Iron (Fe) deficiency is a widespread nutritional disorder on calcareous soils. To identify genes ... more Iron (Fe) deficiency is a widespread nutritional disorder on calcareous soils. To identify genes involved in the Fe deficiency response, Arabidopsis (Arabidopsis thaliana) transfer DNA insertion lines were screened on a high-pH medium with low Fe availability. This approach identified METAL TOLERANCE PROTEIN8 (MTP8), a member of the Cation Diffusion Facilitator family, as a critical determinant for the tolerance to Fe deficiency-induced chlorosis, also on soil substrate. Subcellular localization to the tonoplast, complementation of a manganese (Mn)-sensitive Saccharomyces cerevisiae yeast strain, and Mn sensitivity of mtp8 knockout mutants characterized the protein as a vacuolar Mn transporter suitable to prevent plant cells from Mn toxicity. MTP8 expression was strongly induced on low-Fe as well as high-Mn medium, which were both strictly dependent on the transcription factor FIT, indicating that high-Mn stress induces Fe deficiency. mtp8 mutants were only hypersensitive to Fe deficiency when Mn was present in the medium, which further suggested an Mn-specific role of MTP8 during Fe limitation. Under those conditions, mtp8 mutants not only translocated more Mn to the shoot than did wild-type plants but suffered in particular from critically low Fe concentrations and, hence, Fe chlorosis, although the transcriptional Fe deficiency response was up-regulated more strongly in mtp8. The diminished uptake of Fe from Mn-containing low-Fe medium by mtp8 mutants was caused by an impaired ability to boost the ferric chelate reductase activity, which is an essential process in Fe acquisition. These findings provide a mechanistic explanation for the long-known interference of Mn in Fe nutrition and define the molecular processes by which plants alleviate this antagonism.
Abstract Healthy plant growth depends on a balanced metal homeostasis at the organ, tissue and su... more Abstract Healthy plant growth depends on a balanced metal homeostasis at the organ, tissue and sub-cellular levels, which is mediated principally by plasma and vacuolar membrane metal transporters. The genetic bases of metal acquisition in developing seeds has long remained poorly understood. Recent technical advances have helped circumvent the difficulties of conducting metal nutrient research on the extremely small seeds of Arabidopsis thaliana . The review presents recent advances in our understanding of seed metal homeostasis focussing on this model plant. Metals are loaded from phloem to the seed coat and must pass through the endosperm to reach the embryo. The embryo comprises several apoplastic and symplastic pathways that strictly depend on the changing physiology of the developing seed organs. Metals that reach the developing embryo fuel immediate cellular processes or accumulate in vacuoles to support forthcoming germination. In the mature embryo, metal distribution is homogeneous, with the exception of iron and manganese which localize to distinct cell layers. These metal localizations are strictly dependent on expression of specific tonoplast transporters, with putative functions that go beyond the storage of metals. Accumulating evidence indicates that they can control the timing of metal entry into the embryo.
In plant cells, either excess or insufficient iron (Fe) concentration triggers stress responses, ... more In plant cells, either excess or insufficient iron (Fe) concentration triggers stress responses, therefore it is strictly controlled. Proteasome-mediated degradation through ubiquitination of Fe homeostasis proteins has just become the focus of research in recent years. Deactivating ubiquitin ligases, COP9 signalosome has a central importance in the translational control of various stress responses. The aim of the study was to investigate COP9 signalosome in Fe deficiency response of Strategy I plants. In silico analysis of a set of Fe-deficiency-responsive genes was conducted against the transcriptome of Arabidopsis csn mutant lines using Genevestigator software. Induced and suppressed genes were clustered in a hierarchical way and gene ontology enrichment categories were identified. In wild-type Arabidopsis, CSN genes did not respond to iron deficiency. In csn mutant lines, under Fe-sufficient conditions, hundreds of Fe-deficiency-responsive genes were misregulated. Among the ones previously characterized for their physiological roles under Fe deficiency IRT1, NAS4, BTS, NRAMP1 were down-regulated while AHA2, MTP8, FRD3 were up-regulated. Unexpectedly, from those which were regulated in opposite ways, some had been repeatedly shown to be tightly co-regulated by the same transcription factor, FIT. Two proteins from DELLA family, which were reported to interact with FIT to repress its downstream, were found to be strikingly repressed in csn mutants. Overall, the study underlined that the absence of a functional CSN greatly impacted the regulation of Fe homeostasis-related genes, in a manner which cannot be explained simply by the induction of the master transcription factor, FIT. Correct expression of Fe deficiency-responsive genes requires an intact COP9 signalosome in Arabidopsis.
Manufacturing high-profit goods in the information and technology age requires solid foundations ... more Manufacturing high-profit goods in the information and technology age requires solid foundations in basic sciences. However, despite their interests and high success, basic sciences often fail to attract university candidates due to the perceived job insecurity after graduation. To challenge this notion, the current study aimed to examine biology graduates’ profiles and career life. As a survey study, an online questionnaire was administered to 56 graduates of the biological sciences department. The findings showed that almost all graduates chose biology due to their interest in the first place. The majority thought that their undergraduate education prepared them effectively for their future career, and they acquired 21st-century skills adequately, except for entrepreneurship skills. They found a job related to their major in one to two years. They were primarily employed in universities and got academic positions. They were satisfied with their jobs. The study concluded that highe...
Background and purpose: Synthetic fertilizers damage the environment. Biofertilizers that consist... more Background and purpose: Synthetic fertilizers damage the environment. Biofertilizers that consist of microorganisms emerge as an environmentally friendly alternative. Biofertilizers improve plant growth by mobilizing soil nutrients, triggering plant hormone synthesis, or competing with pathogenic bacteria. However, biofertilizers often fail due to insufficient colonization of the plant roots.Materials and methods: To explore the colonization dynamics of a bacterial strain commonly used in biofertilizers, Bacillus subtilis OSU-142 (OSU-142), developing a set of primers specific to OSU-142 was aimed. Since its genome is unknown, to identify genomic regions unique to OSU-142 strain, DNAs of more than 40 bacterial strains were fingerprinted, most of which belong to Bacillus subtilis using the Randomly Amplified Polymorphic DNA (RAPD) method.Results: This approach identified a polymorphic band at 880 bp, which was then cloned and sequenced. The sequence showed no perfect match to any kno...
Micronutrient malnutrition is one of the major concerns noted in the United Nations Sustainable D... more Micronutrient malnutrition is one of the major concerns noted in the United Nations Sustainable Development Goals. In developing countries, children under the age of five and pregnant women are at the highest risk of adverse events from micronutrient malnutrition. Staple food crops that are common in developing countries are rich in carbohydrates but low in micronutrients, especially iron. Genetic biofortification of staple food crops in farmer-preferred cultivars is a promising approach to deliver nutritious food, enhanced in iron concentration, to consumers who are at risk of malnutrition. In order to achieve biofortification, it is critical to understand the processes of iron uptake, regulation, transport dynamics, and whole-plant iron storage and how to manipulate them in individual crops. In this review, case studies of staple food crops including rice, wheat, and cassava are used to introduce iron biofortification strategies in both monocotyledonous and dicotyledonous species,...
Micronutrient malnutrition is one of the major concerns noted in the United Nations Sustainable D... more Micronutrient malnutrition is one of the major concerns noted in the United Nations Sustainable Development Goals. In developing countries, children under the age of five and pregnant women are at the highest risk of adverse events from micronutrient malnutrition. Staple food crops that are common in developing countries are rich in carbohydrates but low in micronutrients, especially iron. Genetic biofortification of staple food crops in farmer-preferred cultivars is a promising approach to deliver nutritious food, enhanced in iron concentration, to consumers who are at risk of malnutrition. In order to achieve biofortification, it is critical to understand the processes of iron uptake, regulation, transport dynamics, and whole-plant iron storage and how to manipulate them in individual crops. In this review, case studies of staple food crops including rice, wheat, and cassava are used to introduce iron biofortification strategies in both monocotyledonous and dicotyledonous species, along with a discussion of consumer-based considerations for the deployment of biofortified crops also presented.
Turkish Journal of Agriculture - Food Science and Technology, 2021
Iron (Fe) deficiency in plants is one of the widespread problems limiting agricultural production... more Iron (Fe) deficiency in plants is one of the widespread problems limiting agricultural production. Generating crops more tolerant to Fe deficiency by genetic engineering or breeding is of great interest but challenging due to the knowledge gaps in general plant Fe homeostasis. Although several genes involved in Fe homeostasis have been identified, characterization of their roles is mainly limited to specific organs at specific developmental stages of the plant, where their mutants show the most striking phenotype. Vacuolar Iron Transporter 1 (VIT1) is a well-known gene that has been characterized for its function in the mature seed of Arabidopsis thaliana. VIT1 is an Fe transporter that determines the correct distribution of Fe storage in this organ. The study aimed to explore new physiological functions for VIT1. As a first step, Arabidopsis thaliana plants that contain PromoterVIT1: GUS constructs were used to study the temporal and spatial expression of the gene throughout the pl...
Um Gene zu identifizieren, die an der Toleranz gegenüber Fe-Mangel-induzierter Chlorose in Pflanz... more Um Gene zu identifizieren, die an der Toleranz gegenüber Fe-Mangel-induzierter Chlorose in Pflanzen beteiligt sind, wurden T-DNA-Insertionslinien von Arabidopsis auf einem Agarnährmedium mit hohem pH-Wert bei niedriger Fe-Verfügbarkeit angezogen. Dieser vorwärts gerichtete Ansatz führte zur Identifizierung von zwei Mutanten, die einen Defekt in der Genexpression für MTP8 aufwiesen und eine starke durch Fe-Mangel induzierte Chlorose entwickelten. MTP8 kodiert für einen Tonoplasten-lokalisierten Mn-Transporter, der unter Fe-Mangel hochreguliert wird. Der chlorotische Phenotyp der mtp8-Mutante konnte durch eine Blattdüngung mit Fe wie auch durch Ausschluss von Mn aus dem Nährmedium revertiert werden, was darauf hindeutete, dass Fe-Mangel durch Mn verursacht wurde. Da Fe-defiziente Pflanzen unter Fe-Mangel einen Überschuss an Mn aufnehmen, wird MTP8 für die Sequestrierung von Mnin die Vakuole benötigt, das anderenfalls die Reduktion von Fe vor der Aufnahme inhibiert. Darüber hinaus wurd...
Iron (Fe) deficiency is a widespread nutritional disorder on calcareous soils. To identify genes ... more Iron (Fe) deficiency is a widespread nutritional disorder on calcareous soils. To identify genes involved in the Fe deficiency response, Arabidopsis (Arabidopsis thaliana) transfer DNA insertion lines were screened on a high-pH medium with low Fe availability. This approach identified METAL TOLERANCE PROTEIN8 (MTP8), a member of the Cation Diffusion Facilitator family, as a critical determinant for the tolerance to Fe deficiency-induced chlorosis, also on soil substrate. Subcellular localization to the tonoplast, complementation of a manganese (Mn)-sensitive Saccharomyces cerevisiae yeast strain, and Mn sensitivity of mtp8 knockout mutants characterized the protein as a vacuolar Mn transporter suitable to prevent plant cells from Mn toxicity. MTP8 expression was strongly induced on low-Fe as well as high-Mn medium, which were both strictly dependent on the transcription factor FIT, indicating that high-Mn stress induces Fe deficiency. mtp8 mutants were only hypersensitive to Fe deficiency when Mn was present in the medium, which further suggested an Mn-specific role of MTP8 during Fe limitation. Under those conditions, mtp8 mutants not only translocated more Mn to the shoot than did wild-type plants but suffered in particular from critically low Fe concentrations and, hence, Fe chlorosis, although the transcriptional Fe deficiency response was up-regulated more strongly in mtp8. The diminished uptake of Fe from Mn-containing low-Fe medium by mtp8 mutants was caused by an impaired ability to boost the ferric chelate reductase activity, which is an essential process in Fe acquisition. These findings provide a mechanistic explanation for the long-known interference of Mn in Fe nutrition and define the molecular processes by which plants alleviate this antagonism.
Abstract Healthy plant growth depends on a balanced metal homeostasis at the organ, tissue and su... more Abstract Healthy plant growth depends on a balanced metal homeostasis at the organ, tissue and sub-cellular levels, which is mediated principally by plasma and vacuolar membrane metal transporters. The genetic bases of metal acquisition in developing seeds has long remained poorly understood. Recent technical advances have helped circumvent the difficulties of conducting metal nutrient research on the extremely small seeds of Arabidopsis thaliana . The review presents recent advances in our understanding of seed metal homeostasis focussing on this model plant. Metals are loaded from phloem to the seed coat and must pass through the endosperm to reach the embryo. The embryo comprises several apoplastic and symplastic pathways that strictly depend on the changing physiology of the developing seed organs. Metals that reach the developing embryo fuel immediate cellular processes or accumulate in vacuoles to support forthcoming germination. In the mature embryo, metal distribution is homogeneous, with the exception of iron and manganese which localize to distinct cell layers. These metal localizations are strictly dependent on expression of specific tonoplast transporters, with putative functions that go beyond the storage of metals. Accumulating evidence indicates that they can control the timing of metal entry into the embryo.
In plant cells, either excess or insufficient iron (Fe) concentration triggers stress responses, ... more In plant cells, either excess or insufficient iron (Fe) concentration triggers stress responses, therefore it is strictly controlled. Proteasome-mediated degradation through ubiquitination of Fe homeostasis proteins has just become the focus of research in recent years. Deactivating ubiquitin ligases, COP9 signalosome has a central importance in the translational control of various stress responses. The aim of the study was to investigate COP9 signalosome in Fe deficiency response of Strategy I plants. In silico analysis of a set of Fe-deficiency-responsive genes was conducted against the transcriptome of Arabidopsis csn mutant lines using Genevestigator software. Induced and suppressed genes were clustered in a hierarchical way and gene ontology enrichment categories were identified. In wild-type Arabidopsis, CSN genes did not respond to iron deficiency. In csn mutant lines, under Fe-sufficient conditions, hundreds of Fe-deficiency-responsive genes were misregulated. Among the ones previously characterized for their physiological roles under Fe deficiency IRT1, NAS4, BTS, NRAMP1 were down-regulated while AHA2, MTP8, FRD3 were up-regulated. Unexpectedly, from those which were regulated in opposite ways, some had been repeatedly shown to be tightly co-regulated by the same transcription factor, FIT. Two proteins from DELLA family, which were reported to interact with FIT to repress its downstream, were found to be strikingly repressed in csn mutants. Overall, the study underlined that the absence of a functional CSN greatly impacted the regulation of Fe homeostasis-related genes, in a manner which cannot be explained simply by the induction of the master transcription factor, FIT. Correct expression of Fe deficiency-responsive genes requires an intact COP9 signalosome in Arabidopsis.
Manufacturing high-profit goods in the information and technology age requires solid foundations ... more Manufacturing high-profit goods in the information and technology age requires solid foundations in basic sciences. However, despite their interests and high success, basic sciences often fail to attract university candidates due to the perceived job insecurity after graduation. To challenge this notion, the current study aimed to examine biology graduates’ profiles and career life. As a survey study, an online questionnaire was administered to 56 graduates of the biological sciences department. The findings showed that almost all graduates chose biology due to their interest in the first place. The majority thought that their undergraduate education prepared them effectively for their future career, and they acquired 21st-century skills adequately, except for entrepreneurship skills. They found a job related to their major in one to two years. They were primarily employed in universities and got academic positions. They were satisfied with their jobs. The study concluded that highe...
Background and purpose: Synthetic fertilizers damage the environment. Biofertilizers that consist... more Background and purpose: Synthetic fertilizers damage the environment. Biofertilizers that consist of microorganisms emerge as an environmentally friendly alternative. Biofertilizers improve plant growth by mobilizing soil nutrients, triggering plant hormone synthesis, or competing with pathogenic bacteria. However, biofertilizers often fail due to insufficient colonization of the plant roots.Materials and methods: To explore the colonization dynamics of a bacterial strain commonly used in biofertilizers, Bacillus subtilis OSU-142 (OSU-142), developing a set of primers specific to OSU-142 was aimed. Since its genome is unknown, to identify genomic regions unique to OSU-142 strain, DNAs of more than 40 bacterial strains were fingerprinted, most of which belong to Bacillus subtilis using the Randomly Amplified Polymorphic DNA (RAPD) method.Results: This approach identified a polymorphic band at 880 bp, which was then cloned and sequenced. The sequence showed no perfect match to any kno...
Micronutrient malnutrition is one of the major concerns noted in the United Nations Sustainable D... more Micronutrient malnutrition is one of the major concerns noted in the United Nations Sustainable Development Goals. In developing countries, children under the age of five and pregnant women are at the highest risk of adverse events from micronutrient malnutrition. Staple food crops that are common in developing countries are rich in carbohydrates but low in micronutrients, especially iron. Genetic biofortification of staple food crops in farmer-preferred cultivars is a promising approach to deliver nutritious food, enhanced in iron concentration, to consumers who are at risk of malnutrition. In order to achieve biofortification, it is critical to understand the processes of iron uptake, regulation, transport dynamics, and whole-plant iron storage and how to manipulate them in individual crops. In this review, case studies of staple food crops including rice, wheat, and cassava are used to introduce iron biofortification strategies in both monocotyledonous and dicotyledonous species,...
Micronutrient malnutrition is one of the major concerns noted in the United Nations Sustainable D... more Micronutrient malnutrition is one of the major concerns noted in the United Nations Sustainable Development Goals. In developing countries, children under the age of five and pregnant women are at the highest risk of adverse events from micronutrient malnutrition. Staple food crops that are common in developing countries are rich in carbohydrates but low in micronutrients, especially iron. Genetic biofortification of staple food crops in farmer-preferred cultivars is a promising approach to deliver nutritious food, enhanced in iron concentration, to consumers who are at risk of malnutrition. In order to achieve biofortification, it is critical to understand the processes of iron uptake, regulation, transport dynamics, and whole-plant iron storage and how to manipulate them in individual crops. In this review, case studies of staple food crops including rice, wheat, and cassava are used to introduce iron biofortification strategies in both monocotyledonous and dicotyledonous species, along with a discussion of consumer-based considerations for the deployment of biofortified crops also presented.
Turkish Journal of Agriculture - Food Science and Technology, 2021
Iron (Fe) deficiency in plants is one of the widespread problems limiting agricultural production... more Iron (Fe) deficiency in plants is one of the widespread problems limiting agricultural production. Generating crops more tolerant to Fe deficiency by genetic engineering or breeding is of great interest but challenging due to the knowledge gaps in general plant Fe homeostasis. Although several genes involved in Fe homeostasis have been identified, characterization of their roles is mainly limited to specific organs at specific developmental stages of the plant, where their mutants show the most striking phenotype. Vacuolar Iron Transporter 1 (VIT1) is a well-known gene that has been characterized for its function in the mature seed of Arabidopsis thaliana. VIT1 is an Fe transporter that determines the correct distribution of Fe storage in this organ. The study aimed to explore new physiological functions for VIT1. As a first step, Arabidopsis thaliana plants that contain PromoterVIT1: GUS constructs were used to study the temporal and spatial expression of the gene throughout the pl...
Um Gene zu identifizieren, die an der Toleranz gegenüber Fe-Mangel-induzierter Chlorose in Pflanz... more Um Gene zu identifizieren, die an der Toleranz gegenüber Fe-Mangel-induzierter Chlorose in Pflanzen beteiligt sind, wurden T-DNA-Insertionslinien von Arabidopsis auf einem Agarnährmedium mit hohem pH-Wert bei niedriger Fe-Verfügbarkeit angezogen. Dieser vorwärts gerichtete Ansatz führte zur Identifizierung von zwei Mutanten, die einen Defekt in der Genexpression für MTP8 aufwiesen und eine starke durch Fe-Mangel induzierte Chlorose entwickelten. MTP8 kodiert für einen Tonoplasten-lokalisierten Mn-Transporter, der unter Fe-Mangel hochreguliert wird. Der chlorotische Phenotyp der mtp8-Mutante konnte durch eine Blattdüngung mit Fe wie auch durch Ausschluss von Mn aus dem Nährmedium revertiert werden, was darauf hindeutete, dass Fe-Mangel durch Mn verursacht wurde. Da Fe-defiziente Pflanzen unter Fe-Mangel einen Überschuss an Mn aufnehmen, wird MTP8 für die Sequestrierung von Mnin die Vakuole benötigt, das anderenfalls die Reduktion von Fe vor der Aufnahme inhibiert. Darüber hinaus wurd...
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