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1.
Adenylyl cyclase activity plays a central role in the regulation of most cellular processes. At least eight different adenylyl cyclases have been identified, which are endowed with various and sometimes opposing regulatory properties. Recently we have localized the human genes encoding two of these adenylyl cyclases: the gene for type 11 adenylyl cyclase is located on chromosome 2 (sub-band 2p15.3), the gene for type VIII is located on chromosome 8 (sub-band 8824.2). More recently the type I gene has been located on chromosome 7 (sub-band 7pl2–7p13). Using in situ hybridization, we have now localized the genes for three other adenylyl cyclases: the type III gene has been localized on chromosome 2 in the sub-band 2p22–2p24, the type V gene on chromosome 3 at position 3q13.2–3q21, and the type VI gene on chromosome 12 at position 12q12–12q13. It therefore appears that all adenylyl cyclase genes, known at present are located on different chromosomes and thus are likely to be independently regulated.  相似文献   

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Ildikó Nagy 《FEBS letters》2008,582(29):4003-4007
Cochlin is colocalized with type II collagen in the extracellular matrix of cochlea and has been suggested to interact with this collagen. Here we show that the second von Willebrand type A domain of cochlin has affinity for type II collagen, as well as type I and type IV collagens whereas the LCCL-domain of cochlin has no affinity for these proteins. The implications of these findings for the mechanism whereby cochlin mutations cause the dominant negative DFNA9-type hearing loss are discussed.

Structured summary

MINT-6796048:
type I collagen (uniprotkb:P02452) binds (MI:0407) to cochlin-vWA2 uniprotkb:O43405) by surface plasmon resonance (MI:0107)
MINT-6796166:
type III collagen (uniprotkb:P02462) binds (MI:0407) to cochlin-vWA2 (uniprotkb:O43405) by surface plasmon resonance (MI:0107)
MINT-6796062:
type II collagen (uniprotkb:P02458) binds (MI:0407) to cochlin-vWA2 (uniprotkb:O43405) by surface plasmon resonance (MI:0107)
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The FBJ osteosarcoma (a virus-induced osteosarcoma named after its discoverers, Finkel, Biskis, and Jinkins) contains an extensive extracellular matrix. Collagens were extracted by digestion with pepsin in dilute acetic acid from tumors grown in lathyritic mice and fractionated by differential salt precipitation, yielding five fractions. Fraction 1 (precipitated at acidic 0.7 M and neutral 2.0 M NaCl) gave rise mainly to alpha 1(III) chain on phosphocellulose column chromatography. The alpha 1(III) chain was identified by its typical behavior on interrupted electrophoresis and analysis of the CNBr-cleaved peptides. The alpha 1(III) chain of the FBJ tumor had a high content of hydroxylysine and neutral saccharide. Fraction 2 (precipitated at acidic 0.7 M and neutral 4.5 M NaCl) yielded alpha 1(I) and alpha 2(I) chains on the phosphocellulose column from which alpha 1(I) was eluted as a broad peak, conceivably reflecting a high content of hydroxylysine and neutral saccharide. Fraction 4 (precipitated at acidic 1.2 M and neutral 4.5 M NaCl) yielded type V collagen, which also featured an exceptionally high content of neutral saccharide (Yamagata, S., et al. (1982) Biochem. Biophys. Res. Commun. 105, 1208-1214). The proportions of type I, type I trimer, type III, and type V collagens extracted by pepsin digestion from FBJ tumor were calculated to be 33, 29, 26, and 12%, respectively. The FBJ tumor is free from invasion by blood vessels, shows no deposition of calcium, and thus has the appearance of cartilage. But type II collagen, a specific gene product of cartilage, could not be identified in any of the fractions analyzed. Contrary to its appearance, collagen type analyses indicate that FBJ osteosarcoma is literally induced from osteogenic cells.  相似文献   

5.
Differential ontogeny of type 1 and type 2 benzodiazepine receptors   总被引:9,自引:0,他引:9  
The postnatal development of Type 1 and Type 2 benzodiazepine receptors in rat cerebral cortex was studied using CL 218,872, a novel triazolopyridazine. On postnatal day 1 most 3H-flunitrazepam binding sites appeared to be Type 2 receptors, which increased rapidly during the first week of life and reached adult levels by 3–4 weeks of age. Type 1 receptors, on the other hand, represented only a small percentage of the binding sites on postnatal day 1 and did not begin to increase in number until approximately 7–16 days of age. These results demonstrate a differential postnatal development of two sub-populations of benzodiazepine receptors.  相似文献   

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猪I型与II型干扰素的克隆、表达及抗病毒活性比较   总被引:1,自引:0,他引:1  
干扰素(IFN)是由多种细胞受病毒感染或其他生物诱导剂刺激而产生的天然蛋白质,主要功能为抗病毒增殖、调节免疫反应和激活免疫细胞等。本研究克隆并测序了猪干扰素(PoIFN)α、γ、αγ及ω基因。构建原核表达载体pET-His/PoIFN-α、pET-His/PoIFN-γ、pET-His/PoIFN-αγ和pET-His/PoIFN-ω,转化大肠杆菌Rosetta(DE3)进行表达,经纯化、复性得到具有生物学活性的蛋白。用细胞病变抑制法在Marc-145/PRRSV、Marc-145/VSV、PK-15/VSV、Vero/VSV、MDBK/VSV系统上进行抗病毒活性测定,结果表明猪α和αγ融合干扰素有较为显著的抗病毒活性,抗PRRSV活性高达108U/mg;猪γ干扰素活性效价约为α干扰素的1/2到1/3;猪ω干扰素几乎未检测到抗病毒活性,需进一步验证。本研究对干扰素在抗病毒、提高机体免疫方面的应用提供了理论依据。  相似文献   

11.
Recently, the notion of diversity, which is directed towards (effective) numbers of types (states of a trait such as species and genotypes), is increasingly used as an umbrella term akin to “variation”, thus including classical metrics of dispersion among others. This is probably due to the growing interest in functional aspects of variation which involve variable differences between types. Though the traditional notion of diversity does not cover these aspects, it shows up in many interpretations. To overcome this ambiguity, the traditional notion of diversity is extended in this paper to include variable differences with emphasis on their general significance as structuring features. For this purpose, structure is conceived to be captured by the representation of types via variable differences and abundances. Structural diversity then results from application of traditional measures of diversity to the relative structural representations of types in addition to their relative abundances. Since diversity as effective number of types alone provides no information about their mutual distinctness and the range covered by them, connections to measures of dispersion are indispensable. This is considered via two approaches that rely on dispersion characteristics and one approach that allows for an assessment of structural diversity for controlled levels of type distinctness. Effects of structure on dispersion and diversity are analyzed. The use of the approaches for discovering rarely considered characteristics of phylogenetic structure is demonstrated.  相似文献   

12.
Molecular defects of type III procollagen in Ehlers-Danlos syndrome type IV   总被引:10,自引:0,他引:10  
Summary Fibroblasts from most patients with Ehlers-Danlos syndrome (EDS) type IV, a disorder characterized by fragility of skin, blood vessels, and internal organs, secrete reduced amounts of type III procollagen. In 7 of 8 cell strains analyzed, we found evidence of structural defects in half of the type III procollagen chains synthesized, such as deletions or bona fide amino acid substitutions, which cause delayed formation and destabilization of the collagen triple helix and, as a consequence, reduced secretion of the molecule. The data suggest that EDS type IV is often caused by heterozygosity for mutations at the COL3A1 locus, which affect the structure of type III procollagen. The triple-helical region of the molecule, like the homologous region of type I procollagen, appears to be particularly vulnerable.Parts of this work have been presented at the 2nd International Conference on Molecular Biology and Pathology of Matrix, Philadelphia, June 15–18, 1988  相似文献   

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孢子丝菌病是申克孢子丝菌引起的皮肤、皮下及附近淋巴管的慢性结节或溃疡性病变。最早由美国的Baltimore报道了首例,1898年Schenck由上肢多发性脓肿中分离出病原菌,称为Sporotrichumsp.。1900年Hektoen和Perkins报道了第2例,将病原菌命名为SporotrixSchenckii。1920年西泽等报道了日本首例。1916年刁德信报道了我国首例。以后世界各国陆续报道,为世界性分布。  相似文献   

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Usefulness of adenoviral vectors derived from human adenovirus (HAd) type 5 (HAd5) is mainly limited by wide prevalence of preexisting anti-HAd5 immunity as well as non-specific tissue tropism of these vectors. As an alternative, non-human adenoviral vectors including bovine adenovirus type 3 (BAd3) are currently being investigated. Non-prevalence of BAd3 in humans and its ability to evade preexisting HAd immunity are some of the features that make BAd3 a promising vector for human gene delivery. BAd3 appears to have a tissue tropism distinct from that of HAd5 and also the repertoire of cells efficiently transduced by BAd3 is different. We performed antibody-mediated receptor blocking experiments to show that BAd3 internalization was independent of coxsackievirus-adenovirus receptor, the primary determinant of HAd5 tropism, or integrin alpha(v)beta3, a secondary molecule involved in HAd5 entry. Using homologous and heterologous knob-mediated competition assays with recombinant knobs of HAd5, porcine adenovirus type 3 (PAd3), or BAd3, we observed that BAd3 internalization was independent of the primary receptors of HAd5 and PAd3. These results provide support for further exploration of BAd3 vectors for designing targeted vectors for human gene therapy.  相似文献   

17.
Polysaccharides extracted from Z3III streptococci either with formamide or with dilute hydrochloric acid or isolated from the growth medium could be fractionated in type III- and group Z3 antigens by alcohol precipitation. No good separation could be obtained from TCA extracts. When the same extractions and fractionations were applied to streptococci carrying type III antigen, but different group antigens, good separations were again obtained of all formamide extracts, but not of all hydrochloric acid extracts. The group antigens showed a rhamnose content of at least 50% and contained hexosamines. Type III antigens contained mainly rhamnose, glucose and galactose in relative amounts of approximately 1:2:3. Analysis of the methylated type III antigen suggests it to be a polysaccharide with a linear structure. Type III antigen isolated from the medium was characterized not only by a different sugar ratio, but also by its fucose content of 20%. In some cases the purified polysaccharides contained considerable amounts of glycogen-like material. Partial acid hydrolysis of the type III antigen extracted with formamide yielded a great number of oligosaccharides. Analyses, inhibition reactions and methylation studies gave indications that the most probable structure of a determinant group of type III antigen is β-glucosyl-(1-6)-galactosyl-(1-6)-galactosyl-(1-3)-rhamnose. The possibility of the existence of a second determinant group is discussed.  相似文献   

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Type IX collagen functions in covalent cross-linkage to type II collagen in cartilage (Eyre, D. R., Apone, S., Wu, J. J., Ericsson, L. H., and Walsh, K. A. (1987) FEBS Lett. 220, 337-341). To understand this molecular relationship better, an analysis of all cross-linking sites labeled by [3H]borohydride was undertaken using the protein prepared from fetal bovine cartilage. Sequence analysis of tryptic peptides containing the 3H-labeled cross-links showed that each of the chains of type IX collagen, alpha 1(IX), alpha 2(IX), and alpha 3(IX), contained a site of cross-linking at the amino terminus of the COL2 triple-helix to which the alpha 1(II)N-telopeptide could bond. The alpha 3(IX)COL2 domain alone also had an attachment site for the alpha 1(II)C-telopeptide. The distance between the alpha 1(II)N-telopeptide and alpha 1(II)C-telopeptide interaction sites, 137 residues, is equal to the length of the hole zone (0.6D) in a type II collagen fibril. This implies an antiparallel type II to type IX cross-linking relationship. Peptide analysis also revealed an unknown amino acid sequence linked to the COL2 cross-linking domains in both the alpha 1(IX) and alpha 3(IX) chains. Using antibodies to this novel peptide, its origin in the collagen alpha 3(IX)NC1 domain was established. In summary, the results confirm extensive covalent cross-linking between type IX and type II collagen molecules and reveal the existence of type IX-type IX bonding. These data provide a molecular basis for the proposed function of type IX collagen as a critical contributor to the mechanical stability and resistance to swelling of the collagen type II fibril framework of cartilage.  相似文献   

19.
Physical maps of bovine papillomavirus type 1 and type 2 (BPV-1 and BPV-2) DNA were constructed from analysis of the electrophoretic mobilities of restriction endonuclease cleavage fragments from dual digests. BPV-1 DNA was sensitive to Hind III, HindIII, EcoRI, HpaI, AND BamHI, with all but HindII yielding single scissions. BPV-2 DNA was resistant to EcoRI, and HindIII had one cleavage site whereas HpaI, BamHI, and HindII yielded multiple fragments. Of four BPV-1 isolates examined, DNA from one isolate was resistant to HindIII, and another DNA isolate was resistant to BamHI. The three BPV-2 isolates examined were uniformly sensitive to the restriction endonucleases employed.  相似文献   

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