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排序方式: 共有4516条查询结果,搜索用时 15 毫秒
1.
Young-Ok Kim Sooyeon Park Hyangmi Kim Doo-Sang Park Bo-Hye Nam Dong-Gyun Kim Jung-Hoon Yoon 《Antonie van Leeuwenhoek》2014,105(5):881-889
A Gram-negative, non-motile and rod-shaped bacterial strain, designated RA2-3T, was isolated from a sea squirt (Halocynthia roretzi) collected from the South Sea, Korea, and its taxonomic position was investigated by using a polyphasic approach. Strain RA2-3T was observed to grow optimally at 25 °C, at pH 7.0–7.5 and in the presence of 2 % (w/v) NaCl. Strain RA2-3T exhibited the highest 16S rRNA gene sequence similarity values to the type strains of Litoreibacter meonggei (95.7 %), Planktotalea frisia (95.6 %), Thalassobius gelatinovorus (95.5 %) and Pelagicola litoralis (95.4 %). A neighbour-joining phylogenetic tree based on 16S rRNA gene sequences revealed that strain RA2-3T clustered with the type strains of Planktotalea frisia, Pelagicola litoralis, Pacificibacter maritimus and Roseovarius marinus. Strain RA2-3T was found to contain Q-10 as the predominant ubiquinone and C18:1 ω7c as the major fatty acid. The major polar lipids detected in strain RA2-3T were phosphatidylcholine, phosphatidylglycerol, one unidentified aminolipid and one unidentified lipid. The DNA G+C content of strain RA2-3T was 52.9 mol%. On the basis of the phylogenetic, chemotaxonomic and phenotypic properties, strain RA2-3T is considered to represent a new genus and species within the family Rhodobacteraceae, for which the name Halocynthiibacter namhaensis gen. nov., sp. nov. is proposed. The type strain of H. namhaensis is RA2-3T (=KCTC 32362T=NBRC 109999T). 相似文献
2.
The same mammalian replicon yields distinct recombination products in different cell lines. 总被引:4,自引:0,他引:4
H K Vu L Delbecchi D Bourgaux-Ramoisy P Bourgaux 《The Journal of biological chemistry》1991,266(14):9320-9326
We have observed previously that some chimeric replicons inclusive of a partly duplicated polyomavirus (Py) genome yield unit-length Py DNA (P155) at high frequency when transfected into normal or Py-transformed mouse cells. We demonstrate here that one such replicon generates either P155 or illegitimate recombination products in other mouse cells, transformed by simian virus 40. Use of the polymerase chain reaction indicates that each of the illegitimate products carried a different deletion, but that all deletions mapped within a rather well defined portion of the precursor replicon. Thus, these products were organized as if two hotspots for recombination existed in the Py late-coding region, one being located within or near one of the duplicated sequences characteristic of the chimeric replicon. Since this particular hotspot has already been shown to be involved in the generation of P155, the data reported here could indicate that a single recombination mechanism can yield either homologous (P155) or illegitimate products. How the DNA interacts with certain proteins, such as papovavirus large tumor antigen, could explain why one or the other type of product is formed. 相似文献
3.
4.
Cao Dinh Hung Chang-Hee Hong Seon-Ki Kim Kyu-Han Lee Jea-Young Park Min-Woo Nam Dae-Ho Choi Hye-In Lee 《Acta Physiologiae Plantarum》2016,38(6):152
Light-emitting diodes (LEDs) are useful for the growth of many plants, but not known for blueberry species. This study examined the effects of fluorescent lamps and 100 % red, 80 % red plus 20 % blue, 50 % red plus 50 % blue, and 100 % blue LEDs on the growth and development of highbush blueberry shoots under aseptic and non-aseptic conditions. Results revealed that monochromatic blue LEDs accumulated the highest contents of leaf chlorophylls. In contrast, monochromatic red LEDs inhibited chlorophyll accumulation, but produced the longest shoots and roots and provided high percentages of side shoot formation from ex vitro plants. Mixed LEDs, particularly 50 % red plus 50 % blue light, improved plant growth with respect to notably increased shoot and root biomass. Direct rooting of in vitro shoots under non-aseptic conditions was readily achieved using a commercial mixture of perlite and peat moss with high humidity controls. These findings obviously suggest the efficient use of LEDs to replace traditional fluorescent lamps in large-scale propagation of the highbush blueberry, and also pave the way for future studies on LEDs for standardizing micropropagation protocols to shrub crops and woody plants. 相似文献
5.
Follicles are important in oocyte maturation. Successful estrous cycle requires remodeling of follicular cells, and proper execution of programmed cell death is crucial for normal follicular development. The objectives of the present study were to understand programmed cell death during follicle development, to analyze the differential follicle development patterns, and to assess the patterns of apoptosis and autophagy expression during follicle development in normal and miniature pigs. Through the analysis of differential patterns of programmed cell death during follicular development in porcine, MAP1LC3A, B and other autophagy-associated genes (ATG5, mTOR, Beclin-1) were found to increase in normal pigs, while it decreased in miniature pigs. However, for the apoptosis-associated genes, progression of genes during follicular development increased in miniature pigs, while it decreased in normal pigs. Thus, results show that normal and miniature pigs showed distinct patterns of follicular remodeling manifesting that programmed cell death largely depends on the types of pathway during follicular development (Type II or autophagy for normal pigs and Type I or apoptosis for miniature pigs). 相似文献
6.
The desulfurization activity of the resting cells of Gordona sp. CYKS1 was strongly depended on harvest time and the highest value when the cells had been harvested in the early growth phase (0.12 mg sulfur g–1 cell–1 h–1). For the model oil, hexadecane containing dibenzothiophene, the specific desulfurization rate decreased as the reaction proceeded. Both the specific and the volumetric desulfurization rates were not significantly affected by the aqueous-to-oil phase ratio. The diesel oils, light gas oil and a middle distillate unit feed were desulfurized at higher rates (ca. 0.34 mg sulfur g–1 cell–1 h–1) than the model oil (0.12 mg sulfur g–1 cell–1 h–1). 相似文献
7.
8.
Giang Ngan Khong Nhu Thi Le Mai Thi Pham Helene Adam Carole Gauron Hoa Quang Le Dung Tien Pham Kelly Colonges Xuan Hoi Pham Vinh Nang Do Michel Lebrun Stefan Jouannic 《PLoS genetics》2021,17(6)
The number of grains per panicle is an important yield-related trait in cereals which depends in part on panicle branching complexity. One component of this complexity is the number of secondary branches per panicle. Previously, a GWAS site associated with secondary branch and spikelet numbers per panicle in rice was identified. Here we combined gene capture, bi-parental genetic population analysis, expression profiling and transgenic approaches in order to investigate the functional significance of a cluster of 6 ANK and ANK-TPR genes within the QTL. Four of the ANK and ANK-TPR genes present a differential expression associated with panicle secondary branch number in contrasted accessions. These differential expression patterns correlate in the different alleles of these genes with specific deletions of potential cis-regulatory sequences in their promoters. Two of these genes were confirmed through functional analysis as playing a role in the control of panicle architecture. Our findings indicate that secondary branching diversity in the rice panicle is governed in part by differentially expressed genes within this cluster encoding ANK and ANK-TPR domain proteins that may act as positive or negative regulators of panicle meristem’s identity transition from indeterminate to determinate state. 相似文献
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10.
T H Vu F M Tacchini-Cottier C E Day A B Begovich P P Jones 《Journal of immunology (Baltimore, Md. : 1950)》1988,141(10):3654-3661
Four of the eleven independent H-2 haplotypes of inbred mouse strains and approximately 15% of wild mouse chromosomes 17 fail to express the E alpha E beta class II histocompatibility (Ia) Ag. These E- haplotypes are defective in the expression of the E alpha and/or the E beta chain. None of the E beta defects has previously been described at the molecular level. In this study, we report the molecular basis for the defective expression of the E beta gene from the w17 haplotype of the H-2 congenic strain B10.CAS2, derived from wild Mus musculus castaneus. Comparison of the Ew17 beta genomic sequence to those of the functional Eb beta and Ed beta genes reveals a single base insertion in the RNA donor splice site of the first intron. By DNA shuffling, we have corrected the single base mutation, and we show by FACS analysis and 2-D PAGE of immunoprecipitates that the corrected Ew17 beta is expressed in L cells when co-transfected with an Ed alpha gene. Conversely, an Eb beta gene construct containing the mutant RNA splice site from Ew17 beta is not expressed. We conclude that the single base insertion in the first RNA splice donor site is the sole molecular defect in the Ew17 beta gene. 相似文献