GLORIA

GEOMAR Library Ocean Research Information Access

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Human bone cell enzyme expression and cellular heterogeneity: Correlation of alkaline phosphatase enzyme activity with cell cycle (1990)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 144 (1990), S. 115-121 
    Details
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Alkaline phosphatase, long implicated in biomineralization, is a feature of the osteoblast phenotype. Yet in cultured bone cells, only a fraction stain positive histochemically. To determine whether osteoblast enzyme expression reflects cellular heterogeneity with respect to cell cycle distribution or length of time in culture, the activities of alkaline phosphatase, tartrate-resistant and -sensitive acid phosphatases, and non-specific esterases were assayed kinetically and histo-chemically. In asynchronous subconfluent cultures, 〈 15% of the cells stained positive and assayed activity was 0.04 IU/106 cells/cm2. After 1 week, the percent of alkaline phosphatase positive-staining cells increased 5-fold, while activity increased 10-fold. Non-specific esterases and tartrate-sensitive acid phosphatase were constitutive throughout time in culture, whereas tartrate-resistant acid phos-phatase activity appeared after 2 weeks. Cell cycle analysis of human bone cells revealed a growth fraction of 80%, an S phase of 8.5 h, G2 + 1/2 M of 4 h, and a G1 of 25-30 h. In synchronous cultures induced by a thymidine-aphidicolin protocol, alkaline phosphatase activity dropped precipitously at M phase and returned during G1. A majority of the alkaline phosphatase activity lost from the cell surface at mitosis was recovered in the medium. Tartrate-sensitive acid phos-phatase and non-specific esterase levels were relatively stable throughout the cell cycle, while tartrate-resistant acid phosphatase activity was not assavable at the density used in synchronous cultures. From these data, variations in alkaline phosphatase activity appear to reflect the distribution of cells throughout the cell cycle.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcp.1041440115
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    In vitro expression of osteoblastic markers in cells isolated from normal fetal and postnatal human bone and from bone of patients with osteogenesis imperfecta (1993)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 157 (1993), S. 439-444 
    Details
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: We studied the expression of osteoblastic markers in cultured cells isolated from the bone of 15 patients with different clinical forms of osteogenesis imperfecta (OI) and of seven fetal and postnatal controls. Cultured bone cells of ten OI patients produced abnormal collagen type I. Similar to controls, OI bone cells produced predominantly collagen type I with traces of collagen types III and V. The 1,25(OH)2 vitamin D3-stimulated synthesis of osteocalcin, a specific osteoblastic marker protein, was similar in OI bone cells and age-matched controls. Bone cells from fetal controls and from patients with the perinatal lethal OI type II produced less osteocalcin than bone cells from postnatal controls and surviving OI patients. OI bone cells responded to parath.yroid hormone (PTH) by increased production of cAMP similar to controls. Bone cells from fetal controls and from OI type II donors showed a decreased response to PTH. Activity of the bone-liver-kidney isoenzyme alkaline phosphatase (AP) was detected in all control and OI bone cells. The expression of all osteoblastic markers was similar in bone cells producing abnormal collagen type I. These observations show that OI bone cells in vitro express a pattern of osteoblastic markers similar to age-matched control bone cells indicating that osteoblastic differentiation is not altered by the underlying defects of collagen type I metabolism in OI bone cells. © 1993 Wiley-Liss, Inc.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcp.1041570302
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Age-related changes in hyaluronan, proteoglycan, collagen, and osteonectin synthesis by human bone cells (1992)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 151 (1992), S. 215-227 
    Details
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Human bone cells grown in culture, representative of a preosteoblastic stage of maturation, produce an extracellular matrix composed of collagen several noncollagenous glycoproteins, hyaluronan, and four distinct proteoglycans (PGs). The influence of donor age on the levels of expression of these molecules in vitro has not been well characterized. In this study, human bone cells derived from sources ranging from fetal to 60-year-old donors were grown in culture, radiolabeled for 24 h, and the amount of incorporation of [35S]sulfate into PGs, [3H]glucosamine into hyaluronan, [3H]leucine/proline into osteonectin, and [3H]proline into collagen was determined. Cell proliferation was most rapid in fetal-derived bone cells and decreased with increasing age. Total protein and PG synthesis also decreased with increasing age, falling to 1/3 and 1/4, respectively, of fetal levels after age 30. A large chondroitin sulfate PG (Mr ∼ 600,000 Da) was the major fetal PG and its levels were highly correlated with cellular proliferation. [3H]Collagen and [35S]decorin levels increased with the increasing age of the donor, reached a maximum in puberty-derived cells, and decreased to 1/3 maximal levels after age 20. The heparan sulfate PG (Mr ∼ 400,000 Da) exhibited steadystate levels regardless of donor age. [3H]Osteonectin and [35S]biglycan levels were high in fetal-derived cells and in cells derived from pubescent donors. The percentage of collagen and four proteoglycans associated with the cell layer pool changed with donor age. All fetal-derived PG core proteins possessed more N- and O-linked oligosaccharides than newborn or adult derived PGs. © 1992 Wiley-Liss, Inc.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcp.1041510202
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Analysis of the THR4 region on chromosome III of the yeast Saccharomyces cerevisiae (1990)
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 6 (1990), S. 353-361 
    Details
    ISSN: 0749-503X
    Keywords: Threonine metabolism ; amino acid biosynthesis ; homologous domains ; chromosome III ; gene organisation ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The gene encoding theonine synthase (THR4) from the yeast Saccharomyces cerevisiae was cloned by complementation of a thr4 mutant. This gene was also found on a lambda clone (5239) consisting of a fragment of chromosome III inserted in the vector lambda MG3. The THR4 gene encodes a protein of 514 amino acids (M.W. 58 kDa), which has extensive homologies with E. coli threonine synthase (thrC) and B. subtilis threonine synthase. The 5′ flanking region of the gene contains three regulatory sequences. [TGACT(C)] for the general amino acid control (GCN).About 130 bp downstream of the THR4 gene another open reading frame (563 amino acids) is found in the opposite orientation. This may imply that this open reading frame, called CTR86, shares a terminator region with THR4. The function of the protein encoded by CTR86 is not yet clear, but the fact that the upstream region contains a GCN4 responsive site that the gene product may also be involved in amino acid biosynthesis.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/yea.320060408
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Molecular analysis of yeast chromosome II between CMD1 and LYS2: The excision repair gene RAD16 located in this region belongs to a novel group of double-finger proteins (1992)
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 8 (1992), S. 397-408 
    Details
    ISSN: 0749-503X
    Keywords: Saccharomyces cerevisiae ; chromosome II ; RAD16 ; DNA helicase ; double-finger motif ; DNA excision repair ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: We have analysed a region some 30 kb centromere distal form PHO5 on the right arm of yeast chromosome II and determined the nucleotide sequence of a 8.95 kb DNA segment from this region. By this analysis we were able to derive the precise location and the transcriptional orientation of CMD1, ALG1, SSN6 and LYS2. An open reading frame of 2370 bp was locatlized between SSN6 and LYS2, which has recently been identified (Schild et al., 1991) to be the RAD16 gene. The putative gene product, 790 amino acids in length, reveals several interesting freatures. It contains a nuclear target singnature and shares several blocks of similarity with the yeast recombinational repair protein RAD54 and the nuclear factor SNF2 (SW12), which is required for teh transcriptioal activation of a number of yeast genes. The similarity blocks in these three proteins are reminiscent of those found in the helicase superfamily. Furthrmore, RAD16 contains a novel ‘double-finger’ motif, which has been encountered in a variety of proteins from different organisms that are suggested to interact with DNA and are involved in diverse functions including site-specific recombination, DNA repair, and transcriptional regulation. The putative gene product of RAD16 then is the first example of a proteins in which the novel double-finger motif is found to be combined with a poteintial DNA helicase framework.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/yea.320080507
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Identification of a set of yeast genes coding for a novel family of putative ATPases with high similarity to constituents of the 26S protease complex (1994)
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 10 (1994), S. 1141-1155 
    Details
    ISSN: 0749-503X
    Keywords: Multi-gene family ; ATPases ; proteasome ; S. cerevisiae ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: There is accumulating evidence for a large, highly conserved gene family of putative ATPases. We have identified 12 different members of this novel gene family (the YTA family) in yeast and determined the nucleotide sequences of nine of these genes. All of the putative gene products are characterized by the presence of a highly conserved domain of 300 amino acids containing specialized forms of the A and B boxes of ATPases. YTA1, YTA2, YTA3 and YTA5 exhibit significant similarity to proteins involved in human immunodeficiency virus Tat-mediated gene expression but more significantly to subunits of the human 26S proteasome. YTA1 and YTA2 are essential genes in yeast. Remarkably, the cDNA of human TBP-1 can compensate for the loss of YTA1. Preliminary experiments indicate that YTA1 is a component of the 26S protease complex from yeast. Our findings lead us to propose that YTA1, YTA2, YTA3 and YTA5 function as regulatory subunits of the yeast 26S proteasome. YTA10, YTA11 and YTA12 share significant homology with the Escherichia coli FtsH protein, and together with YTA4 and YTA6 may constitute a separate subclass within this family of putative ATPases.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/yea.320100903
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    II. Yeast sequencing reports. Analysis of a 70kb region on the right arm of yeast chromosome II (1994)
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 10 (1994), S. 1363-1381 
    Details
    ISSN: 0749-503X
    Keywords: Saccharomyces cerevisiae ; chromosome II ; ORFs ; predictable functions ; regulatory elements ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: In the framework of the EC programme for sequencing yeast chromosome II, we have determined the nucleotide sequence of a 70 kb region. Subsequent analysis revealed 35 open reading frames, 14 of which correspond to known yeast genes. From structural parameters and/or similarity searches with entries in the current data libraries, a preliminary functional assessment of several of the putative novel gene products can be made. The gene density in this region amounts to one gene in 1.98 kb. Coding regions occupy 75% of the total DNA sequence. Within the intergenic regions, potential regulatory elements can be predicted. The data obtained here may serve as a basis for a more detailed biochemical analysis of the novel genes. The complete nucleotide sequence of the 70 kb segment as depicted in Figure 1 has been deposited in the EMBL data library under Accession Number X78993.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/yea.320101014
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...