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11.
Van der Woude syndrome (VWS) is the most frequent form of syndromic clefting. Linkage analysis has localized the gene between D1S245 and D1S414, an interval of 4.1 cM with the following order of loci: centromere–D1S245/D1S471–D1S491–D1S205–D1S414–telomere. A microdeletion around D1S205 aided in narrowing the critical region to D1S491–D1S414 by heterozygosity testing. In this study, the location was refined by detection of a recombinant with D1S205 in a new family, indicating that VWS lies between D1S491 and D1S205, a 1.6-cM interval. A roughly 3.5-Mb YAC contig was built from D1S245 through D1S414, encompassing the interval D1S491–D1S205 in level 1 or level 2 paths. Clones were assembled by sequence tagged site (STS) content using the five polymorphic markers from above, four novel STSs identified from YAC ends, and a new STS derived from probe CRI-L461 (D1S70). D1S70 was assigned to the critical region. One single YAC, yCEPH785B2, contains both flanking STSs (D1S491, D1S205). STS content mapping suggests neither chimerism nor deletion of yCEPH785B2 but does suggest that the maximum size of the critical region is approximately 850 kb. All STSs were tested for their presence on a somatic cell hybrid containing the microdeleted chromosome 1 as the sole human chromosome 1 component. Both the proximal and distal ends of the microdeletion mapped to the 850-kb YAC, yCEPH785B2. Therefore, the microdeletion overlapped the critical region, confirming the genetic recombinant data.  相似文献   
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Yeast chromosome III: new gene functions.   总被引:19,自引:1,他引:18       下载免费PDF全文
E V Koonin  P Bork    C Sander 《The EMBO journal》1994,13(3):493-503
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Redaktorial     
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One of a cell biologist's favourite occupations is to discover the proteins that perform newly described functions in the cell. Very often lately, this has resulted in the identification of protein families whose related amino acid sequences reflect similar functions, but can proteins with totally unrelated sequences have similar structures and functions? In this review, Ken Holmes, Chris Sander and Alfonso Valencia describe the structural similarities between three well-known proteins that have no readily detectable primary sequence similarities but for which X-ray crystallography has revealed very similar structures. A comparison of their structures provides insights into their common mechanisms of action and into protein evolution, and has been used to detect related proteins in sequence data bases.  相似文献   
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In order to test for bicoid-like activity in insects other than Drosophila melanogaster, anterior egg cytoplasm from the following species was injected into cleavage stage embryos from mutant D. melanogaster lacking a functional bicoid (bcd) product: six other Drosophila species, the housefly, three blowfly species, the primitive cyclorrhaphic dipteran Megaselia, and the honeybee Apis mellifera; preliminary tests were made with four lower dipterans (Nematocera). Rescue effects were only observed with the drosophilids, housefly, and two of the three blowfly species. Rescue was stronger with the drosophilids than with the other flies as donors. Where checked (D. pseudoobscura), a positive correlation was found between the amount of cytoplasm injected and the number of pattern elements formed, suggesting threshold effects upon target genes as with the endogenous bcd product. By polymerase chain reaction, fragments from a bcd-orthologous homeobox were cloned from the three blowfly species. The derived sequence of 43 amino acids was identical in all blowflies and the housefly but differed at 4 positions from the orthologous D. melanogaster sequence. Localization of the mRNA recognized by the respective fragments in the blowflies Lucilia and Phormia resembled that known from D. melanogaster, while Calliphora — the blowfly species lacking rescue activity —showed remarkable differences of localization in both ovarian follicles and the deposited egg cell. This surprising divergence within a morphologically rather uniform family of cyclorrhaphic dipterans should be of interest from both functional and evolutionary points of view.  相似文献   
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Accurate retention time (RT) prediction is important for spectral library-based analysis in data-independent acquisition mass spectrometry-based proteomics. The deep learning approach has demonstrated superior performance over traditional machine learning methods for this purpose. The transformer architecture is a recent development in deep learning that delivers state-of-the-art performance in many fields such as natural language processing, computer vision, and biology. We assess the performance of the transformer architecture for RT prediction using datasets from five deep learning models Prosit, DeepDIA, AutoRT, DeepPhospho, and AlphaPeptDeep. The experimental results on holdout datasets and independent datasets exhibit state-of-the-art performance of the transformer architecture. The software and evaluation datasets are publicly available for future development in the field.  相似文献   
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Hormonal imprinting takes place at the first encounter of the hormone and receptor, and results in a changed binding capacity and reaction of the cell and its progeny generations. The imprinting effect of three amino acids and their oligopeptides is studied using fluorescent-labelled peptides. Glycine and lysine could provoke positive imprinting (increased binding in the progeny generations) for their own peptides, but alanine could not. Mostly positive imprinting was provoked by glycine and lysine peptides for their own peptides of different chain length. The optimal chain length provoking self-imprinting was four for glycine, two for lysine and three for alanine. Except in this case, alanine was neutral or provoked mostly negative imprinting. After reaching the optimal chain length, there is a decline in binding. Evolutionary conclusions are discussed.  相似文献   
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