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111.
Molecular phylogenetics of Stenodermatini bat genera: congruence of data from nuclear and mitochondrial DNA 总被引:2,自引:1,他引:1
Van den Bussche RA; Baker RJ; Wichman HA; Hamilton MJ 《Molecular biology and evolution》1993,10(5):944-959
Within the tribe Stenodermatini the systematics of the complex of species
allied with the genus Artibeus has generated several alternative
phylogenetic hypotheses. The most recent treatment recognized four genera
(Artibeus, Dermanura, Enchisthenes, and Koopmania) and suggested that the
most recent common ancestor of these four genera would include the common
ancestor of all other currently recognized Stenodermatini genera except
Sturnira. To test this hypothesis, we examined an EcoRI-defined nuclear
satellite DNA repeat and 402 bp of DNA sequence variation from the
mitochondrial cytochrome b gene. Phylogenetic conclusions based on Southern
blot analyses, in situ hybridization, and mitochondrial DNA sequence data
indicate that Enchisthenes is not closely related to Dermanura, Artibeus,
or Koopmania and that Dermanura, Artibeus, and Koopmania shared a common
ancestor after diverging from the remainder of the Stenodermatini. If our
conclusions are correct, then justification for recognizing Dermanura and
Koopmania as generically distinct from Artibeus must be based on the
magnitude of difference that distinguishes each rather than on the
conclusion that to place them as congeneric with Artibeus creates a
paraphyletic taxon.
相似文献
112.
G Nivaler EA Zimmerman R Defendini AS Liotta DT Kreiger MJ Brownstein 《The Journal of cell biology》1979,81(1):50-58
Adrenocorticotropin and β-lipotropin (β-LPH) have been localized by immunoperoxidase methods in nerve cells and fibers of the hypothalamus and brain stem of the ewe. 6-μm sections were immunostained first for either ACTH or β-LPH. The reaction products and the antibody complexes were then eluted completely from the tissue, and the same section was immunostained for the second peptide. Absorption of the primary antisera with a variety of peptide fragments of ACTH and β-LPH demonstrated, immunocytochemically as well as by radioimmunoassay, that the ACTH and β-LPH antisera were directed to the COOH- and NH(2)-termini of the peptides, respectively. Neither antiserum recognized any portion of the heterologous peptide. In the sequential staining procedure on the same tissue section, preincubation of the antisera with the homologous peptide abolished the staining, whereas preincubation with the heterologous peptide did not affect it, regardless of the order followed. Every nerve cell in the arcuate nucleus that contained ACTH also contained β-LPH, but β-LPH cells appeared, probably falsely, to be twice as numerous as ACTH cells. β-LPH-positive fibers in and beyond the hypothalamus were also more numerous and stained more intensively than ACTH fibers. The salient exception was fibers in the infundibular zona externa, where the opposite was true. Our observations establish that ACTH and β-LPH are contained in the same nerve cells They stongly favor biosynthesis in brain, probably from a common precursor molecule, as has been demonstrated in the pituitary gland. The complexity of the cytologic distribution pattern described suggests that the two peptides are not processed in the same manner by the nerve cell. 相似文献
113.
114.
Tang WF Yang SY Wu BW Jheng JR Chen YL Shih CH Lin KH Lai HC Tang P Horng JT 《The Journal of biological chemistry》2007,282(8):5888-5898
Enterovirus 71 is an enterovirus of the family Picornaviridae. The 2C protein of poliovirus, a relative of enterovirus 71, is essential for viral replication. The poliovirus 2C protein is associated with host membrane vesicles, which form viral replication complexes where viral RNA synthesis takes place. We have now identified a host-encoded 2C binding protein called reticulon 3, which we found to be associated with the replication complex through direct interaction with the enterovirus 71-encoded 2C protein. We observed that the N terminus of the 2C protein, which has both RNA- and membrane-binding activity, interacted with reticulon 3. This region of interaction was mapped to its reticulon homology domain, whereas that of 2C was encoded by the 25th amino acid, isoleucine. Reticulon 3 could also interact with the 2C proteins encoded by other enteroviruses, such as poliovirus and coxsackievirus A16, implying that it is a common factor for such viral replication. Reduced production of reticulon 3 by RNA interference markedly reduced the synthesis of enterovirus 71-encoded viral proteins and replicative double-stranded RNA, reducing plaque formation and apoptosis. Furthermore, reintroduction of nondegradable reticulon 3 into these knockdown cells rescued enterovirus 71 infectivity, and viral protein and double-stranded RNA synthesis. Thus, reticulon 3 is an important component of enterovirus 71 replication, through its potential role in modulation of the sequential interactions between enterovirus 71 viral RNA and the replication complex. 相似文献
115.
Impacts of yeast metabolic network structure on enzyme evolution 总被引:1,自引:1,他引:0
A comment on D Vitkup, P Kharchenko and A Wagner: Influence of metabolic network structure and function on enzyme evolution. Genome Biol 2006, 7:R39. 相似文献
116.
BD Pascal MJ Chalmers SA Busby CC Mader MR Southern NF Tsinoremas PR Griffin 《BMC bioinformatics》2007,8(1):156
Background
The combination of mass spectrometry and solution phase amide hydrogen/deuterium exchange (H/D exchange) experiments is an effective method for characterizing protein dynamics, and protein-protein or protein-ligand interactions. Despite methodological advancements and improvements in instrumentation and automation, data analysis and display remains a tedious process. The factors that contribute to this bottleneck are the large number of data points produced in a typical experiment, each requiring manual curation and validation, and then calculation of the level of backbone amide exchange. Tools have become available that address some of these issues, but lack sufficient integration, functionality, and accessibility required to address the needs of the H/D exchange community. To date there is no software for the analysis of H/D exchange data that comprehensively addresses these issues. 相似文献117.
López-Calderón MJ U Figueroa-Viramontes M Fortis-Hernández G Núñez-Hernández E Ochoa-Martínez JI Sanchez-Duarte 《Phyton》2015,84(1):8-13
An experiment with increasing rates of fertilizer and manure in silage corn was established to evaluate the agronomic crop response and to estimate the manure nitrogen availability. The treatments were designed to deliver 0, 67, 100 and 133% of the crop nitrogen requirements (CNR), using ammonium sulphate and manure as N source. Dry matter (DM) yield was similar among treatments receiving N, but those values were greater than those found in the control. Nitrogen extraction at harvest was not statistically different in treatments with fertilizer or manure, but it was higher in these treatments than in the control without N (p≤ 0.05). With both sources of N, crop N extraction was adjusted to a quadratic regression equation, as a function of N rates. According to the fertilizer equivalence (EF) methodology, the rate of 231.3 kg/ha of inorganic fertilizer N, and 752.9 kg/ha of total N in manure, had 129.5 kg/ha of N extracted by the crop. The ratio of the above rates, fertilizer N/ manure total N, represents the crop available manure N; in the present study, it was 30.7% of total N in the manure. Since no differences in yield were observed between N sources, it is concluded that N fertilizer can be substituted by manure, at a rate estimated to provide the crop N requirements. The estimation of the manure available N is important to adjust manure rates, thereafter avoiding excessive applications and pollution risks. 相似文献
118.
119.
目的: 由于传统呼吸调控环路忽略了对血液循环的决定性作用,肺(静脉)血管容量相关研究甚少,亟需建立肺血管容量测量方法。方法: 选择正常志愿者完成CT全肺扫描,图像数据经过计算机软件分析处理,从肺尖到肺底以40~50层进行肺野手工切划,相邻层间由计算机自动模拟连接,在去除干扰后进行全肺血管(≥0.6 mm)高精度三维立体成像技术处理,进而计算全肺和肺血管容积。结果: 12例正常志愿者从肺尖到肺底CT扫描图片层数为530±98(431~841)张。全肺和肺血管的总容积是3705±857(2398~5383)ml ,肺血管血液总的容积是125±32(94~201)ml。按肺静脉系统血管容量约为全肺血管血液容量一半计算,应该是63±16(47~100)ml。结论: 肺CT扫描数据分析三维立体成像建立肺血管容量无创测量方法精确可行。 相似文献
120.
A. Laperche Y. Aigu M. Jubault M. Ollier S. Guichard P. Glory SE. Strelkov A. Gravot MJ. Manzanares-Dauleux 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2017,130(4):669-684