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121.
Summary DNA fingerprints generated by the Jeffreys' probes, 33.6 and 33.15, indicated the presence of minisatellite-like sequences
in the red clover genome. The fingerprints generated by probe 33.6 gave less background and fewer but better defined bands
than those obtained with probe 33.15. Assay of a regenerative somaclonal variant (F49R) by DNA fingerprinting with probe 33.6
detected mutation that was unlinked to the regenerative trait. The fingerprints obtained under the applied conditions also
demonstrated genetic stability of consecutive generations of the regenerants in tissue culture. DNA fingerprints of F1 plants revealed that each polymorphic band was inherited from either one or the other parent. Both probes distinguished individual-specific
genotypes in seven cultivars of red clover. Greater variability in DNA fingerprints was detected between (V=0.899) than within
(0.417≤V≤0.548) cultivars. 相似文献
122.
Sally Badawi Feda E. Mohamed Divya Saro Varghese Bassam R. Ali 《Traffic (Copenhagen, Denmark)》2023,24(8):312-333
Endoplasmic reticulum-associated protein degradation (ERAD) is a stringent quality control mechanism through which misfolded, unassembled and some native proteins are targeted for degradation to maintain appropriate cellular and organelle homeostasis. Several in vitro and in vivo ERAD-related studies have provided mechanistic insights into ERAD pathway activation and its consequent events; however, a majority of these have investigated the effect of ERAD substrates and their consequent diseases affecting the degradation process. In this review, we present all reported human single-gene disorders caused by genetic variation in genes that encode ERAD components rather than their substrates. Additionally, after extensive literature survey, we present various genetically manipulated higher cellular and mammalian animal models that lack specific components involved in various stages of the ERAD pathway. 相似文献
123.
Joelle Vilamitjana-Amedee Reine Bareille Francois Rouais Arnold I. Caplan Marie-Francoise Harmand 《In vitro cellular & developmental biology. Animal》1993,29(9):699-707
Summary This study reports the selection and characterization of osteogenic precursors from human bone marrow which were isolated
by two “clonings” and successive subculturing. These cell lines express alkaline phosphatase activity. Gel electrophoresis
of [3H]-proline labeled cultures showed that the cloned cells produce only type I collagen. They synthetize osteocalcin and osteonectin.
They respond to 1,25 dihydroxy vitamin D3 by increasing osteocalcin synthesis and secretion, and to parathyroid hormone by increasing cyclic AMP synthesis. After the
third subculture in the absence of β-glycerophosphate, these cell lines formed lots of clusters which exhibit high alkaline
phosphatase activity and positive von Kossa staining. X-ray energy spectrum shows that these cells are surrounded by “budding”
structures containing calcium and phosphorus with a ratio Ca:P identical to those of pure hydroxyapatite. This process was
associated with45Ca uptake into the cells. All these data support the selection of osteogenic cells which may be of considerable clinical importance. 相似文献
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128.
Peatlands as scientific archives of past biodiversity 总被引:5,自引:0,他引:5
Keith E. Barber 《Biodiversity and Conservation》1993,2(5):474-489
Peat bogs preserve past biodiversity in a way which is unique among ecosystems, but the full realization of this, and the exploitation of the various records which are archived in the stratified layers of peat, is only now beginning. Present knowledge of peat formation in ombrotrophic or rain-fed bogs is reviewed and the many advantages of such systems as proxy-data sources are summarized. Some results of recent work involving pollen analysis and human impact, pollution histories, volcanic ash layers, plant macrofossils and the prospects for a detailed proxy-climate record are presented. The present vegetation of such bogs is only a very partial view of their past biodiversity; the conservation of the peat that remains must have a high priority. 相似文献
129.
An in vitro test method for general metal toxicity screening was designed, based on the cellular response to stress. The expression of a transfected human growth hormone gene sequence driven by the human heat-shock protein 70 promoter in NIH/3T3 cells was used as marker of noxious contact with metal compounds. Out of a series of31 metals, 17 were competentfor inducing this stress response system. According to the effective concentration and to the intensity of the response, three different clusters of positive compounds emerged and were ranked as strong, intermediate strength and weak inducers. These results correlated well with data from other in vivo and in vitro metal toxicity studies, including LD50 in mice. Apparently the positivelnegative compounds also fitted well with data from genotoxicity and carcinogenesis studies on metal salts.Abbreviations hGH
human growth hormone
- hsp70
70 kDa heat-shock protein 相似文献
130.
Fibronectin (FN) turnover and turnover changes induced by the anticancer drug Adriamycin (ADR) were measured in human mesangial cells (HMC) in vitro. HMC cultures synthesize cellular FN (2.2+-0.3% of totalprotein synthesis; n = 12) which is secreted and incorporated into a fibrillar extracellular matrix (ECM). A 24 hr incubation of HMC with ADR (0.5–5 g/ml) resulted in an accumulation of FN in the culture medium, with a maximum increase following 5 pglml(7.3+-2.3pg/cell vs. controls: 4.4+-1.9pg/cell; n= 10). Correspondingly, radioactively labeled immunoprecipitable FN was increased in a dosage-dependent manner in the culture medium up to 50% vs. controls. The incorporation of radioactively labeled FN into ECM was significantly increased following 2 g ADR/ml. In accordance, immunofZuorescence staining revealed an expansion ofpericellular FNfibers in cultures exposed to 2 g ADR/ml. Concomitant with the accumulation of extracelhlar FN, radioactively labeled FN in the cells was reduced by 22%. Qualitative characterization of FN patterns revealed a diminished number of degradation products in the culture medium ofADR-treated HMC. These data suggest thatADR interferes with the turnover of FN secreted by HMC in vitro in such a way that FN accumulates extracellularly. This in turn leads to a reduced FN synthesis. These findings are compatible with a loss of urinary FN degradation products accompanying the onset ofproteinuria in ADR-treated rats.Abbreviations ADR
adriamycin
- BSA
bovine serum albumin
- DTT
dithiothreitol
- ECM
extracellular matrix
- EDTA
ethylenediamine tetraacetic acid disodium salt
- ELISA
enzyme-linked immunosorbent assay
- FCS
fetal calf serum
- FITC
fluorescein isothiocyanate
- FN
fibronectin
- HMC
human mesangial cell
- PBS
phosphate buffered saline
- PMSF
phenylmethylsulfonyl fluoride
- SDS
sodium dodecyl sulfate
- SDS-PAGE
SDS-polyacrylamide gel electrophoresis 相似文献