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N. J. Lassam Zheng Lin Michael G. Shennan Anouk Courseaux Bin T. Teh Patrick Gaudray Catharina Larsson 《Human genetics》1997,99(6):776-780
MLK-3 kinase is a widely expressed serine/ threonine kinase that bears multiple protein interaction domains and regulates
signals mediated by the stress-responsive pathway. Thus, MLK-3 signaling affects numerous cellular processes, raising the
possibility that MLK-3 might play a role in oncogenesis. In this report, we describe the fine mapping of the MLK-3 gene within the 11q13.1 chromosomal region. By integrating data from somatic cell hybrids and double color fluorescence in
situ hybridization on metaphase chromosomes and DNA fibers, MLK-3 has been assigned approximately 1 Mb telomeric of PYGM, close to the D11S546 locus. Since the MEN1 susceptibility locus is also located within the 11q13.1 region, we have carried
out Southern and Northern blot analyses, as well as protein truncation assays to establish whether abnormalities in MLK-3 lead to the development of this familial cancer syndrome. Our observations exclude MLK-3 as the MEN1 gene.
Received: 25 September 1996 / Revised: 16 December 1996 相似文献
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Rat liver deflavoxanthine dehydrogenase has been prepared by incubating native enzyme with calcium chloride. On reconstitution with FAD, about 85% of the original activity is recovered, all which is the O2-dependent type. In contrast, when dithiothreitol-treated deflavoenzyme is incubated with FAD, the recovery of activity is almost the same as above, but most of the recovered activity is of the NAD-dependent type. Deflavoenzyme with or without previous treatment with dithiothreitol was also reconstituted with two artificial FAD analogues, 8-mercapto-FAD and 6-OH-FAD. The difference spectra between the reconstituted enzymes and the initial deflavoenzyme indicate that, in each case, the FAD analogue is bound in its neutral form in dithiothreitol-treated enzyme, whereas it is bound in the anionic form in enzyme without previous dithiothreitol treatment. Furthermore, the protonated forms can be converted into the anionic forms on storage with a concomitant change of activity from the NAD-dependent to the O2-dependent type. This clearly indicates different environments around FAD in the two types of enzyme protein, which are shown to be interconvertible through oxidation-reduction of enzyme cysteinyl residues. 相似文献
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Despite increasing interest in the behavior of zoo animals, studies of nocturnal behavior of zoo animals are limited. In this study, we investigated the relationship between parturition, season, and the sleep‐related behaviors in captive reticulated giraffes to better understand the nocturnal life in giraffes. The subjects were two adult reticulated giraffes living in Kyoto City Zoo, Japan. Observations were made via an infrared camera that was mounted in the indoor enclosure between June 2007 and August 2009. We analyzed video clips that were recorded between 16:30 and 09:00 the next morning, over a total of 199 days. Sleep‐related behaviors were classified into two categories based on the posture of the giraffes; recumbent posture and paradoxical sleep. We also recorded the laterality of recumbent posture, which was coded based on the direction of the legs against the torso (right or left). Seasonal differences in sleep behaviors between summer and winter were observed in both individuals. They tended to start to lie down earlier in the winter than in the summer. Parturition also affected the behaviors as both individuals decreased the behaviors before and after the parturition of the female. Additionally, the female lay on her left side less frequently than her right when resuming a recumbent posture in the pre‐parturition period, while such laterality was not observed in the baseline and post‐parturition period. These results suggested that season and parturition are important factors for determining the sleep‐related behaviors in giraffes. Further studies are needed to understand how these changes in sleep affect other welfare parameters. 相似文献
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Aerial images were obtained on 22 July 1999 and 4 August 2000 from five cotton sites infested with Meloidogyne incognita. Images contained three broad bands representing the green (500-600 nm), red (600-700 nm), and near-infrared (700-900 nm) spectrum. Soil samples were collected and assayed for nematodes in the fall at these sites. Sampling locations were identified from images, by locating the coordinates of a wide range of light intensity (measured as a digital number) for each single band, and combinations of bands. There was no single band or band combination in which reflectance consistently predicted M. incognita density. In all 10 site-year combinations, the minimum number of samples necessary to estimate M. incognita density within 25% of the population mean was greater when sampling by reflectance-based classes (3 to 4 per site) than sampling based on the entire site as one unit. Two sites were sampled at multiple times during the growing season. At these sites, there was no single time during the growing season optimal to take images for nematode sampling. Aerial infrared photography conducted during the growing season could not be used to accurately determine fall population densities of M. incognita. 相似文献
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