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51.
Nakayama Ishizue; Miyazawa Takeshige; Kobayashi Masatomo; Kamiya Yuji; Abe Hiroshi; Sakurai Akira 《Plant & cell physiology》1990,31(2):195-200
The effects of a novel plant growth regulator (PGR) prohexadionecalcium (BX-112; calcium 3,5-dioxo-4-propionylcyclohexanecarboxylate)on shoot elongation caused by exogenously applied GA1, GA3,GA4) GA19 and GA20 were investigated in rice (Oryza sativa L.cv. Nihonbare and cv. Tan-ginbozu) seedling test. Dependingon the dose, BX-112 reduced shoot elongation in both cultivarscaused by GA19 and GA20, but not by GA1. When a high dose ofBX-112 (e.g. 250 ng/plant and over) was applied with GA1, orGA4, shoot elongation was even promoted. This promotive effect,however, was not observed with GA3. These results suggest thatBX-112 inhibits gibberellin (GA) biosynthesis in the rice plantat the 3ß- and 2ß-hydroxylation of GAs,namely steps of activation and inactivation, respectively. (Received September 6, 1989; Accepted November 27, 1989) 相似文献
52.
53.
Sa-nga Pattanakitsakul Kohzo Nakayama Morinobu Takahashi Masaru Nonaka 《Immunogenetics》1990,32(6):431-439
Mice bearing the H-2
w7
haplotype have five C4-related genes and constitutively express the Slp antigen. To understand the structure and evolution of the five C4-related genes of the C3H.W7 mouse, we have determined nucleotide sequences of the 5 end region of these genes. A C4/Slp hybrid nature was confirmed for three of five C4-related genes as predicted previously by restriction enzyme analysis. The nucleotide sequences of the 5 flanking regions of these three hybrid genes showed close similarity to that of the C4 gene, while the 3 side of the ninth exon of the three hybrid genes showed close similarity to that of the Slp gene. In contrast, the regions between the first exon and the middle of the ninth exon of the three hybrid genes showed a mosaic structure of C4-like and Slp-like sequences. Moreover, the boundaries of the C4-like and Slp-like sequences were quite different among the three hybrid genes. The pattern of nucleotide sequence diversity in this region among the five C4-related sequences could be mainly explained not by point mutations but by gene conversions or unequal crossovers. These results suggest that multiple genetic recombinational events between two homologous sequences played an important role in the generation and diversification of the extra copies of the C4/Slp gene in the H-2
w7
mouse.The nucleotide sequence data reported in this paper have been submitted to the DDBJ, EMBL, and GenBank nucleotide sequence databases and have been assigned the accession numbers D90167-71. 相似文献
54.
H Nakayama Y Hatanaka E Yoshida K Oka M Takanohashi Y Amano Y Kanaoka 《Biochemical and biophysical research communications》1992,184(2):900-907
Forty three percent of the labeled sites, at least, in the electroplax sodium channel with a photoactivable tetrodotoxin derivative were identified by probing protease-digested labeled fragments with several sequence-directed antibodies. They are located in the loop between segments S5 and S6 of domain IV, as well as the region containing transmembrane segment S6 and adjacent extracellular and cytoplasmic sequences in domain III. No photolabeled fragments were detected in the corresponding region of domain I. These results suggest that C-11 of tetrodotoxin where the photoreactive moiety is attached orients to the region between S5 and S6 in domain III and IV. Probable orientation of the tetrodotoxin molecule in sodium channels is considered by taking together with the recent report of the site-directed mutagenesis. 相似文献
55.
Nucleotide sequence of the sex pheromone inhibitor (iAD1) determinant of Enterococcus faecalis conjugative plasmid pAD1 总被引:17,自引:0,他引:17
The determinant for the peptide sex pheromone inhibitor iAD1 (iad) on the hemolysin/bacteriocin plasmid pAD1 of Enterococcus faecalis was sequenced. The sequence reveals a 22-amino-acid precursor with the carboxyl-terminal 8 residues corresponding to iAD1. It appears that iAD1 is a component of its own signal sequence. 相似文献
56.
Y. Hirose K. Ohmuro M. Saigoh T. Nakayama Y. Yamagata 《Origins of life and evolution of the biosphere》1990,20(6):471-481
A model primitive gas containing a mixture of N2, CO and water vapor over a water pool (300 mL, 37 °C) was subjected to electric discharges. The discharge vessel (7 L in volume) was equipped with a CO2 absorber (The CO2 being formed during the discharge), thus simulating possible absorption of CO2 in the primitive ocean. The vessel also has a cold trap ( –15 °C), which protects the primary products against the further decomposition in the discharge phase by enabling these products to adhere to the trap. Since the partial pressures of CO and N2 decreased at rates of 1.5–1.7 cmHg day–1 and 0.1–0.2 cmHg day–1, respectively, the gases were added at regular intervals. The solution was analyzed at regular intervals for HCN, HCHO and urea, and maximum concentrations of about 50, 2, and 140 mM were observed. The discharge phase was continued for 6 months. In the solution, glycine (5.6% yield based on the carbon), glycylglycine (0.64%), orotic acid (0.004%) and small amounts of the other amino acids were found. 相似文献
57.
Aino virus (AIV; JaNAr 28 strain) 103 TCID50/0.2 ml was inoculated in the yolk sac of 8-day-old chick embryos. Recovery and titration of the virus from various organs including the central nervous system (CNS) and skeletal muscle were performed at 2, 4, 7, 10 and 13 days after inoculation (PI). AIV was systemically disseminated and proliferated even 2 days PI. The titers of the recovered virus from the CNS and from skeletal muscle was the highest at 4 days PI and declined with time, whereas hydranencephaly, arthrogryposis and cerebellar hypoplasia developed at 7 days PI and gradually progressed until 13 days PI. 相似文献
58.
Shinichiro Nakamura Wijit Kiatipattanasakul Hiroyuki Nakayama Fumiko Ono Ippei Sakakibara Yasuhiro Yoshikawa Naoaki Goto Kunio Doi 《Journal of medical primatology》1996,25(4):294-300
Abstract: In this study, we immunohistochemically examined the several constituents of senile plaques (SPs) and cerebral amyloid angiopathy (CAA) in aged cynomolgus monkeys. Apolipoprotein E (apoE) deposited in all mature plaques and CAA, and in half of the diffuse plaques. Alpha-1-antichymotripsin (αACT) deposited in half of the mature plaques and in one third of the CAA. Amyloid precursor protein (APP), ubiquitin (Ub), and microtubule-associated protein-2 (MAP-2) accumulated in the swollen neurites of mature plaques. Glial fibrillary acidic protein (GFAP) was detected in the astrocytes and their processes surrounding the mature plaques. Tau was detected in neither the SPs nor CAA. Therefore, mature plaques involved extracellular Aβ, apoE, and αACT, and also astrocytes and swollen neurites. However, diffuse plaques involved only extracellular Aβ and apoE. Since these features, except for tau, were consistent with those in humans, this animal model will be useful for studying the pathogenesis of cerebral amyloid deposition. 相似文献
59.
Takeshi K. Watanabe Toyomasa Katagiri Mikio Suzuki Fumio Shimizu Tsutomu Fujiwara Naohide Kanemoto Yusuke Nakamura Yoshikatsu Hirai Hiroumi Maekawa Ei-ichi Takahashi 《Genomics》1996,38(3):273
From a human fetal-brain cDNA library we isolated two novel genes encoding peptides containing six EGF-like repeats. Both showed significant homologies with nel, a gene strongly expressed in neural tissues of chicken. The cDNAs, designated NELL1 (nel-like, type 1) and NELL2 (nel-like, type 2), contained open reading frames encoding 810 and 816 amino acids, respectively. NELL2 is strongly expressed in brain of adult and fetus but only weakly in fetal kidney. NELL1 and NELL2 were mapped by FISH to chromosomal bands 11p15.1–p15.2 and 12q13.11–q13.12, respectively. 相似文献