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21.
Mutations in RAB27A cause Griscelli syndrome associated with haemophagocytic syndrome 总被引:19,自引:0,他引:19
Ménasché G Pastural E Feldmann J Certain S Ersoy F Dupuis S Wulffraat N Bianchi D Fischer A Le Deist F de Saint Basile G 《Nature genetics》2000,25(2):173-176
Griscelli syndrome (GS, MIM 214450), a rare, autosomal recessive disorder, results in pigmentary dilution of the skin and the hair, the presence of large clumps of pigment in hair shafts and an accumulation of melanosomes in melanocytes. Most patients also develop an uncontrolled T-lymphocyte and macrophage activation syndrome (known as haemophagocytic syndrome, HS), leading to death in the absence of bone-marrow transplantation. In contrast, early in life some GS patients show a severe neurological impairment without apparent immune abnormalities. We previously mapped the GS locus to chromosome 15q21 and found a mutation in a gene (MYO5A) encoding a molecular motor in two patients. Further linkage analysis suggested a second gene associated with GS was in the same chromosomal region. Homozygosity mapping in additional families narrowed the candidate region to a 3.1-cM interval between D15S1003 and D15S962. We detected mutations in RAB27A, which lies within this interval, in 16 patients with GS. Unlike MYO5A, the GTP-binding protein RAB27A appears to be involved in the control of the immune system, as all patients with RAB27A mutations, but none with the MYO5A mutation, developed HS. In addition, RAB27A-deficient T cells exhibited reduced cytotoxicity and cytolytic granule exocytosis, whereas MYO5A-defective T cells did not. RAB27A appears to be a key effector of cytotoxic granule exocytosis, a pathway essential for immune homeostasis. 相似文献
22.
Roest Crollius H Jaillon O Bernot A Dasilva C Bouneau L Fischer C Fizames C Wincker P Brottier P Quétier F Saurin W Weissenbach J 《Nature genetics》2000,25(2):235-238
The number of genes in the human genome is unknown, with estimates ranging from 50,000 to 90,000 (refs 1, 2), and to more than 140,000 according to unpublished sources. We have developed 'Exofish', a procedure based on homology searches, to identify human genes quickly and reliably. This method relies on the sequence of another vertebrate, the pufferfish Tetraodon nigroviridis, to detect conserved sequences with a very low background. Similar to Fugu rubripes, a marine pufferfish proposed by Brenner et al. as a model for genomic studies, T. nigroviridis is a more practical alternative with a genome also eight times more compact than that of human. Many comparisons have been made between F. rubripes and human DNA that demonstrate the potential of comparative genomics using the pufferfish genome. Application of Exofish to the December version of the working draft sequence of the human genome and to Unigene showed that the human genome contains 28,000-34,000 genes, and that Unigene contains less than 40% of the protein-coding fraction of the human genome. 相似文献
23.
Hans Fischer 《Cellular and molecular life sciences : CMLS》1946,2(8):323-324
Ohne Zusammenfassung 相似文献
24.
Kurt H. Meyer Ed. H. Fischer P. Bernfeld 《Cellular and molecular life sciences : CMLS》1946,2(9):362-363
Summary The -amylase of hog pancreas has been purified and the degree of purity controled by electrophoresis. The active substance is a protein which can dissociate in an unstable high molecular component and a thermostable component of low molecular weight. 相似文献
25.
26.
Sex allocation in animals 总被引:1,自引:0,他引:1
27.
H. -D. Jakubke H. Däumer A. Könnecke P. Kuhl J. Fischer 《Cellular and molecular life sciences : CMLS》1980,36(9):1039-1040
Summary The affinity of N-acyl-L-phenylalanine 4-nitroanilides for chymotrypsin is enhanced as the hydrophobicity of non-amino acid residues in the P2-position of the substrates increases, whereas kcat remains nearly constant. On the other hand, if alanine or leucine is in the P2-position kcat increases with decreasing KM. 相似文献
28.
Zusammenfassung Nach einer Injektion von Erythropoietin in hungernde Ratten beobachteten wir eine Erhöhung der Reticulocyten. Junge Formen von Reticulocyten erschienen bereits 12 h nach der Behandlung. Dieser Befund deutet vielleicht darauf hin, dass Erythropoietin nicht nur die Stammzellen angreift.
Supported by Grant No. CY-3071 from the U.S.P.H.S. 相似文献
Supported by Grant No. CY-3071 from the U.S.P.H.S. 相似文献
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