Rhizobium common nod genes are required for biofilm formation (2008)
Fujishige, Nancy A, Lum, Michelle R, De Hoff, Peter L, Whitelegge, Julian P, Faull, Kym F, Hirsch, Ann M
In legume nitrogen-fixing symbioses, rhizobial nod genes are obligatory for initiating infection thread formation and root nodule development. Here we show that the common nod genes, nodD1ABC, whose...
Investigations of Rhizobium biofilm formation (2006)
Fujishige, Nancy A, Kapadia, Neel N, De Hoff, Peter L, Hirsch, Ann M
The development of nitrogen-fixing nodules of the Rhizobium-legume symbiosis, especially the early stages of root hair deformation and curling, infection thread formation, and nodule initiation, has...
Investigations of Rhizobium biofilm formation. (2006)
Fujishige, Nancy A, Kapadia, Neel N, De Hoff, Peter L, Hirsch, Ann M
The development of nitrogen-fixing nodules of the Rhizobium-legume symbiosis, especially the early stages of root hair deformation and curling, infection thread formation, and nodule initiation, has...
Investigations of Rhizobium biofilm formation. (2006)
Fujishige, Nancy A, Kapadia, Neel N, De Hoff, Peter L, Hirsch, Ann M
The development of nitrogen-fixing nodules of the Rhizobium-legume symbiosis, especially the early stages of root hair deformation and curling, infection thread formation, and nodule initiation, has...
A feeling for the micro-organism: structure on a small scale. Biofilms on plant roots (2006)
Fujishige, N A, Kapadia, N N, Hirsch, Ann M
Biofilms are structured communities of bacterial cells enclosed in a self-produced polymeric matrix and adherent to an inert or living surface; they have clinical, industrial and environmental...
Valdés, MarÃa, Pérez, Néstor-Octavio, Caballero-Mellado, Jesús, Peña-Cabriales, Juan José, Normand, Philippe, ...
Based on partial 16S sequences, we previously described a novel group of nonsymbiotic, acetylene reduction activity-positive actinomycetes which were isolated from surface-sterilized roots of...
Expansins are a highly conserved group of cell wall-localized proteins that appear to mediate changes in cell wall plasticity during cell expansion or differentiation. The accumulation of expansin...
Wildman, S G, Hirsch, Ann M, Kirchanski, S J, Spencer, D
In 1980, Wildman et al. (Bot Gaz 141: 24-36) proposed a three-dimensional model for chloroplast structure whereby the grana were arranged in non-overlapping rows, like beads on a string. This...
Expression of MsLEC1 transgenes in alfalfa plants causes symbiotic abnormalities (2004)
Brill, Laurence M, Fujishige, Nancy A, Hackworth, Cheryl A, Hirsch, Ann M
Legume lectins have been proposed to have important symbiotic roles during Rhizobium-legume symbioses. To test this hypothesis, the symbiotic responses of transgenic alfalfa plants that express a...
Plant-microbe symbioses: A continuum from commensalism to parasitism (2004)
Photosynthetic organisms establish symbioses with a wide range of microorganisms. This review examines the diversity of symbiotic interactions, and proposes that there is a continuum from...
Karlowski, Wojciech M, Hirsch, Ann M
The alfalfa MsRH2-1 gene encodes a small protein with a RING-H2 motif and an N-terminal transmembrane domain. The transcript can be found in all tested plant organs, but roots and nodules show the...
Hirsch, Ann M, Bauer, W D, Bird, D M, Cullimore, J, Tyler, B, Yoder, J I
Rhizosphere interactions are affected by many different regulatory signals. As yet, however, only a few have been identified. Signals, by definition, contain information, react with a receptor, and...
Lum, Michelle R., Li, Ying, LaRue, Thomas A., David-Schwartz, Rakefet, Kapulnik, Yoram, Hirsch, Ann M.
The nitrogen-fixing symbiosis between Rhizobiaceae and legumes is one of the best-studied interactions established between prokaryotes and eukaryotes. The plant develops root nodules in which the...
Effects of Oxygen on Nodule Physiology and Expression of Nodulins in Alfalfa1
Wycoff, Keith L., Hunt, Stephen, Gonzales, Michael B., VandenBosch, Kathryn A., Layzell, David B., Hirsch, Ann M.
Early nodulin 2 (ENOD2) transcripts and protein are specifically found in the inner cortex of legume nodules, a location that coincides with the site of a barrier to O2 diffusion. The extracellular...
ENOD40, an early nodulin gene, is expressed following inoculation with Rhizobium meliloti or by adding R. meliloti-produced nodulation (Nod) factors or the plant hormone cytokinin to uninoculated...
Dg93, a Nodule-Abundant mRNA of Datisca glomerata with Homology to a Soybean Early Nodulin Gene1
Okubara, Patricia A., Fujishige, Nancy A., Hirsch, Ann M., Berry, Alison M.
We have isolated a 590-bp full-length cDNA clone designated Dg93, an mRNA that is highly expressed in symbiotic root nodules of the actinorhizal host Datisca glomerata. Dg93 mRNA encodes a deduced...
Oxygen Regulation of a Nodule-Located Carbonic Anhydrase in Alfalfa1
Gálvez, Susana, Hirsch, Ann M., Wycoff, Keith L., Hunt, Stephen, Layzell, David B., Kondorosi, Adam, ...
Control of the permeability to oxygen is critical for the function of symbiotic nitrogen fixation in legume nodules. The inner cortex (IC) seems to be a primary site for this regulation. In alfalfa...
Van Rhijn, Pieternel, Fujishige, Nancy A., Lim, Pyung Ok, Hirsch, Ann M.
Transgenic alfalfa (Medicago sativa L. cv Regen) roots carrying genes encoding soybean lectin or pea (Pisum sativum) seed lectin (PSL) were inoculated with Bradyrhizobium japonicum or Rhizobium...
Woo, Ho-Hyung, Faull, Kym F., Hirsch, Ann M., Hawes, Martha C.
Alfalfa (Medicago sativa) and Arabidopsis were used as model systems to examine molecular mechanisms underlying developmental effects of a microsomal UDP-glucuronosyltransferase-encoding gene from...
Excised juvenile leaves of Microgramma vacciniifolia (Polypodiaceae) develop sporophytic regenerants when grown on mineral agar with sucrose. The ratio of sporophytes to gametophytes produced from...
Valdés, María, Pérez, Néstor-Octavio, Caballero-Mellado, Jesús, Peña-Cabriales, Juan José, Normand, Philippe, ...
Based on partial 16S sequences, we previously described a novel group of nonsymbiotic, acetylene reduction activity-positive actinomycetes which were isolated from surface-sterilized roots of...
Norris, Joanna H., Macol, Lisa A., Hirsch, Ann M.
Nodulin gene expression was analyzed in effective and ineffective root nodules of alfalfa (Medicago sativa L. cv Iroquois) elicited by three different Rhizobium meliloti mutants: an exoB mutant...
Scheres, Ben, McKhann, Heather I., Zalensky, Andrei, Löbler, Marian, Bisseling, Ton, Hirsch, Ann M.
A number of early nodulin genes are expressed in specific cell types as pea (Pisum sativum) root nodules develop. The Pisum sativum early nodulin PsENOD2 is detected only in the uninfected cells of...
sym 13—A Gene Conditioning Ineffective Nodulation in Pisum sativum1
Kneen, Barbara E., LaRue, Thomas A., Hirsch, Ann M., Smith, Carol A., Weeden, Norman F.
Treatment of Pisum sativum (L.) cv. `Sparkle' with ethyl methanesulfonic acid (EMS) produced a stable mutant, E135F, which forms small, white, ineffective nodules. These nodules exhibit histological...
Yang, Cheng, Signer, Ethan R., Hirsch, Ann M.
Infection of alfalfa with Rhizobium meliloti exo mutants deficient in exopolysaccharide results in abnormal root nodules that are devoid of bacteria and fail to fix nitrogen. Here we report further...
Effects of Oxygen on Nodule Physiology and Expression of Nodulins in Alfalfa1
Wycoff, Keith L., Hunt, Stephen, Gonzales, Michael B., VandenBosch, Kathryn A., Layzell, David B., Hirsch, Ann M.
Early nodulin 2 (ENOD2) transcripts and protein are specifically found in the inner cortex of legume nodules, a location that coincides with the site of a barrier to O2 diffusion. The extracellular...
ENOD40, an early nodulin gene, is expressed following inoculation with Rhizobium meliloti or by adding R. meliloti-produced nodulation (Nod) factors or the plant hormone cytokinin to uninoculated...
Dg93, a Nodule-Abundant mRNA of Datisca glomerata with Homology to a Soybean Early Nodulin Gene1
Okubara, Patricia A., Fujishige, Nancy A., Hirsch, Ann M., Berry, Alison M.
We have isolated a 590-bp full-length cDNA clone designated Dg93, an mRNA that is highly expressed in symbiotic root nodules of the actinorhizal host Datisca glomerata. Dg93 mRNA encodes a deduced...
Oxygen Regulation of a Nodule-Located Carbonic Anhydrase in Alfalfa1
Gálvez, Susana, Hirsch, Ann M., Wycoff, Keith L., Hunt, Stephen, Layzell, David B., Kondorosi, Adam, ...
Control of the permeability to oxygen is critical for the function of symbiotic nitrogen fixation in legume nodules. The inner cortex (IC) seems to be a primary site for this regulation. In alfalfa...
Van Rhijn, Pieternel, Fujishige, Nancy A., Lim, Pyung Ok, Hirsch, Ann M.
Transgenic alfalfa (Medicago sativa L. cv Regen) roots carrying genes encoding soybean lectin or pea (Pisum sativum) seed lectin (PSL) were inoculated with Bradyrhizobium japonicum or Rhizobium...
Woo, Ho-Hyung, Faull, Kym F., Hirsch, Ann M., Hawes, Martha C.
Alfalfa (Medicago sativa) and Arabidopsis were used as model systems to examine molecular mechanisms underlying developmental effects of a microsomal UDP-glucuronosyltransferase-encoding gene from...
Excised juvenile leaves of Microgramma vacciniifolia (Polypodiaceae) develop sporophytic regenerants when grown on mineral agar with sucrose. The ratio of sporophytes to gametophytes produced from...
Valdés, María, Pérez, Néstor-Octavio, Caballero-Mellado, Jesús, Peña-Cabriales, Juan José, Normand, Philippe, ...
Based on partial 16S sequences, we previously described a novel group of nonsymbiotic, acetylene reduction activity-positive actinomycetes which were isolated from surface-sterilized roots of...
Norris, Joanna H., Macol, Lisa A., Hirsch, Ann M.
Nodulin gene expression was analyzed in effective and ineffective root nodules of alfalfa (Medicago sativa L. cv Iroquois) elicited by three different Rhizobium meliloti mutants: an exoB mutant...
Scheres, Ben, McKhann, Heather I., Zalensky, Andrei, Löbler, Marian, Bisseling, Ton, Hirsch, Ann M.
A number of early nodulin genes are expressed in specific cell types as pea (Pisum sativum) root nodules develop. The Pisum sativum early nodulin PsENOD2 is detected only in the uninfected cells of...
sym 13—A Gene Conditioning Ineffective Nodulation in Pisum sativum1
Kneen, Barbara E., LaRue, Thomas A., Hirsch, Ann M., Smith, Carol A., Weeden, Norman F.
Treatment of Pisum sativum (L.) cv. `Sparkle' with ethyl methanesulfonic acid (EMS) produced a stable mutant, E135F, which forms small, white, ineffective nodules. These nodules exhibit histological...
Yang, Cheng, Signer, Ethan R., Hirsch, Ann M.
Infection of alfalfa with Rhizobium meliloti exo mutants deficient in exopolysaccharide results in abnormal root nodules that are devoid of bacteria and fail to fix nitrogen. Here we report further...
Lee, Angie, Lum, Michelle R, Hirsch, Ann M
Several nonnodulating, nonmycorrhizal (Nod−Myc−) mutants of Melilotus alba Desr. (white sweetclover) have been described. However, the details of their responses to Sinorhizobium meliloti have...
Signals and Responses: Choreographing the Complex Interaction between Legumes and α- and β-Rhizobia
The nitrogen-fixing symbiosis between bacteria in the family Rhizobiaceae and members of the legume family (Fabaceae) has been well studied, particularly from the perspective of the early signaling...
Lee, Angie, Giordano, Walter, Hirsch, Ann M
We previously showed that applying 10−6 M of the cytokinin 6-benzylaminopurine (BAP) to uninoculated roots of Masym3, a Nod−Myc− Melilotus alba (Desr.) mutant, resulted in the accumulation of...
Plant lectins: the ties that bind in root symbiosis and plant defense
De Hoff, Peter L., Brill, Laurence M., Hirsch, Ann M.
Lectins are a diverse group of carbohydrate-binding proteins that are found within and associated with organisms from all kingdoms of life. Several different classes of plant lectins serve a diverse...