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The Rh blood group system is of clinical importance in blood transfusion and as the cause of hemolytic disease of the newborn. Other than their role as carriers of Rh antigens, very little is known about the function of the Rh polypeptides. As a first step to generate an animal model system in which to study the structure and function of Rh, and to extend the phylogenetic analysis of RH genes, the Rh homologue from Mus musculus was characterized. Comparison of RH from humans and mice revealed 71 and 58% sequence identity at the nucleotide and amino acid levels, respectively. Mouse Rh mRNA encodes a protein which is 1 amino acid longer (418 aa) than that of human (417 aa). Rh protein was detected in mouse erythrocyte membranes and was comparable in size to human Rh. Mouse erythrocytes do not show serologic reactivity with human Rh antibodies, probably because the greatest divergence between the mouse and the human genes was seen in the predicted extracellular loops, while the transmembrane regions were more conserved. The mouse RH locus consists of only one gene, which is important for future genetic manipulation and which also indicates that the RH gene duplication seen in humans has occurred since the mammalian radiation.  相似文献   
203.
BackgroundLow fruit and vegetable (FV) intake is a leading risk factor for chronic disease globally as well as in the United States. Much of the population does not consume the recommended servings of FV daily. This paper describes the development of psychosocial measures of FV intake for inclusion in the U.S. National Cancer Institute’s 2007 Food Attitudes and Behaviors Survey.MethodsThis was a cross-sectional study among 3,397 adults from the United States.Scales included conventional constructs shown to be correlated with fruit and vegetable intake (FVI) in prior studies (e.g., self-efficacy, social support), and novel constructs that have been measured in few- to- no studies (e.g., views on vegetarianism, neophobia). FVI was assessed with an eight-item screener. Exploratory factor analysis, Cronbach’s alpha, and regression analyses were conducted.ResultsPsychosocial scales with Cronbach’s alpha ≥0.68 were self-efficacy, social support, perceived barriers and benefits of eating FVs, views on vegetarianism, autonomous and controlled motivation, and preference for FVs. Conventional scales that were associated (p<0.05) with FVI were self-efficacy, social support, and perceived barriers to eating FVs. Novel scales that were associated (p<0.05) with FVI were autonomous motivation, and preference for vegetables. Other single items that were associated (p<0.05) with FVI included knowledge of FV recommendations, FVI “while growing up”, and daily water consumption.ConclusionThese findings may inform future behavioral interventions as well as further exploration of other potential factors to promote and support FVI.  相似文献   
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Activating mutations within fibroblast growth factor receptor 3 (FGFR3), a receptor tyrosine kinase, are responsible for human skeletal dysplasias including achondroplasia and the neonatal lethal syndromes thanatophoric dysplasia types I and II. Several of these same FGFR3 mutations have also been identified somatically in human cancers, including multiple myeloma, bladder carcinoma, and cervical cancer. The molecular pathways exploited by FGFR3 to stimulate abnormal proliferation during neoplasia are unclear. The nonreceptor protein-tyrosine kinase Pyk2 (proline-rich tyrosine kinase 2) has been shown previously to regulate apoptosis in multiple myeloma cells. Here we describe a novel interaction between FGFR3 and Pyk2, mediated by the juxtamembrane domain of FGFR3 and the kinase domain of Pyk2. Within the FGFR family, Pyk2 also interacted significantly with FGFR2. Overexpression of Pyk2 alone led to its spontaneous activation and tyrosine phosphorylation, resulting in activation of Stat5B, indicated by the reporter GFP-Stat5B. These effects were completely dependent upon Tyr(402), the autophosphorylation site of Pyk2, which allows recruitment of Src family members for further activating phosphorylations at other sites on Pyk2. In the presence of activated FGFR3, the activation of Pyk2 itself became independent of Tyr(402), indicating that FGFR3 activation circumvents the requirement for c-Src recruitment at Tyr(402) of Pyk2. We also examined the role of the tyrosine phosphatase Shp2 in antagonizing Pyk2 activation. Taken together, these results suggest that signaling pathways regulated by FGFR3 may converge with Pyk2-dependent pathways to provide maximal activation of Stat5B.  相似文献   
206.
Burch AD  Weller SK 《Journal of virology》2004,78(13):7175-7185
Herpes simplex virus type 1 (HSV-1) encodes a portal protein that forms a large oligomeric structure believed to provide the conduit for DNA entry and exit from the capsid. Chaperone proteins often facilitate the folding and multimerization of such complex structures. In this report, we show that cellular chaperone proteins, components of the 26S proteasome, and ubiquitin-conjugated proteins are sequestered in discrete foci in the nucleus of the infected cell. The immediate-early viral protein ICP0 was shown to be necessary to establish these foci at early times during infection and sufficient to redistribute chaperone molecules in transfected cells. Furthermore, we found that not only is the portal protein, UL6, localized to these sites during infection, but it is also a substrate for ubiquitin modification. Our results suggest that HSV-1 has evolved an elegant mechanism for facilitating protein quality control at specialized foci within the nucleus.  相似文献   
207.
The structures of xyloglucans from several plants in the subclass Asteridae were examined to determine how their structures vary in different taxonomic orders. Xyloglucans, solubilized from plant cell walls by a sequential (enzymatic and chemical) extraction procedure, were isolated, and their structures were characterized by NMR spectroscopy and mass spectrometry. All campanulids examined, including Lactuca sativa (lettuce, order Asterales), Tenacetum ptarmiciflorum (dusty miller, order Asterales), and Daucus carota (carrot, order Apiales), produce typical xyloglucans that have an XXXG-type branching pattern and contain alpha-d-Xylp-, beta-D-Galp-(1-->2)-alpha-D-Xylp-, and alpha-L-Fucp-(1-->2)-beta-D-Galp-(1-->2)-alpha-D-Xylp- side chains. However, the lamiids produce atypical xyloglucans. For example, previous analyses showed that Capsicum annum (pepper) and Lycopersicon esculentum (tomato), two species in the order Solanales, and Olea europaea (olive, order Lamiales) produce xyloglucans that contain arabinosyl and galactosyl residues, but lack fucosyl residues. The XXGG-type xyloglucans produced by Solanaceous species are less branched than the XXXG-type xyloglucan produced by Olea europaea. This study shows that Ipomoea pupurea (morning glory, order Solanales), Ocimum basilicum (basil, order Lamiales), and Plantago major (plantain, order Lamiales) all produce xyloglucans that lack fucosyl residues and have an unusual XXGGG-type branching pattern in which the basic repeating core contains five glucose subunits in the backbone. Furthermore, Neruim oleander (order Gentianales) produces an XXXG-type xyloglucan that contains arabinosyl, galactosyl, and fucosyl residues. The appearance of this intermediate xyloglucan structure in oleander has implications regarding the evolutionary development of xyloglucan structure and its role in primary plant cell walls.  相似文献   
208.
All Neisseria live in association with host cells, however, little is known about the genetic potential of nonpathogenic Neisseria species to express attachment factors such as pili. In this study, we demonstrate that type IV pilin-encoding genes are present in a wide range of Neisseria species. N. sicca, N. subflava, and N. elongata each contain two putative pilE genes arranged in tandem, while single genes were identified in N. polysaccharea, N. mucosa, and N. denitrificans. Neisserial pilE genes are highly diverse and display features consistent with a history of horizontal gene transfer.  相似文献   
209.
Previous studies in native tissues have produced conflicting data on the localization and metabolic fate of WT and deltaF508 cystic fibrosis transmembrane regulator (CFTR) in the lung. Combining immunocytochemical and biochemical studies utilizing new high-affinity CFTR mAbs with ion transport assays, we examined both 1) the cell type and region specific expression of CFTR in normal airways and 2) the metabolic fate of deltaF508 CFTR and associated ERM proteins in the cystic fibrosis lung. Studies of lungs from a large number of normal subjects revealed that WT CFTR protein localized to the apical membrane of ciliated cells within the superficial epithelium and gland ducts. In contrast, other cell types in the superficial, gland acinar, and alveolar epithelia expressed little WT CFTR protein. No deltaF508 CFTR mature protein or function could be detected in airway specimens freshly excised from a large number of deltaF508 homozygous subjects, despite an intact ERM complex. In sum, our data demonstrate that WT CFTR is predominantly expressed in ciliated cells, and deltaF508 CFTR pathogenesis in native tissues, like heterologous cells, reflects loss of normal protein processing.  相似文献   
210.
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