To elucidate the current status of hip fracture incidence and treatment in Japan, a tally of hip ... more To elucidate the current status of hip fracture incidence and treatment in Japan, a tally of hip fractures in patients from 1998 to 2000 was conducted in Japanese Orthopaedic Association-related hospitals. Response rates were from 40.5% to 55.6% in each observation year. The survey found a total of 110 747 new hip fractures aged 35 years old and over during the survey years. Age- and gender-specific number of patients increased with age and peaked at the age of 80–84 years, then leveled off after 85 years of age. The number of patients with femoral neck fractures exceeded that with trochanteric fractures before 75 years of age, and these figures became inverted thereafter. More left hips were fractured than right in all survey years; however, the difference was not significant. The most common cause of hip fractures was a simple fall; 68.8% sustained fractures indoors, and there was a significant monthly variation. Ninety-three percent of the patients with femoral neck fractures and...
The aim of this study was to assess the effectiveness of the unipedal standing balance exercise f... more The aim of this study was to assess the effectiveness of the unipedal standing balance exercise for 1 min to prevent falls and hip fractures in high-risk elderly individuals with a randomized controlled trial. This control study was designed as a 6-month intervention trial. Subjects included 553 clinically defined high-risk adults who were living in residences or in the community. They were randomized to an exercise group and a control group. Randomization to the subjects was performed by a table of random numbers. A unipedal standing balance exercise with open eyes was performed by standing on each leg for 1 min three times per day. As a rule, subjects of the exercise group stood on one leg without holding onto any support, but unstable subjects were permitted to hold onto a bar during the exercise time. Falls and hip fractures were reported by nurses, physical therapists, or facility staff with a survey sheet every month. This survey sheet was required every month for both groups....
The aim of this study was to assess the disability and mortality of hip fractures 1 year after in... more The aim of this study was to assess the disability and mortality of hip fractures 1 year after initial visit (postoperatively) at fixed-point hospitals selected by the Japanese Orthopaedic Association Committee on Osteoporosis. A total of 158 core orthopedic hospitals were selected for participation in this research. Subjects were all aged 65 years and older with hip fractures at the selected hospitals between January 1, 1999 and December 31, 2001. A prognostic survey of activities of daily living (ADL), assessed by the long-term care insurance criteria established by the Ministry of Health, Labour, and Welfare of Japan was performed 1 year after the initial visit. A total of 1992 hip fractures in patients aged 65 to 111 years were treated over the 3 years from 1999 to 2001. Among the 1992 patients, 4537 had femoral neck fractures and 6217 had trochanteric fractures. Surgical treatment was chosen for 85.6% of the femoral neck fractures and 88.2% of the trochanteric fractures. The me...
To elucidate the characteristics of hip fractures and the current status of their treatment in Ja... more To elucidate the characteristics of hip fractures and the current status of their treatment in Japan, the Japanese Orthopaedic Association (JOA) conducted a nationwide hip fracture survey from 1998 to the present. The aim of the current report was to present the changes in patient distribution by age and fracture type, cause of fracture, treatment selection, and duration of hospitalization for a study period of one decade. A tally of all hip fractures that occurred in patients between 2001 and 2008 was conducted in JOA-authorized hospitals and in Japanese Clinical Orthopaedic Association (JCOA) hospitals. Registration forms were sent to these hospitals each year, and registration was performed based on their hospital records. The mean response rate was 51.8%, and the total number of patients aged ≥35 with new hip fractures between 2001 and 2008 was 402 760. A drastic increase in the number of patients, especially those aged ≥90 was observed over the course of the decade. More trocha...
Communications in Soil Science and Plant Analysis, 2003
The distribution and chemical forms of aluminum (Al) were determined in the roots of the Al-toler... more The distribution and chemical forms of aluminum (Al) were determined in the roots of the Al-tolerant rice cultivar Arkansas cultured in the presence of Al after being precultured with or without phosphates. Lumogallion staining was used to locate Al, and the highest levels of Al were found in the root cap of the plants precultured with phosphates. High levels of
The acidophilic and thermophilic unicellular red alga, Cyanidium caldarium (Tilden) Geitler, is w... more The acidophilic and thermophilic unicellular red alga, Cyanidium caldarium (Tilden) Geitler, is widely distributed in acidic hot springs. Observation by transmission electron microscopy (TEM) showed that algae grown in Allen's medium contained electron-dense bodies with diameters from 100 to 200 nm. Electron dispersive x-ray analysis indicated that the electron-dense bodies contained high levels of iron, phosphorous, and oxygen; P/Fe ratios were
There is anecdotal evidence that bone strains may increase to the point that bone becomes suscept... more There is anecdotal evidence that bone strains may increase to the point that bone becomes susceptible to rapid failure when muscles become fatigued. To determine whether neuromuscular response could be a factor in accelerating bone failure, we tested the hypothesis that muscle fatigue causes a significant increase in peak principal and shear strains in bone. Ten adult foxhounds were subjected to rigorous exercise that caused muscular fatigue while myoelectrical activity of the quadriceps and hamstrings and strain on the distal tibia were monitored simultaneously. Ground reaction forces on the dog hindlimbs were measured before and after strain gauges had been applied to the tibia. The data show a significant shift to lower median myoelectrical frequencies in the quadriceps, indicating muscular fatigue, following the 20 min exercise period. In conjunction with this shift, peak principal and shear strains increased on both compressive and tensile cortices of the tibia and shear strain...
Summary Seven kinds of suspension cell cultures from five species ofNicotiana were screened for t... more Summary Seven kinds of suspension cell cultures from five species ofNicotiana were screened for the occurrence of nicotianamine. Nicotianamine was detected in the cultured cells ofN. megalosiphon andN. plumbaginifolia.l-[l-14C]Methionine, which is the precursor of the mugineic-acid-family phytosiderophores and nicotianamine in barley plants, was incorporated into nicotianamine by the cultured cells ofN. megalosiphon both in vivo and in vitro. The advantage
Until now, the real-time uptake and movement of manganese (Mn), an essential plant nutrient, has ... more Until now, the real-time uptake and movement of manganese (Mn), an essential plant nutrient, has not been documented in plants. In this study, the real-time translocation of Mn in barley (Hordeum vulgare L. cv. Ehimehadaka no. 1) was visualized using the positron-emitting tracer Mn and a positron-emitting tracer imaging system (PETIS). PETIS allowed the non-destructive monitoring of Mn translocation in
A bromine-81 NMR study was conducted to characterize the Cl-binding site of porcine pancreatic α-... more A bromine-81 NMR study was conducted to characterize the Cl-binding site of porcine pancreatic α-amylase. Only a single signal was observed in the spectrum in the presence of an equimolar concentration of the enzyme and NaBr. the signal was assigned to free Br ions, which are in very slow exchange with the protein-bound Br on an NMR time scale. the presence of a common anion-binding site was demonstrated from the competition of Br with F, Cl, NO 3, and ClO 4 for the site.
Abstract 15P-water flow from the roots to the top in tomato (Lycopersicon esculentum Mill.) and r... more Abstract 15P-water flow from the roots to the top in tomato (Lycopersicon esculentum Mill.) and rice (Oryza sativa L.) plants was visualized with time using a positron-emitting tracer imaging system (PETIS). The 15O-water flow was switched on by light and completely ...
Acetabular dysplasia (AD) is the main cause of hip osteoarthritis in Japan. A simple method to ev... more Acetabular dysplasia (AD) is the main cause of hip osteoarthritis in Japan. A simple method to evaluate acetabular dysplasia would be helpful for early treatment or prevention of hip osteoarthritis. Acetabular dysplasia is reported to be associated with pathological transverse growth of the pelvis, indicating that the distance between the 2 anterior superior iliac spines might be useful for screening and detection of acetabular dysplasia. The purpose of this study was to determine if the acetabular dysplasia radiographic parameters are related to the distance between the 2 anterior superior iliac spines in patients with hip osteoarthritis. In this study, data obtained in a previous multi-institutional examination of patients with hip osteoarthritis in Japan were evaluated. The anterior superior iliac spine distances of 176 female patients (mean age, 54 years; range, 18-85 years) were measured by physical examination. The relationship between the anterior superior iliac spine distance and acetabular dysplasia was analyzed, and the anterior superior iliac spine distances of the patients with acetabular dysplasia who were at relatively high risk for hip osteoarthritis were compared with that of the patients at lower risk. A statistically significant relationship between the anterior superior iliac spine distance and all of the acetabular dysplasia parameters was observed. The anterior superior iliac spine distances of the acetabular dysplasia patients with a relatively high risk for radiographic acetabular dysplasia parameters were significantly smaller than those of patients at lower risk. Even after adjustment for age, height, and weight, significantly increased relative risk for having high risk AD was found in patients with an ASIS distance of less than 24.5 cm. There was a significant relationship between the anterior superior iliac spine distance and the degree of acetabular dysplasia.
We first demonstrate a field-effect-transistor operation of dimetallofullerene La2@C80 with the i... more We first demonstrate a field-effect-transistor operation of dimetallofullerene La2@C80 with the icosahedral cage symmetry. The thin-film device showed an n-type behavior with a mobility of 1.1 x 10-4 cm2/V s at room temperature under high vacuum. Taking the nature of LUMO into account, the n-type behavior indicates an occurrence of carrier conduction through encapsulated La ions. The low mobility, suggesting an intermolecular hopping mechanism, is ascribed to the intrinsic and extrinsic reasons, which are discussed in the text.
... 1996); in addition, the molecular weights of SAM synthetases calculated from cDNAs of barley ... more ... 1996); in addition, the molecular weights of SAM synthetases calculated from cDNAs of barley obtained by our laboratory were found to be around 28 kDa (accession numbers of sam1, sam2 and sam3 are D63835, D85238 and D85237, respectively), and their pI values were ...
Concurrent treatments with bisphosphonates and vitamin K are promising given that bisphosphonates... more Concurrent treatments with bisphosphonates and vitamin K are promising given that bisphosphonates possibly interfere with vitamin K activation. This is a prospective, multi-center, open-labeled, randomized trial of the efficacy of concurrent treatment with vitamin K2 and risedronate compared with risedronate alone and to explore subsets of patients for which concurrent treatment is particularly efficacious (trial identification number UMIN000000991). Inclusion criteria are women who meet the criteria for pharmacological therapy for osteoporosis, aged ≥65 years, have any of pre-specified risk factors, can walk unassisted, and are able to answer questionnaires. Exclusion criteria are prior warfarin use, secondary osteoporosis or non-osteoporotic metabolic bone diseases, contraindication for vitamin K2 and risedronate, hyper- or hypoparathyroidism, mental disorders, prevalent vertebral fracture at ≥6 sites, severe degenerative spinal deformation between T4 and L4, serious heart, liver, or kidney disease, or bisphosphonate use within the previous 6 months. Patients were recruited from 123 institutes between January 2008 and February 2010, and allocated to vitamin K2 (45 mg/day) and risedronate (2.5 mg/day or 17.5 mg/week) or risedronate alone (2.5 mg/day or 17.5 mg/week) groups. Primary endpoint is a vertebral or non-vertebral fracture. Secondary endpoints are bone mineral density, height, undercarboxylated osteocalcin, JOQOL, EQ-5D and safety. A sample size of 910 subjects per group and 2-year follow-up will provide 80 % power to detect 35 % risk reduction for fracture, with a two-sided significance level of 5 %. Subgroup analysis stratified to adjustment factors for random allocation, body mass index, 25-hydroxyvitamin D, estimated glomerular filtration rate, grade of vertebral fracture, JOQOL, EQ-5D, and co-morbidity is pre-specified.
Graminaceous plants take up iron through YS1 (yellow stripe 1) and YS1-like (YSL) transporters us... more Graminaceous plants take up iron through YS1 (yellow stripe 1) and YS1-like (YSL) transporters using iron-chelating compounds known as mugineic acid family phytosiderophores. We examined the expression of 18 rice (Oryza sativa L.) YSL genes (OsYSL1-18) in the epidermis/exodermis, cortex, and stele of rice roots. Expression of OsYSL15 in root epidermis and stele was induced by iron deficiency and showed daily fluctuation. OsYSL15 restored a yeast mutant defective in iron uptake when supplied with iron(III)-deoxymugineic acid and transported iron(III)-deoxymugineic acid in Xenopus laevis oocytes. An OsYSL15-green fluorescent protein fusion was localized to the plasma membrane when transiently expressed in onion epidermal cells. OsYSL15 promoter-beta-glucuronidase analysis revealed that OsYSL15 expression in roots was dominant in the epidermis/exodermis and phloem cells under conditions of iron deficiency and was detected only in phloem under iron sufficiency. These results strongly suggest that OsYSL15 is the dominant iron(III)-deoxymugineic acid transporter responsible for iron uptake from the rhizosphere and is also responsible for phloem transport of iron. OsYSL15 was also expressed in flowers, developing seeds, and in the embryonic scutellar epithelial cells during seed germination. OsYSL15 knockdown seedlings showed severe arrest in germination and early growth and were rescued by high iron supply. These results demonstrate that rice OsYSL15 plays a crucial role in iron homeostasis during the early stages of growth.
To elucidate the current status of hip fracture incidence and treatment in Japan, a tally of hip ... more To elucidate the current status of hip fracture incidence and treatment in Japan, a tally of hip fractures in patients from 1998 to 2000 was conducted in Japanese Orthopaedic Association-related hospitals. Response rates were from 40.5% to 55.6% in each observation year. The survey found a total of 110 747 new hip fractures aged 35 years old and over during the survey years. Age- and gender-specific number of patients increased with age and peaked at the age of 80–84 years, then leveled off after 85 years of age. The number of patients with femoral neck fractures exceeded that with trochanteric fractures before 75 years of age, and these figures became inverted thereafter. More left hips were fractured than right in all survey years; however, the difference was not significant. The most common cause of hip fractures was a simple fall; 68.8% sustained fractures indoors, and there was a significant monthly variation. Ninety-three percent of the patients with femoral neck fractures and...
The aim of this study was to assess the effectiveness of the unipedal standing balance exercise f... more The aim of this study was to assess the effectiveness of the unipedal standing balance exercise for 1 min to prevent falls and hip fractures in high-risk elderly individuals with a randomized controlled trial. This control study was designed as a 6-month intervention trial. Subjects included 553 clinically defined high-risk adults who were living in residences or in the community. They were randomized to an exercise group and a control group. Randomization to the subjects was performed by a table of random numbers. A unipedal standing balance exercise with open eyes was performed by standing on each leg for 1 min three times per day. As a rule, subjects of the exercise group stood on one leg without holding onto any support, but unstable subjects were permitted to hold onto a bar during the exercise time. Falls and hip fractures were reported by nurses, physical therapists, or facility staff with a survey sheet every month. This survey sheet was required every month for both groups....
The aim of this study was to assess the disability and mortality of hip fractures 1 year after in... more The aim of this study was to assess the disability and mortality of hip fractures 1 year after initial visit (postoperatively) at fixed-point hospitals selected by the Japanese Orthopaedic Association Committee on Osteoporosis. A total of 158 core orthopedic hospitals were selected for participation in this research. Subjects were all aged 65 years and older with hip fractures at the selected hospitals between January 1, 1999 and December 31, 2001. A prognostic survey of activities of daily living (ADL), assessed by the long-term care insurance criteria established by the Ministry of Health, Labour, and Welfare of Japan was performed 1 year after the initial visit. A total of 1992 hip fractures in patients aged 65 to 111 years were treated over the 3 years from 1999 to 2001. Among the 1992 patients, 4537 had femoral neck fractures and 6217 had trochanteric fractures. Surgical treatment was chosen for 85.6% of the femoral neck fractures and 88.2% of the trochanteric fractures. The me...
To elucidate the characteristics of hip fractures and the current status of their treatment in Ja... more To elucidate the characteristics of hip fractures and the current status of their treatment in Japan, the Japanese Orthopaedic Association (JOA) conducted a nationwide hip fracture survey from 1998 to the present. The aim of the current report was to present the changes in patient distribution by age and fracture type, cause of fracture, treatment selection, and duration of hospitalization for a study period of one decade. A tally of all hip fractures that occurred in patients between 2001 and 2008 was conducted in JOA-authorized hospitals and in Japanese Clinical Orthopaedic Association (JCOA) hospitals. Registration forms were sent to these hospitals each year, and registration was performed based on their hospital records. The mean response rate was 51.8%, and the total number of patients aged ≥35 with new hip fractures between 2001 and 2008 was 402 760. A drastic increase in the number of patients, especially those aged ≥90 was observed over the course of the decade. More trocha...
Communications in Soil Science and Plant Analysis, 2003
The distribution and chemical forms of aluminum (Al) were determined in the roots of the Al-toler... more The distribution and chemical forms of aluminum (Al) were determined in the roots of the Al-tolerant rice cultivar Arkansas cultured in the presence of Al after being precultured with or without phosphates. Lumogallion staining was used to locate Al, and the highest levels of Al were found in the root cap of the plants precultured with phosphates. High levels of
The acidophilic and thermophilic unicellular red alga, Cyanidium caldarium (Tilden) Geitler, is w... more The acidophilic and thermophilic unicellular red alga, Cyanidium caldarium (Tilden) Geitler, is widely distributed in acidic hot springs. Observation by transmission electron microscopy (TEM) showed that algae grown in Allen's medium contained electron-dense bodies with diameters from 100 to 200 nm. Electron dispersive x-ray analysis indicated that the electron-dense bodies contained high levels of iron, phosphorous, and oxygen; P/Fe ratios were
There is anecdotal evidence that bone strains may increase to the point that bone becomes suscept... more There is anecdotal evidence that bone strains may increase to the point that bone becomes susceptible to rapid failure when muscles become fatigued. To determine whether neuromuscular response could be a factor in accelerating bone failure, we tested the hypothesis that muscle fatigue causes a significant increase in peak principal and shear strains in bone. Ten adult foxhounds were subjected to rigorous exercise that caused muscular fatigue while myoelectrical activity of the quadriceps and hamstrings and strain on the distal tibia were monitored simultaneously. Ground reaction forces on the dog hindlimbs were measured before and after strain gauges had been applied to the tibia. The data show a significant shift to lower median myoelectrical frequencies in the quadriceps, indicating muscular fatigue, following the 20 min exercise period. In conjunction with this shift, peak principal and shear strains increased on both compressive and tensile cortices of the tibia and shear strain...
Summary Seven kinds of suspension cell cultures from five species ofNicotiana were screened for t... more Summary Seven kinds of suspension cell cultures from five species ofNicotiana were screened for the occurrence of nicotianamine. Nicotianamine was detected in the cultured cells ofN. megalosiphon andN. plumbaginifolia.l-[l-14C]Methionine, which is the precursor of the mugineic-acid-family phytosiderophores and nicotianamine in barley plants, was incorporated into nicotianamine by the cultured cells ofN. megalosiphon both in vivo and in vitro. The advantage
Until now, the real-time uptake and movement of manganese (Mn), an essential plant nutrient, has ... more Until now, the real-time uptake and movement of manganese (Mn), an essential plant nutrient, has not been documented in plants. In this study, the real-time translocation of Mn in barley (Hordeum vulgare L. cv. Ehimehadaka no. 1) was visualized using the positron-emitting tracer Mn and a positron-emitting tracer imaging system (PETIS). PETIS allowed the non-destructive monitoring of Mn translocation in
A bromine-81 NMR study was conducted to characterize the Cl-binding site of porcine pancreatic α-... more A bromine-81 NMR study was conducted to characterize the Cl-binding site of porcine pancreatic α-amylase. Only a single signal was observed in the spectrum in the presence of an equimolar concentration of the enzyme and NaBr. the signal was assigned to free Br ions, which are in very slow exchange with the protein-bound Br on an NMR time scale. the presence of a common anion-binding site was demonstrated from the competition of Br with F, Cl, NO 3, and ClO 4 for the site.
Abstract 15P-water flow from the roots to the top in tomato (Lycopersicon esculentum Mill.) and r... more Abstract 15P-water flow from the roots to the top in tomato (Lycopersicon esculentum Mill.) and rice (Oryza sativa L.) plants was visualized with time using a positron-emitting tracer imaging system (PETIS). The 15O-water flow was switched on by light and completely ...
Acetabular dysplasia (AD) is the main cause of hip osteoarthritis in Japan. A simple method to ev... more Acetabular dysplasia (AD) is the main cause of hip osteoarthritis in Japan. A simple method to evaluate acetabular dysplasia would be helpful for early treatment or prevention of hip osteoarthritis. Acetabular dysplasia is reported to be associated with pathological transverse growth of the pelvis, indicating that the distance between the 2 anterior superior iliac spines might be useful for screening and detection of acetabular dysplasia. The purpose of this study was to determine if the acetabular dysplasia radiographic parameters are related to the distance between the 2 anterior superior iliac spines in patients with hip osteoarthritis. In this study, data obtained in a previous multi-institutional examination of patients with hip osteoarthritis in Japan were evaluated. The anterior superior iliac spine distances of 176 female patients (mean age, 54 years; range, 18-85 years) were measured by physical examination. The relationship between the anterior superior iliac spine distance and acetabular dysplasia was analyzed, and the anterior superior iliac spine distances of the patients with acetabular dysplasia who were at relatively high risk for hip osteoarthritis were compared with that of the patients at lower risk. A statistically significant relationship between the anterior superior iliac spine distance and all of the acetabular dysplasia parameters was observed. The anterior superior iliac spine distances of the acetabular dysplasia patients with a relatively high risk for radiographic acetabular dysplasia parameters were significantly smaller than those of patients at lower risk. Even after adjustment for age, height, and weight, significantly increased relative risk for having high risk AD was found in patients with an ASIS distance of less than 24.5 cm. There was a significant relationship between the anterior superior iliac spine distance and the degree of acetabular dysplasia.
We first demonstrate a field-effect-transistor operation of dimetallofullerene La2@C80 with the i... more We first demonstrate a field-effect-transistor operation of dimetallofullerene La2@C80 with the icosahedral cage symmetry. The thin-film device showed an n-type behavior with a mobility of 1.1 x 10-4 cm2/V s at room temperature under high vacuum. Taking the nature of LUMO into account, the n-type behavior indicates an occurrence of carrier conduction through encapsulated La ions. The low mobility, suggesting an intermolecular hopping mechanism, is ascribed to the intrinsic and extrinsic reasons, which are discussed in the text.
... 1996); in addition, the molecular weights of SAM synthetases calculated from cDNAs of barley ... more ... 1996); in addition, the molecular weights of SAM synthetases calculated from cDNAs of barley obtained by our laboratory were found to be around 28 kDa (accession numbers of sam1, sam2 and sam3 are D63835, D85238 and D85237, respectively), and their pI values were ...
Concurrent treatments with bisphosphonates and vitamin K are promising given that bisphosphonates... more Concurrent treatments with bisphosphonates and vitamin K are promising given that bisphosphonates possibly interfere with vitamin K activation. This is a prospective, multi-center, open-labeled, randomized trial of the efficacy of concurrent treatment with vitamin K2 and risedronate compared with risedronate alone and to explore subsets of patients for which concurrent treatment is particularly efficacious (trial identification number UMIN000000991). Inclusion criteria are women who meet the criteria for pharmacological therapy for osteoporosis, aged ≥65 years, have any of pre-specified risk factors, can walk unassisted, and are able to answer questionnaires. Exclusion criteria are prior warfarin use, secondary osteoporosis or non-osteoporotic metabolic bone diseases, contraindication for vitamin K2 and risedronate, hyper- or hypoparathyroidism, mental disorders, prevalent vertebral fracture at ≥6 sites, severe degenerative spinal deformation between T4 and L4, serious heart, liver, or kidney disease, or bisphosphonate use within the previous 6 months. Patients were recruited from 123 institutes between January 2008 and February 2010, and allocated to vitamin K2 (45 mg/day) and risedronate (2.5 mg/day or 17.5 mg/week) or risedronate alone (2.5 mg/day or 17.5 mg/week) groups. Primary endpoint is a vertebral or non-vertebral fracture. Secondary endpoints are bone mineral density, height, undercarboxylated osteocalcin, JOQOL, EQ-5D and safety. A sample size of 910 subjects per group and 2-year follow-up will provide 80 % power to detect 35 % risk reduction for fracture, with a two-sided significance level of 5 %. Subgroup analysis stratified to adjustment factors for random allocation, body mass index, 25-hydroxyvitamin D, estimated glomerular filtration rate, grade of vertebral fracture, JOQOL, EQ-5D, and co-morbidity is pre-specified.
Graminaceous plants take up iron through YS1 (yellow stripe 1) and YS1-like (YSL) transporters us... more Graminaceous plants take up iron through YS1 (yellow stripe 1) and YS1-like (YSL) transporters using iron-chelating compounds known as mugineic acid family phytosiderophores. We examined the expression of 18 rice (Oryza sativa L.) YSL genes (OsYSL1-18) in the epidermis/exodermis, cortex, and stele of rice roots. Expression of OsYSL15 in root epidermis and stele was induced by iron deficiency and showed daily fluctuation. OsYSL15 restored a yeast mutant defective in iron uptake when supplied with iron(III)-deoxymugineic acid and transported iron(III)-deoxymugineic acid in Xenopus laevis oocytes. An OsYSL15-green fluorescent protein fusion was localized to the plasma membrane when transiently expressed in onion epidermal cells. OsYSL15 promoter-beta-glucuronidase analysis revealed that OsYSL15 expression in roots was dominant in the epidermis/exodermis and phloem cells under conditions of iron deficiency and was detected only in phloem under iron sufficiency. These results strongly suggest that OsYSL15 is the dominant iron(III)-deoxymugineic acid transporter responsible for iron uptake from the rhizosphere and is also responsible for phloem transport of iron. OsYSL15 was also expressed in flowers, developing seeds, and in the embryonic scutellar epithelial cells during seed germination. OsYSL15 knockdown seedlings showed severe arrest in germination and early growth and were rescued by high iron supply. These results demonstrate that rice OsYSL15 plays a crucial role in iron homeostasis during the early stages of growth.
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