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Makoto Yamamoto

Publications and source records attributed to Makoto Yamamoto.

At least 19 recordsLinked to original sources
PubMed2006

Application of TL as a geochemical sensor.

Two-dimensional thermoluminescence (TL) and spectroscopy of rock samples were measured to identify a mass transport front in rock matrix. Samples were selected from the Kamaishi Mine including the hydrothermal mineral veins and the surrounding altered zone. Results showed some different distribution of TL intensity between the altered and unaltered zones. Minerals in the altered zone showed stronger TL than those in the unaltered zone, and different phenomena for wavelength could be observed between them. Therefore, it could possibly be shown that TL can be used as a chemical sensor, which identifies mass change (transport front in rocks), by using these TL methods.

Dose-Response Relationship, Radiation↗
PubMed2006

A simple and efficient synthesis of puromycin, 2,2'-anhydro-pyrimidine nucleosides, cytidines and 2',3'-anhydroadenosine from 3',5'-O-sulfinyl xylo-nucleosides.

Synthesis of antibiotics, puromycin and 3'-amino-3'-deoxy-N6,N6-dimethyladenosine 11 was achieved by utilizing the cyclic sulfite 6a of the xylo-3',5'-dihydroxy group as a new protective group. The key synthetic step is the deprotection of the sulfite moiety through the intramolecular cyclization of 2-alpha-carbamate 7. In a similar manner 2,2'-anhydro-pyrimidine nucleosides 15, ribo-cytidines 17 and 2',3'-anhydroadenosine 14 were prepared in high yields from the corresponding sulfites 4, 5, and 6b, respectively.

Adenosine↗
PubMed2006

[Susceptibilities of bacteria isolated from patients with lower respiratory infectious diseases to antibiotics (2004)].

From October 2004 to September 2005, we collected the specimen from 319 patients with lower respiratory tract infections in 12 institutions in Japan, and investigated the susceptibilities of isolated bacteria to various antibacterial agents and patients' characteristics. Of 383 strains that were isolated from specimen (mainly from sputum) and assumed to be bacteria causing in inflammation, 381 strains were examined. The breakdown of the isolated bacteria were: Staphylococcus aureus 87, Streptococcus pneumoniae 80, Haemophilus influenzae 78, Pseudomonas aeruginosa (non-mucoid) 35, P. aeruginosa (mucoid) 9, Klebsiella pneumoniae 15, Moraxella subgenus Branhamella catarrhalis 30, etc. Of 87 S. aureus strains, those with 2 microg/mL or less of MIC of oxacillin (methicillin-sensitive S. aureus: MSSA) and those with 4 microg/mL or more of MIC of oxacillin (methicillin-resistant S. aureus: MRSA) were 40 (46.0%) and 47 (54.0%) strains, respectively. Against MSSA, imipenem had the most potent antibacterial activity and inhibited the growth of all the strains at 0.063 microg/mL. Against MRSA, vancomycin showed the most potent activity and inhibited the growth of all the strains at 1 microg/mL. Arbekacin (ABK) also showed the potent activity and its MIC90 was 2 microg/mL. Carbapenems showed the most potent activities against S. pneumoniae and inhibited the growth of all the strains at 0.25-0.5 microg/mL. Cefozopran (CZOP) also had a preferable activity (MIC90: 1 microg/mL) and inhibited the growth of all the strains at 2 microg/mL. In contrast, there were high-resistant strains (MIC: 128 microg/mL or more) for ABK (2.5%), erythromycin (37.5%), and clindamycin (38.8%). Against H. influenzae, levofloxacin showed the most potent activity and inhibited the growth of all the strains at 0.125 microg/mL. Meropenem showed the most potent activity against P. aeruginosa (mucoid) and inhibited the growth of all the strains at 2 microg/mL. Against P. aeruginosa (non-mucoid), amikacin (AMK) had the most potent activity and its MIC90 was 4 microg/mL. The activity of CZOP against the non-mucoid type also was preferable and its MIC90 was 8 microg/mL. Against K. pneumoniae, CZOP, cefmenoxime, cefpirome, flomoxef were the most potent activity and inhibited the growth of all the strains at 0.063 microg/mL. Also, all the agents generally showed a potent activity against M. (B.) catarrhalis and the MIC90 of them were 4 microg/mL or less. The approximately half the number (57.0%) of the patients with respiratory infection were aged 70 years or older. Bacterial pneumonia and chronic bronchitis accounted for 50.8% and 23.8% of all the respiratory infection, respectively. The bacteria frequently isolated from the patients with bacterial pneumonia were S. aureus (21.6%), S. pneumoniae (24.7%) and H. influenzae (20.1%). S. aureus (20.9%), S. pneumoniae (16.1%), and H. influenzae (16.1%) also were relatively frequently isolated from the patients with chronic bronchitis. Before the drug administration, the bacteria frequently isolated from the patients were S. pneumoniae (22.3%) and H. influenzae (25.1%). The bacteria relatively frequently isolated from the patients treated with macrolides were P. aeruginosa and the isolation frequency was 43.5%.

Aged↗
PubMed2005

Branching ducts similar to mesonephric ducts or ureteric buds in teratomas originating from mouse embryonic stem cells.

Ureteric bud epithelial cells and metanephric mesenchymal cells that comprise the metanephric kidney primordium are capable of producing nephrons and collecting ducts through reciprocal inductive interaction. Once these cells are induced from pluripotent embryonic stem (ES) cells, they have the potential to become powerful tools in the regeneration of kidney tissues. In this study, we investigated these renal primordial cells and structures in mouse ES cell outgrowths and their transplants. Gene expression essential for early kidney development was examined by RT-PCR in embryoid body (EB) outgrowths and their transplants in adult mice. Histochemical detection of kidney primordial structures and gene expression analysis coupled with laser microdissection were performed in transplant tissues. RT-PCR analysis detected gene expression of Pax-2, Lim-1, c-Ret, Emx2, Sall1, WT-1, Eya-1, GDNF, and Wnt-4 in the EB outgrowths from days 6-9 of expansion onward, and also in the teratoma tissues 14 and 28 days after transplantation. Histochemical analysis 14 days after transplantation showed that some ducts were positive for Pax-2, endo A cytokeratin, kidney-specific cadherin, and Dolichos biflorus agglutinin and that dichotomous branching of these ducts had occurred. These staining patterns and morphological features are intrinsic for mesonephric ducts and ureteric buds. In long-term survival of 28 days, Pax-2-immunoreactivity disappeared in some renal primordia-like structures, indicating their differentiation. Some ducts were accompanied by mesonephric nephron-like convoluted tubules. RT-PCR analysis of those structures collected by microdissection confirmed that they expressed kidney development-related genes. In conclusion, these data suggest the potential of ES cells to produce renal primordial duct structures and provides an insight into the regeneration of kidney tissues.

Animals↗
PubMed2005

A ferroelectrically switchable columnar liquid crystal phase with achiral molecules: superstructures and properties of liquid crystalline ureas.

Novel columnar liquid crystalline compounds N,N'-bis(3,4,5-trialkoxylphenyl)ureas 1a-c (R = n-C(8)H(17), n-C(12)H(25), and n-C(16)H(33)) were synthesized, and their phase transitions were measured by differential scanning calorimetery. The superstructures were investigated by X-ray diffraction, polarized light optical microscopy, and IR spectroscopy. The compounds exhibited both rectangular and hexagonal columnar phases in which the urea molecules in each column were stacked in one direction with strong hydrogen bonds. To confirm the ferroelectric switching, optoelectronic experiments were carried out, and the hexagonal columnar phases of 1b and 1c gave a sharp peak of spontaneous polarization in response to an applied triangular wave electric field (0.1-18 Hz). This is the first example of ferroelectrically switchable columnar liquid crystal phases generated by achiral molecules.

Journal Article↗
PubMed2005

Aromatic foldamers with iminodicarbonyl linkers: their structures and optical properties.

[structure: see text] Carboxamides possessing naphthalene rings connected by multiple iminodicarbonyl linkers were synthesized. These molecules forced the naphthalene rings to be placed in the positions facing each other, and they form helical foldamers both in solution and in the crystalline state. Their folding structures were investigated by single-crystal X-ray analysis and (1)H NMR spectroscopy. Their absorption and fluorescence spectra showed a red shift as the number of naphthalene moieties increased. This remarkable change is based on the intramolecular interaction between naphthalene moieties. Helicity of the foldamer can be controlled by the introduction of chiral auxiliaries at imide nitrogen atoms, which results in an observation of induced circular dichroism.

Journal Article↗
PubMed2005

From molecular footprints of disease to new therapeutic interventions in diabetic nephropathy.

Proteins are particularly attractive targets for product analysis, which is used to understand pathology. Protein modifications, such as advanced glycation end products (AGEs), serve as footprints of biochemical processes and also help in the search for novel agents that efficiently inhibit protein damage. Interestingly, several medical agents that are used clinically interfere with oxidative protein damage through different mechanisms characteristic of their chemical structures. We recently found that angiotensin II receptor blockers (ARBs) and angiotensin converting enzyme inhibitors (ACEIs) lower the in vitro formation of the AGEs pentosidine and carboxymethyllysine. Their inhibition for AGE formation is more striking than aminoguanidine. Unlike aminoguanidine, ARBs and ACEIs do not trap reactive carbonyl precursors of AGEs. Rather, they inhibit AGE formation, possibly as a result of their potent ability to scavenge hydroxyl radicals and to chelate the transition metals necessary for the Fenton reaction. We tested their AGE-lowering ability in vivo in a unique type-2 diabetic model with nephropathic SHR/NDmcr-cp rats, which exhibits the metabolic syndrome (obesity, hyperglycemia, hyperlipidemia, hyperinsulinemia) in addition to hypertension. Obesity and associated metabolic derangements, in addition to hypertension, markedly accelerate renal injury. Expectedly, correction of hyperglycemia and hyperinsulinemia partially but significantly improves renal injury. A low-calorie diet greatly improves renal injury despite persistent hypertension. Among antihypertensive agents, ARBs, unlike nifedipine and atenolol, are renoprotective despite persistent metabolic syndrome, but their action is independent of blood pressure lowering and is observed in a dose-dependent manner despite the complete blockade of angiotensin II receptor. Interestingly, the improvement of renal injury by ARBs as well as a low-calorie diet is associated with a significant reduction in local oxidative stress and AGE formation in the kidney. During the characterization of the AGE-lowering profile of our chemical compound libraries ( approximately 2000), we identified several inhibitors of oxidative stress and advanced glycation. They are indeed renoprotective, independently of correction of hypertension and metabolic syndrome, in experimental diabetic nephropathy and other nephritis models. Altogether, our data are in good agreement with the recent therapeutic concept for diabetic nephropathy that multiple risk factor interventions are critical in the treatment of diabetic renal injury, and further implicate a therapeutic potential of inhibition of oxidative stress and advanced glycation.

Animals↗
PubMed2005

Phenotype-specific cells with proliferative potential are produced by polyethylene glycol-induced fusion of mouse embryonic stem cells with fetal cardiomyocytes.

Because cardiomyocytes lose the ability to divide upon differentiation, myocardial failure is assumed to be generally irreversible. For terminal cardiac insufficiency, the potential for regenerative treatment by stem cells, especially embryonic stem (ES) cells, offers hope for the future. Recent studies showed that stem cells fuse spontaneously with cells remaining in damaged tissues, and restore tissue function. To imitate spontaneous fusion in vivo, we used polyethylene glycol (PEG) in vitro to fuse mouse ES cells and fetal cardiomyocytes and analyzed the cytochemical properties of the fused cells. Confocal laser scanning microscopy coupled with lipophilic dye labeling of the living cell membranes showed that there were fused cells of ES cells and cardiomyocytes after PEG treatment. By flow cytometry, the fusion efficiency between ES cells and cardiomyocytes was estimated to be about 45% of the total resulting cells. When green fluorescent protein (GFP)-expressing ES cells were fused with cardiomyocytes, the fused cells had immunoreactivity for GFP in their cytoplasm and cardiac troponin I in their myofibrils. Some of these cells also expressed proliferating cell nuclear antigen up to 11 days after fusion, the last time point examined. This study shows that PEG-induced fusions of mouse ES cells and cardiomyocytes have the cardiomyocyte phenotype and proliferation potential.

Animals↗
PubMed2005

[Susceptibilities of bacteria isolated from patients with lower respiratory infectious diseases to antibiotics (2003)].

From October 2003 to September 2004, we collected the specimen from 399 patients with lower respiratory tract infections in 12 institutions in Japan, and investigated the susceptibilities of isolated bacteria to various antibacterial agents and patients' characteristics. Of 474 strains that were isolated from specimen (mainly from sputum) and assumed to be bacteria causing in inflammation, 469 strains were examined. The breakdown of the isolated bacteria were: Staphylococcus aureus 76, Streptococcus pneumoniae 81, Haemophilus influenzae 84, Pseudomonas aeruginosa (non-mucoid) 56, P. aeruginosa (mucoid) 11, Klebsiella pneumoniae 36, Moraxella subgenus Branhamella catarrhalis 24, etc. Of 76 S. aureus strains, those with 2 microg/ml or less of MIC of oxacillin (methicillin-susceptible S. aureus: MSSA) and those with 4 microg/ml or more of MIC of oxacillin (methicillin-resistant S. aureus: MRSA) were both 38 strains (50.0%). Against MSSA, imipenem had the most potent antibacterial activity and inhibited the growth of all the strains at 0.063 microg/mL. Against MRSA, vancomycin showed the most potent activity and inhibited the growth of all the strains at 2 microg/mL. Arbekacin also showed the potent activity and inhibited the growth of all the strains at 4 microg/mL. Carbapenems showed the most potent activities against S. pneumoniae and inhibited the growth of all the strains at 0.125-0.5 microg/mL. Cefozopran (CZOP) also had a preferable activity (MIC90:2 microg/ mL) and inhibited the growth of all the strains at 4 microg/mL. In contrast, there were high-resistant strains (MIC: 128 microg/mL or more) for cefaclor (11.1%), erythromycin (43.2%), and clindamycin (40.7%). Against H. influenzae, levofloxacin showed the most potent activity and inhibited the growth of 83 of all the strains (98.8%) at 0.063 microg/mL. Tobramycin showed the most potent activity against P. aeruginosa (both mucoid and non-mucoid) and its MIC90 was 2 microg/mL. The activity of CZOP also was preferable and its MIC90 was 4 microg/mL for the mucoid-type and 8 microg/mL for the non-mucoid type. CZOP was the most potent activities against K. pneumoniae and inhibited the growth of all the strains at 0.125 microg/mL. Also, all the agents generally showed potent activities against M. (B.) catarrhalis and the MIC90 of them were 4 microg/mL or less. The approximately half the number (54.1%) of the patients with respiratory infection were aged 70 years or older. Bacterial pneumonia and chronic bronchitis accounted for 46.1% and 30.6% of all the respiratory infection, respectively. The bacteria frequently isolated from the patients with bacterial pneumonia were S. aureus (18.6%) and H. influenzae (18.1%). In contrast, S. aureus (16.9%) and S. pneumoniae (14.9%) were frequently isolated from the patients with chronic bronchitis. Before the drug administration, the bacteria frequently isolated from the patients were S. pneumoniae (20.6%) and H. influenzae (21.5%). The bacteria relatively frequently isolated from the patients treated with cephems or macrolides were P. aeruginosa, and S. aureus was relatively frequently isolated from the patients treated with quinolones.

Aged↗
PubMed2004

Reaction-phase-selective inter- and intramolecular photochemical reaction of 2-pyridone derivatives.

Phase-selective photochemical reaction of 2-pyridone derivatives was examined. Irradiation of 1 in benzene mainly gave rearrangement products 2. However, intermolecular [4 + 4] photocycloaddition proceeded quantitatively in the solid state, affording photodimers 3. An effective pi-pi stacking and dipole-dipole interaction between two pyridone moieties might play important roles in an effective arrangement of 1 for photodimerization in their crystal structures. [reaction: see text]

Journal Article↗
PubMed2004

Partial involvement of group I metabotropic glutamate receptors in the neurotoxicity of 3-N-oxalyl-L-2,3-diaminopropanoic acid (L-beta-ODAP).

Neurolathyrism is a human motoneuron disease caused by the overconsumption of grass pea (Lathyrus sativus) that contains a toxic non-protein amino acid, 3-N-oxalyl-L-2,3-diaminopropanoic acid (L-beta-ODAP). The preventive activities of various glutamatergic agents from acute neuronal death caused by L-beta-ODAP were studied using rat primary cortical neuron/glia culture. Nearly 80% of the rat primary cortical neurons were killed by 300 microM L-beta-ODAP within 24 h. Though antagonists acting on the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor prevented most of the toxicity, antagonists acting on group I metabotropic glutamatergic receptors (mGluRs), including (RS)-1-aminoindan-1,5-dicarboxylic acid (AIDA), (S)-alpha-methyl-4-carboxyphenylglycine (MCPG), and 2-methyl-6-(2-phenylethenyl)pyridine (SIB1893) partially and significantly prevented neuronal death due to L-beta-ODAP. These antagonists, within limited concentrations, did not have any inhibitory effects on the currents through AMPA receptors expressed in Xenopus oocytes. L-beta-ODAP itself did not induce the currents through group I mGluRs expressed in Xenopus oocytes. These results suggest that the neurotoxicity induced by L-beta-ODAP is partially mediated by the activation of group I mGluRs by an indirect mechanisms.

Amino Acids, Diamino↗
PubMed2004

[A case of stage I adenocarcinoma of the lung complicated with inflammatory lesions with an 8-year clinical course before surgery; CT and pathological correlations].

A nodular shadow near left hilum of lung was detected by chest radiography in November 1993 in a 79-year-old woman with hypertension and diabetes. Chest radiography in April 2001 revealed growth of the shadow. Chest CT showed a localized ground-glass opacity in the periphery of the lesion shadow. The resected specimen showed that the nodular shadow was papillary adenocarcinoma and the localized ground-glass opacity indicated the presence of inflammatory lesions. The pathological stage was stage I. Our case was a rare adenocarcinoma complicated with inflammatory changes including a granuloma that appeared 8 years later.

Adenocarcinoma, Papillary↗
PubMed2004

[Susceptibilities of bacteria isolated from patients with lower respiratory infectious diseases to antibiotics (2002)].

From October 2002 to September 2003, we collected the specimen from 476 patients with lower respiratory tract infections in 16 institutions in Japan, and investigated the susceptibilities of isolated bacteria to various antibacterial agents and patients' characteristics. Of 584 strains that were isolated from specimen (mainly from sputum) and assumed to be bacteria causing in inflammation, 578 strains were examined. The breakdown of the isolated bacteria were: Staphylococcus aureus 77, Streptococcus pneumoniae 103, Haemophilus influenzae 95, Pseudomonas aeruginosa (non-mucoid) 61, P. aeruginosa (mucoid) 23, Klebsiella pneumoniae 36, Moraxella subgenus Branhamella catarrhalis 29, etc. Of 77 S. aureus strains, those with 2 microg/ml or less of MIC of oxacillin (MPIPC) [methicillin-susceptible S. aureus: MSSA] was 34 strains (44.2%) and those with 4 microg/ml or more of MIC of oxacillin (methicillin-resistant S. aureus: MRSA) was 43 strains (55.8%). Against MSSA, imipenem (IPM) and minocycline (MINO) had the most potent antibacterial activity and inhibited the growth of all the strains at 0.25 microg/ml. Although clindamycin (CLDM) and aminoglycosides also had the potent activity, the resistant strains against those agents were detected. Cefotiam (CTM) inhibited the growth of all the strains at 1 microg/ml without the low sensitive strains. Against MRSA, vancomycin (VCM) showed the most potent activity and inhibited the growth of all the strains at 2 microg/ml. Arbekacin (ABK) also showed the relatively potent activity and inhibited the growth of all the strains at 4 microg/ml. Carbapenems showed the most potent activities against S. pneumoniae and inhibited the growth of all the strains at 0.25-0.5 microg/ml. Cefozopran (CZOP) also had a preferable activity (MIC90: 1 microg/ml) and inhibited the growth of all the strains at 2 microg/ml. In contrast, the resistant strains for cefaclor (CCL), erythromycin (EM), CLDM, and tetracycline (TC) were detected in 50.5%, 76.7%, 50.5%, and 80.6% of all the strains, respectively. Against H. influenzae, LVFX showed the most potent activity and inhibited the growth of 92 of all the strains (96.8%) at 0.063 microg/ml. Tobramycin (TOB) showed the most potent activity against P. aeruginosa (both mucoid and non-mucoid) and inhibited the growth of all the strains at 2 microg/ml. The antibacterial activity of CZOP was good and its MIC90 against mucoid and non-mucoid strains was 8 and 16 microg/ml, respectively. CZOP and cefpirome (CPR) were the most potent against K. pneumoniae with 0.125 microg/ml of MIC90. Also, all the agents generally showed potent activities against M. (B.) catarrhalis and the MIC90 of all drugs were 4 microg/ml or less. The approximately half the number (47.5%) of the patients with respiratory infection were aged 70 years or older. As for the incidence by the diseases, bacterial pneumonia and chronic bronchitis were the highest, being noted in 35.7 and 33.8% of all the patients, respectively. The bacteria frequently isolated from the patients with bacterial pneumonia were S. pneumoniae (22.6%). In contrast, S. aureus (16.6%) and P. aeruginosa (13.7%) were relatively frequently isolated from the patients with chronic bronchitis. Before the drug administration, the bacteria frequently isolated from all the patients were H. influenzae (24.5%) and S. pneumoniae (24.2%). In comparison of the isolated bacteria by pretreatment agents, P. aeruginosa was relatively frequently isolated from the patients pretreated with cephems or macrolides and H. influenzae was relatively frequently isolated from the patients pretreated with penicillins.

Anti-Bacterial Agents↗
PubMed2004

[A case of liver metastasis of gastric cancer responding well to TS-1].

We report the case of a 79-year-old female with gastric cancer accompanied by liver metastasis that was successfully treated by TS-1, a novel oral fluoropyrimidine derivative. Abdominal CT scan showed a low-density area in the lateral segment of the liver and lymph node swelling in the right side of the abdominal aorta. One treatment course consisted of 4 weeks of TS-1 administration (100 mg daily) followed by a 2-week break. After 2 courses of this treatment, an abdominal CT scan showed no evidence of liver metastasis and a reduction of lymph nodes metastasis. The serum level of CA19-9 was reduced from 780 U/ml to within a normal range. Grade 1-2 toxicity (nausea and diarrhea) was seen after 2 courses. We conclude that TS-1 may be beneficial in the treatment of the liver metastasis of gastric cancer.

Administration, Oral↗
PubMed2004

[Three successful case reports of advanced gastric cancer with chemotherapy].

We report three successful cases with continuous systemic chemotherapy for advanced gastric cancer. Case 1: A 67-year-old male with gastric cancer. Abdominal CT showed the invasion in the pancreas and as a result, continuous systemic infusion of low-dose cisplatin (CDDP 20 mg/day) and 5-fluorouracil (5-FU 1,000 mg/day) was performed. This infusion chemotherapy, CDDP and 5-FU, was continued for 5 days and discontinued for 25 days. Three months after the chemotherapy, the main tumor was remarkably reduced (downstaging was obtained), and consequently, total gastrectomy was performed. Case 2: A 78-year-old male with gastric cancer and hepatic multiple metastases. Abdominal CT scan before operation did not reveal the hepatic metastasis. In the operation for distal gastrectomy, we found multiple metastases on the surface of the liver. Continuous systemic infusion of low-dose CDDP (20 mg/day) and 5-FU (1,000 mg/day) was performed. This infusion chemotherapy, CDDP and 5-FU, was continued for 5 days and discontinued for 2 days. One month after the chemotherapy, Liver metastases had almost disappeared. Case 3: A 73-year-old male had received a distal gastrectomy based on the diagnosis of gastric cancer. The tumor marker, CA19-9, immediately decreased after the operation, but had increased again. He was treated with a combination chemotherapy of TS-1 and CDDP. The treatment consisted of 4 weeks of TS-1 administration (100 mg daily) followed by a 2-week break. CDDP of 10 mg/day was infused intravenously (day 1-5). Four weeks after the infusion, CA19-9 had returned to almost normal. We conclude that the combination chemotherapy of 5-FU (or TS-1) and CDDP might be an effective treatment for advanced and metastatic gastric cancer.

Aged↗
PubMed2003

Genomics approach to abscisic acid- and gibberellin-responsive genes in rice.

We used an 8987-EST collection to construct a cDNA microarray system with various genomics information (full-length cDNA, expression profile, high accuracy genome sequence, phenotype, genetic map, and physical map) in rice. This array was used as a probe to hybridize target RNAs prepared from normally grown callus of rice and from callus treated for 6 hr or 3 days with the hormones abscisic acid (ABA) or gibberellin (GA). We identified 509 clones, including many clones that had never been annotated as ABA-or GA-responsive. These genes included not only ABA- or GA-responsive genes but also genes responsive to other physiological conditions such as pathogen infection, heat shock, and metal ion stress. Comparison of ABA- and GA-responsive genes revealed antagonistic regulation for these genes by both hormones except for one defense-related gene, thionin. The gene for thionin was up-regulated by both hormone treatments for 3 days. The upstream regions of all the genes that were regulated by both hormones had cis-elements for ABA and GA response. We performed a clustering analysis of genes regulated by both hormones and various expression profiles that showed three notable clusters (seed tissues, low temperature and sugar starvation, and thionin-gene related). A comparison of the cis-elements for hormone response genes between rice and Arabidopsis thaliana, we identified cis-elements for dehydration-stress response or for expression of amylase gene as Arabidopsis gene-specific or rice gene-specific, respectively.

Abscisic Acid↗
PubMed2003

Antisense transcripts with rice full-length cDNAs.

BACKGROUND: Natural antisense transcripts control gene expression through post-transcriptional gene silencing by annealing to the complementary sequence of the sense transcript. Because many genome and mRNA sequences have become available recently, genome-wide searches for sense-antisense transcripts have been reported, but few plant sense-antisense transcript pairs have been studied. The Rice Full-Length cDNA Sequencing Project has enabled computational searching of a large number of plant sense-antisense transcript pairs. RESULTS: We identified sense-antisense transcript pairs from 32,127 full-length rice cDNA sequences produced by this project and public rice mRNA sequences by aligning the cDNA sequences with rice genome sequences. We discovered 687 bidirectional transcript pairs in rice, including sense-antisense transcript pairs. Both sense and antisense strands of 342 pairs (50%) showed homology to at least one expressed sequence tag other than that of the pair. Microarray analysis showed 82 pairs (32%) out of 258 pairs on the microarray were more highly expressed than the median expression intensity of 21,938 rice transcriptional units. Both sense and antisense strands of 594 pairs (86%) had coding potential. CONCLUSIONS: The large number of plant sense-antisense transcript pairs suggests that gene regulation by antisense transcripts occurs in plants and not only in animals. On the basis of our results, experiments should be carried out to analyze the function of plant antisense transcripts.

DNA, Antisense↗