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151.
Blood samples were obtained at monthly intervals between April 1994 and March 1996 from captive-bred houbara (Chlamydotis undulata macqueenii), rufous-crested (Eupodotis ruficrista gindiana), and white-bellied (Eupodotis senegalensis) bustards from 4-24 wk of age. Hematology investigations were conducted to determine age-related changes and to establish reference values for growing chicks of these species. There were significant age-related changes in hematocrit, hemoglobin, and red cell count in young birds compared with those of adults. White cell counts (lymphocytes and monocytes) were higher in juvenile birds, compared with adult values. 相似文献
152.
Tovar V del Valle J Zapater N Martin M Romero X Pizcueta P Bosch J Terhorst C Engel P 《Immunogenetics》2002,54(6):394-402
Human CS1, also known as novel Ly9, 19A24, or CRACC, is a member of the immunoglobulin gene superfamily (IgSF) expressed on natural killer cells and other leukocytes. Here we describe the cloning of the mouse homologue of this gene. The mouse novel Ly9 gene is shown to encode a transmembrane protein composed of two extracellular immunoglobulin-like domains, a transmembrane region and an 88-amino acid cytoplasmic domain. Mouse novel Ly9 is structurally similar to the extracellular domains of CD84 and CD229 (Ly9). Both mouse and human novel Ly9 genes mapped close to the CD229gene in a region where other members of the CD150 family have also been mapped, and analysis of their genomic sequences showed that they have an identical intron/exon organization. Northern blot analysis revealed that the expression of mouse and human novel Ly9 was predominantly restricted to hematopoietic tissues, with the exception of testis. Here we show that SAP (SH2D1A), an adapter protein responsible for the X-linked lymphoproliferative disease, binds to the phosphorylated cytoplasmic tail of human but not mouse novel Ly9. Taken together, these data indicate that mouse novel Ly9 is a new member of the expanding CD150 family of cell surface receptors. 相似文献
153.
Specific subcellular targeting and spatial arrangement of signaling molecules are important for efficient signal transduction. The neuro-specific type-I adenylyl cyclase (AC1) is stimulated by Ca2+, and plays an essential role in neurodevelopment and neuroplasticity. We generated hemagglutinin (HA)-tagged AC1 to study its subcellular localization in cultured neurons. The HA-tagged AC1 has similar enzymatic activity and regulatory properties to that of non-tagged protein. HA-AC1 targeted to both apical and basolateral domains in the epithelial Madin-Darby canine kidney (MDCK) cells, and it was found in both axons and dendrites in cultured hippocampal neurons as well as in cerebellar granule neurons. Interestingly, AC1 showed a distinct punctate form of immunostaining in MDCK cells and transfected neurons, suggesting it targets to specific subcellular domains. By immunostaining with different synaptic markers, we found that AC1 puncta were located at the excitatory synapses in cerebellar granule neurons. Our data provide a possible cellular mechanism for the physiological role of AC1 in neuroplasticity. 相似文献
154.
Callistoe vincei nov. gen., nov. sp. is a new South American carnivorous marsupial (Proborhyaenidae, Borhyaenoidea) from Salta Province (Argentina). It is preliminarily described and its phylogenetic relationships with other borhyaenoids are analyzed. The holotype is a complete skull with almost complete postcranial skeleton (missing the pelvis and the tail). It is from the Lumbrera Formation (Early Eocene of northwestern Argentina). It represents the most complete proborhyaenid specimen ever discovered and one of the best-preserved borhyaenoid. In the present paper we analyze the major cranial and dental features, the essential elements to compare C. vincei to Arminiheringia auceta, a Casamayoran proborhyaenid of Patagonia. C. vincei is smaller, much more gracile; its skull is narrower; its lower canines are not procumbent; the metacrista of M3 is U-shaped; the postmetacrista of M4 is present and the mandibular symphysis is shorter. This new material allows reconsideration of some dental traits proposed to diagnose the Proborhyaenidae such as the number of incisors and the open-rooted canines. 相似文献
155.
156.
157.
Rahman N Dunstan M Teare MD Hanks S Edkins SJ Hughes J Bignell GR Mancini G Kleijer W Campbell M Keser G Black C Williams N Arbour L Warman M Superti-Furga A Futreal PA Pope FM 《American journal of human genetics》2002,71(4):975-980
Juvenile hyaline fibromatosis (JHF) is an autosomal recessive condition characterized by multiple subcutaneous nodular tumors, gingival fibromatosis, flexion contractures of the joints, and an accumulation of hyaline in the dermis. We performed a genomewide linkage search in two families with JHF from the same region of the Indian state of Gujarat and identified a region of homozygosity on chromosome 4q21. Dense microsatellite analyses within this interval in five families with JHF who were from diverse origins demonstrate that all are compatible with linkage to chromosome 4q21 (multipoint LOD score 5.5). Meiotic recombinants place the gene for JHF within a 7-cM interval bounded by D4S2393 and D4S395. 相似文献
158.
Activation of pyk2/related focal adhesion tyrosine kinase and focal adhesion kinase in cardiac remodeling 总被引:8,自引:0,他引:8
Melendez J Welch S Schaefer E Moravec CS Avraham S Avraham H Sussman MA 《The Journal of biological chemistry》2002,277(47):45203-45210
Cellular remodeling during progression of dilation involves focal adhesion contact reorganization. However, the signaling mechanisms and structural consequences leading to impaired cardiomyocyte adhesion are poorly defined. These events were studied in tropomodulin-overexpressing transgenic mice that develop dilated cardiomyopathy associated with chronic elevation of intracellular calcium. Analysis of tropomodulin-overexpressing transgenic hearts by immunoblot and confocal microscopy revealed activation and redistribution of signaling molecules known to regulate adhesion. Calcium-dependent pyk2/related focal adhesion tyrosine kinase (RAFTK) showed changes in expression and phosphorylation state, similar to changes observed for a related downstream target molecule of pyk2/RAFTK termed focal adhesion kinase. Paxillin, the target substrate molecule for focal adhesion kinase phosphorylation, was redistributed in tropomodulin-overexpressing transgenic hearts with enhanced paxillin phosphorylation and cleavage. Certain aspects of the in vivo signaling phenotype including increased paxillin phosphorylation could be recapitulated in vitro using neonatal rat cardiomyocytes infected with recombinant adenovirus to overexpress tropomodulin. In addition, increasing intracellular calcium levels with ionomycin induced pyk2/RAFTK phosphorylation, and adenovirally mediated expression of wild-type pyk2/RAFTK resulted in increased phospho-pyk2/RAFTK levels and concomitant paxillin phosphorylation. Collectively, these results delineate a cardiomyocyte signaling pathway associated with dilation that has potential relevance for cardiac remodeling, focal adhesion reorganization, and loss of contractility. 相似文献
159.
Chrysanthemum: advances in tissue culture, cryopreservation, postharvest technology, genetics and transgenic biotechnology 总被引:8,自引:0,他引:8
Teixeira da Silva JA 《Biotechnology advances》2003,21(8):715-766
Members of the Chrysanthemum-complex include important floricultural (cut-flower) and ornamental (pot and garden) crops, as well as plants of culinary, medicinal and (ethno)pharmacological interest. The last 35 years have seen a tremendous emphasis on their in vitro tissue culture and micropropagation, while the latter 10–15 years has seen a surge in transformation experiments, all aimed at ameliorating aesthetic and growth characteristics of the plants. This review highlights all available literature that exists on ornamental Chrysanthemum in vitro cell, tissue and organ culture, micropropagation and transformation. 相似文献
160.
Zhu Y Nam J Humara JM Mysore KS Lee LY Cao H Valentine L Li J Kaiser AD Kopecky AL Hwang HH Bhattacharjee S Rao PK Tzfira T Rajagopal J Yi H Veena Yadav BS Crane YM Lin K Larcher Y Gelvin MJ Knue M Ramos C Zhao X Davis SJ Kim SI Ranjith-Kumar CT Choi YJ Hallan VK Chattopadhyay S Sui X Ziemienowicz A Matthysse AG Citovsky V Hohn B Gelvin SB 《Plant physiology》2003,132(2):494-505
Limited knowledge currently exists regarding the roles of plant genes and proteins in the Agrobacterium tumefaciens-mediated transformation process. To understand the host contribution to transformation, we carried out root-based transformation assays to identify Arabidopsis mutants that are resistant to Agrobacterium transformation (rat mutants). To date, we have identified 126 rat mutants by screening libraries of T-DNA insertion mutants and by using various “reverse genetic” approaches. These mutants disrupt expression of genes of numerous categories, including chromatin structural and remodeling genes, and genes encoding proteins implicated in nuclear targeting, cell wall structure and metabolism, cytoskeleton structure and function, and signal transduction. Here, we present an update on the identification and characterization of these rat mutants. 相似文献