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排序方式: 共有6348条查询结果,搜索用时 15 毫秒
1.
Ryan A. Flynn Julia A. Belk Yanyan Qi Yuki Yasumoto Jin Wei Mia Madel Alfajaro Quanming Shi Maxwell R. Mumbach Aditi Limaye Peter C. DeWeirdt Cameron O. Schmitz Kevin R. Parker Elizabeth Woo Howard Y. Chang Tamas L. Horvath Jan E. Carette Carolyn R. Bertozzi Craig B. Wilen Ansuman T. Satpathy 《Cell》2021,184(9):2394-2411.e16
2.
Yuki Shibayama 《Limnology》2012,13(2):199-205
Different disturbance regimes in aquatic habitats may bring about life-history differentiation in aquatic plants. However, there is little information on this association. Adult longevity, seed size and mass, and seed-germination characteristics were surveyed for Nymphoides coreana populations, which grow in different types of aquatic habitats, to demonstrate life-history differentiation. Seed size and seed mass were significantly greater in paddy-field populations (disturbed habitats) than in irrigation-pond populations (stable habitats). Paddy-field populations were composed of annuals, whereas irrigation-pond populations contained perennials. Seed-germination characteristics were significantly different between paddy-field and irrigation-pond populations. The moist-chilling pretreatment period needed to release innate seeds from dormancy was significantly shorter in paddy-field populations than in irrigation-pond populations. The percentage of seeds that germinated was significantly higher under anaerobic conditions, irrespective of light, and under light aerobic conditions compared to dark aerobic conditions in paddy-field populations. Conversely, in irrigation-pond populations, the percentage of seeds that germinated was highest under light anaerobic conditions. These results show that the reaction norm of seed-germination characteristics was significantly broader in annual populations than in perennial populations. The occurrence of aquatic habitats with different disturbance regimes thus contributes to the maintenance of phenotypic diversity in N. coreana populations. 相似文献
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A transposable genetic element was found in the 5'-flanking region of the fibroin H-chain gene in one of the genomic clones from the silkworm Bombyx mori. This element, named K-1.4, is about 1 X 4 X 10(3) base-pairs long, contains an open reading frame of only 225 base-pairs and has inverted repeats of 12 base-pairs at both ends. Duplication of three base-pairs seems to have occurred when this element was integrated into the silkworm genome. About 15 copies of K-1.4 are present per haploid genome of various silkworm strains. Genomic loci of some of these elements are different among different strains or even among individual offspring of the same parents. K-1.4 is present also in the genome of Bombyx mandarina. The K-1.4-related sequences are present in some species belonging to the family Saturniidae. 相似文献
6.
Large scale isolation and some properties of AGY-specific serine tRNA from bovine heart mitochondria 总被引:5,自引:0,他引:5
A method was developed for large scale isolation of AGY-specific serine tRNA (tRNASerAGY) from bovine heart mitochondria. By this method, 5 A260 units of tRNASerAGY were recovered from 6.3 kg of bovine hearts. The nucleotide sequence was identical to that reported previously. tRNASerAGY showed abnormal melting profiles, as was predicted from its unique primary sequence. Its secondary and/or tertiary structure was analyzed by nuclease digestion method. It was suggested that three extra base pairs could occur in the anticodon stem region, with one adenosine residue protruding. The T loop was quite sensitive to nuclease S1, suggesting that the T loop doesn't interact with other regions. This finding is consistent with the model proposed by Sundaralingam (1980). tRNASerAGY was aminoacylated in vitro with only mitochondrial enzyme but not with the enzymes from E. coli and yeast. The aminoacylation rate of tRNASerAGY with mitochondrial enzyme was much faster than that of cytosolic tRNASerUCN, perhaps reflecting differences due to the presence and absence of the D arm of the tRNAs. 相似文献
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Y Wataya H Satake O Hiraoka T Aji K Morishige J Y Kimura A Ishii A Matsuda T Ueda K Fukukawa 《Nucleic acids symposium series》1986,(17):149-151
Carbocyclic inosine is a potent inhibitor for the growth of the promastigote form of Leishmania tropica and Leishmania donovani. In culture, the EC50 values of carbocyclic inosine are 8.3 X 10(-8) and 1.3 X 10(-7) M for the promastigotes of L. tropica and L. donovani, respectively. On the other hand, it is less toxic towards mouse mammary tumor FM3A cells: the EC50 value is 2.7 X 10(-4)M. Carbocyclic inosine is metabolized by Leishmania promastigotes to give carbocyclic adenosine-5'-triphosphate(aristeromycin-5'-triphosphate) and carbocyclic guanosine-5'-triphosphate. This metabolic conversion provides a mechanism for the parasite-selective toxicity of carbocyclic inosine. Carbocyclic inosine was found to be active against L. donovani amastigotes in an in vivo-like cultivation in vitro. 相似文献
9.
Sulfated asparagine-linked sugar chains of hen egg albumin 总被引:8,自引:0,他引:8
The fraction of hen egg albumin glycopeptides mixture, which passes through a Dowex 50-H+ column, contains two sulfate-containing glycopeptides. Based on the structural studies of oligosaccharides released from the glycopeptides by hydrazinolysis, their structures were elucidated as follows. (formula; see text) 相似文献
10.
T Kurihara M Ueda H Okada N Kamasawa N Naito M Osumi A Tanaka 《Journal of biochemistry》1992,111(6):783-787
When an n-alkane-utilizable yeast, Candida tropicalis pK233, was cultivated on butyrate, the fatty acid of shortest chain-length for beta-oxidation, as the sole source of carbon and energy, catalase and the enzymes of the fatty acid beta-oxidation system were inducibly synthesized at high levels. As in the alkane-grown cells, the proliferation of peroxisomes was harmonized with the induction of peroxisomal enzymes. The results of subcellular fractionation and immunoelectronmicroscopy indicated the localization of these enzymes in peroxisomes, not in mitochondria. It was suggested that only peroxisomes have a role in fatty acid beta-oxidation in the yeast cells, unlike in mammalian cells, in which cooperation between peroxisomes and mitochondria is essential. 相似文献