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Timothy J. Strabala Sebastian Y. Bednarek Gregory Bertoni Richard M. Amasino 《Molecular & general genetics : MGG》1989,216(2-3):388-394
Summary A 1.9 kb clone of the T-DNA region of the Agrobacterium tumefaciens Ti plasmid Bo542 which exhibited homology to the isopentenyl transferase (ipt) locus of pTiA6 was identified by low stringency DNA hybridization. Introduction of this segment of pTiBo542 DNA into cells of Nicotiana tabacum or N. glauca caused tumor formation in vivo, and allowed hormone independent growth in vitro. Furthermore, this DNA segment complemented ipt mutant strains of A. tumefaciens, restoring their ability to cause tumors on Kalanchöe leaves and tomato stems. The complete DNA sequence of this segment has been determined, revealing an open reading frame homologous to other known Agrobacterium ipt genes. 相似文献
3.
G. Bertoni T. Torresani E. M. Schraner P. Wild 《Virchows Archiv. B, Cell pathology including molecular pathology》1988,55(1):31-37
The responsiveness of parathyroid cells in insulin deficient and short-term diabetic rats was investigated by morphometric analysis. Insulin deficiency was produced by intravenous injection of D-mannoheptulose and short-term (7 days) diabetes mellitus by intraperitoneal application of streptozotocin. Parathyroid glands were stimulated for parathyroid hormone secretion by decreasing the serum calcium concentration through intravenous infusion of EGTA. Parathyroid cells of controls, insulin deficient, and short-term diabetic rats responded to reduced serum calcium by a 45% increase of the cell surface area. This increase is assumed to be the result of the membrane-bound transport of parathyroid hormone from the Golgi complex and secretory granules to the plasma membrane and subsequent exocytic release of parathyroid hormone induced by the low serum calcium concentration. Therefore, the unimpaired increase in the cell surface area of parathyroid cells in insulin deficient and short-term diabetic rats indicates that insulin does not modulate the release of parathyroid hormone. It is also considered likely that synthesis of parathyroid hormone is not suppressed in short-term diabetes but that fat metabolism is disturbed leading to accumulation of lipid vacuoles. 相似文献
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Genetic variation at the Major Histocompatibility Complex locus DQ beta was
analyzed in 233 beluga whales (Delphinapterus leucas) from seven
populations: St. Lawrence Estuary, eastern Beaufort Sea, eastern Chukchi
Sea, western Hudson Bay, eastern Hudson Bay, southeastern Baffin Island,
and High Arctic and in 12 narwhals (Monodon monoceros) sympatric with the
High Arctic beluga population. Variation was assessed by amplification of
the exon coding for the peptide binding region via the polymerase chain
reaction, followed by either cloning and DNA sequencing or single-stranded
conformation polymorphism analysis. Five alleles were found across the
beluga populations and one in the narwhal. Pairwise comparisons of these
alleles showed a 5:1 ratio of nonsynonymous to synonymous substitutions per
site leading to eight amino acid differences, five of which were
nonconservative substitutions, centered around positions previously shown
to be important for peptide binding. Although the amount of allelic
variation is low when compared with terrestrial mammals, the nature of the
substitutions in the peptide binding sites indicates an important role for
the DQ beta locus in the cellular immune response of beluga whales.
Comparisons of allele frequencies among populations show the High Arctic
population to be different (P < or = .005) from the other beluga
populations surveyed. In these other populations an allele, Dele-DQ
beta*0101-2, was found in 98% of the animals, while in the High Arctic it
was found in only 52% of the animals. Two other alleles were found at high
frequencies in the High Arctic population, one being very similar to the
single allele found in narwhal.
相似文献
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Cora E. Lewis John P. Bantle Alain G. Bertoni George Blackburn Frederick L. Brancati George A. Bray Lawrence J. Cheskin Jeffrey M. Curtis Caitlin Egan Mary Evans John P. Foreyt Siran Ghazarian Bethany Barone Gibbs Stephen P. Glasser Edward W. Gregg Helen P. Hazuda Louise Hesson James O. Hill Edward S. Horton Van S. Hubbard John M. Jakicic Robert W. Jeffery Karen C. Johnson Steven E. Kahn Abbas E. Kitabchi Dalane Kitzman William C. Knowler Edward Lipkin Sara Michaels Maria G. Montez David M. Nathan Ebenezer Nyenwe Jennifer Patricio Anne Peters Xavier Pi‐Sunyer Henry Pownall David M. Reboussin Donna H. Ryan Thomas A. Wadden Lynne E. Wagenknecht Holly Wyatt Rena R. Wing Susan Z. Yanovski 《Obesity (Silver Spring, Md.)》2020,28(2):247-258
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M. Zavatti E. Resca L. Bertoni T. Maraldi M. Guida G. Carnevale A. Ferrari A. De Pol 《Life sciences》2013,92(20-21):993-1003
AimsThe phytoestrogen Ferutinin plays an important role in prevention of osteoporosis caused by ovariectomy-induced estrogen deficiency in rats, but there is no evidence of its effect on osteoblastic differentiation in vitro. In this study we investigated the effect of Ferutinin on proliferation and osteoblastic differentiation of two different human stem cells populations, one derived from the amniotic fluid (AFSCs) and the other from the dental pulp (DPSCs).Main methodsAFSCs and DPSCs were cultured in a differentiation medium for 14 or 21 days with or without the addition of Ferutinin at a concentration ranging from 10? 11 to 10? 4 M. 17β-Estradiol was used as a positive drug at 10? 8 M. Cell proliferation and expression of specific osteoblast phenotype markers were analyzed.Key findingsMTT assay revealed that Ferutinin, at concentrations of 10? 8 and 10? 9 M, enhanced proliferation of both AFSCs and DPSCs after 72 h of exposure. Moreover, in both stem cell populations, Ferutinin treatment induced greater expression of the osteoblast phenotype markers osteocalcin (OCN), osteopontin (OPN), collagen I, RUNX-2 and osterix (OSX), increased calcium deposition and osteocalcin secretion in the culture medium compared to controls. These effects were more pronounced after 14 days of culture in both populations.SignificanceThe enhancing capabilities on proliferation and osteoblastic differentiation displayed by the phytoestrogen Ferutinin make this compound an interesting candidate to promote bone formation in vivo. 相似文献