of the family discovered, soybean nodulin 26 of symbiotic nitrogen-fixing root nodules. Evolutionarily, NIPs appear in early nonvascular and vascular land plant lineages, with the family undergoing substantial diversification and sub-functionalization during subsequent evolution of seed plants. Structurally, most NIPs can be divided into three “pore” families based on the composition of amino acids comprising the predicted aromatic-arginine selectivity region of the channel pore. Functionally, two of these families (NIP II and NIP III) serve as channels for metalloid nutrients (boric acid and silicic acid respectively), while the biological role of NIP I channels remains more open. Biochemical functions for NIP proteins are diverse, with transport selectivities ranging from metalloid hydroxides to glycerol, lactic acid, urea, and hydrogen peroxide. Some NIPs retain their aquaporin function, while others have lost this signature activity of the aquaporin family. In the present chapter, the evolutionary origins, structural and functional properties, and potential biological functions, particularly beyond their roles as metalloid facilitators, are reviewed.
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arabidopsis nip2 1 a major intrinsic protein transporter of lactic acid induced by anoxic stress
Journal of Biological Chemistry, 2007Co-Authors: Wongyu Choi, Daniel M RobertsAbstract:Nodulin 26 intrinsic proteins (NIPs) are plant-specific, highly conserved water and solute transport proteins with structural and functional homology to soybean nodulin 26. Arabidopsis thaliana contains nine NIP genes. In this study, it is shown that one of these, AtNIP2;1, is exquisitely sensitive to water logging and anoxia stress. Based on quantitative PCR and promoter::GUS experiments, AtNIP2;1 is expressed at a low basal level in the root tips and the vascular bundle of differentiated roots. Transcript levels are elevated acutely and rapidly upon water logging of root or leaf tissues, increasing 70-fold in roots within the 1st h of submersion. After this large initial increase, mRNA levels decline to steady state levels that remain over 10-fold higher by 6 h post-submersion. An even greater induction of AtNIP2;1 expression was observed upon anoxia challenge of Arabidopsis seedlings, with a 300-fold increase in AtNIP2;1 transcript observed by 2 h after the initiation of oxygen deprivation. Functional analysis of AtNIP2;1 expressed in Xenopus oocytes shows that the protein differs from soybean nodulin 26, showing minimal water and glycerol transport. Instead, AtNIP2;1 displays transport of lactic acid, with a preference for the protonated acidic form of this weak acid. Overall, the data suggest that AtNIP2;1 is an anaerobic-induced gene that encodes a lactic acid transporter and may play a role in adaptation to lactic fermentation under anaerobic stress.
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the structure function and regulation of the nodulin 26 like intrinsic protein family of plant aquaglyceroporins
Biochimica et Biophysica Acta, 2006Co-Authors: Ian S Wallace, Wongyu Choi, Daniel M RobertsAbstract:The nodulin 26-like intrinsic protein family is a group of highly conserved multifunctional major intrinsic proteins that are unique to plants, and which transport a variety of uncharged solutes ranging from water to ammonia to glycerol. Based on structure–function studies, the NIP family can be subdivided into two subgroups (I and II) based on the identity of the amino acids in the selectivity-determining filter (ar/R region) of the transport pore. Both subgroups appear to contain multifunctional transporters with low to no water permeability and the ability to flux multiple uncharged solutes of varying sizes depending upon the composition of the residues of the ar/R filter. NIPs are subject to posttranslational phosphorylation by calcium-dependent protein kinases. In the case of the family archetype, soybean nodulin 26, phosphorylation has been shown to stimulate its transport activity and to be regulated in response to developmental as well as environmental cues, including osmotic stresses. NIPs tend to be expressed at low levels in the plant compared to other MIPs, and several exhibit cell or tissue specific expression that is subject to spatial and temporal regulation during development.
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distinct transport selectivity of two structural subclasses of the nodulin like intrinsic protein family of plant aquaglyceroporin channels
Biochemistry, 2005Co-Authors: Ian S Wallace, Daniel M RobertsAbstract:Major intrinsic proteins (MIPs) are a diverse class of integral membrane proteins that facilitate the transport of water and some small solutes across cellular membranes. X-ray structures of MIPs indicate that a tetrad of residues (the ar/R region) form a narrow pore constriction that constitutes the selectivity filter. In comparison with mammalian and microbial species, plants have a greater number and diversity of MIPs with greater than 30 genes encoding four phylogenetic subfamilies with eight different classes of ar/R sequences. The nodulin 26-like intrinsic protein (NIP) subfamily in Arabidopsis can be subdivided into two ar/R subgroups: the NIP subgroup I, which resembles the archetype of the family, soybean nodulin 26, and the NIP subgroup II, which is represented by the Arabidopsis protein AtNIP6;1. These two NIPs differ principally by the substitution of a conserved alanine (NIP subgroup II) for a conserved tryptophan (NIP subgroup I) in the helix 2 position (H2) of the ar/R filter. A comparison of the water and solute tranport properties of the two proteins was performed by expression in Xenopus laevis oocytes. Nodulin 26 is an aquaglyceroporin with a modest osmotic water permeability (P(f)) and the ability to transport uncharged solutes such as glycerol and formamide. In constrast, AtNIP6;1 showed no measurable water permeability but transported glycerol, formamide, as well as larger solutes that were impermeable to nodulin 26. By site-directed mutagenesis, we show that the H2 position is the crucial determinant that confers these transport behaviors. A comparison of the NIPs and tonoplast-intrinsic proteins (TIP) shows that the H2 residue can predict the transport profile for water and glycerol with histidine found in TIP-like aquaporins, tryptophan found in aquaglyceroporins (NIP I), and alanine found in water-impermeable glyceroporins (AtNIP6;1).
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distinct transport selectivity of two structural subclasses of the nodulin like intrinsic protein family of plant aquaglyceroporin channels
Biochemistry, 2005Co-Authors: Ian S Wallace, Daniel M RobertsAbstract:Major intrinsic proteins (MIPs) are a diverse class of integral membrane proteins that facilitate the transport of water and some small solutes across cellular membranes. X-ray structures of MIPs indicate that a tetrad of residues (the ar/R region) form a narrow pore constriction that constitutes the selectivity filter. In comparison with mammalian and microbial species, plants have a greater number and diversity of MIPs with greater than 30 genes encoding four phylogenetic subfamilies with eight different classes of ar/R sequences. The nodulin 26-like intrinsic protein (NIP) subfamily in Arabidopsis can be subdivided into two ar/R subgroups: the NIP subgroup I, which resembles the archetype of the family, soybean nodulin 26, and the NIP subgroup II, which is represented by the Arabidopsis protein AtNIP6;1. These two NIPs differ principally by the substitution of a conserved alanine (NIP subgroup II) for a conserved tryptophan (NIP subgroup I) in the helix 2 position (H2) of the ar/R filter. A comparison...