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291.
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293.
Phosphorylation of activation functions AF-1 and AF-2 of RAR alpha and RAR gamma is indispensable for differentiation of F9 cells upon retinoic acid and cAMP treatment. 总被引:2,自引:0,他引:2 下载免费PDF全文
R Taneja C Rochette-Egly J L Plassat L Penna M P Gaub P Chambon 《The EMBO journal》1997,16(21):6452-6465
The role of RAR alpha 1 and RAR gamma 2 AF-1 and AF-2 activation functions and of their phosphorylation was investigated during RA-induced primitive and parietal differentiation of F9 cells. We found that: (i) primitive endodermal differentiation requires RAR gamma 2, whereas parietal endodermal differentiation requires both RAR gamma 2 and RAR alpha 1, and in all cases AF-1 and AF-2 must synergize; (ii) primitive endodermal differentiation requires the proline-directed kinase site of RAR gamma 2-AF-1, whereas parietal endodermal differentiation additionally requires that of RAR alpha 1-AF-1; (iii) the cAMP-induced parietal endodermal differentiation also requires the protein kinase A site of RAR alpha-AF-2, but not that of RAR gamma; and (iv) the AF-1-AF-2 synergism and AF-1 phosphorylation site requirements for RA-responsive gene induction are promoter context-dependent. Thus, AF-1 and AF-2 of distinct RARs exert specific cellular and molecular functions in a cell-autonomous system mimicking physiological situations, and their phosphorylation by kinases belonging to two main signalling pathways is required to enable RARs to transduce the RA signal during F9 cell differentiation. 相似文献
294.
Sahoo Sripati Abhiram Jha Zenu Verulkar Satish B. Srivastava Ashish K. Suprasanna Penna 《Plant Cell, Tissue and Organ Culture》2019,137(1):187-192
Plant Cell, Tissue and Organ Culture (PCTOC) - The study provides high-throughput protocol for ploidy determination which may accelerate the production of double haploids in rice. Advancements in... 相似文献
295.
V. A. Bapat A. S. Nirale V. M. Kulkarni P. Suprasanna P. S. Rao 《Journal of plant biochemistry and biotechnology.》2001,10(1):79-81
Banana (Musa sp) plants regenerated from in vitro culture were employed to study varietal differences of 32P uptake. The results demonstrated that the selected varieties exhibited considerable variation for absorption, translocation and transport index of PO4 uptake. Use of tissue cultured derived plants can be efficiently utilised to analyse varietal differences in 32P uptake. 相似文献
296.
Giovanni La Penna Sara Furlan Lucia Banci 《Journal of biological inorganic chemistry》2007,12(2):180-193
Nuclear magnetic resonance experiments performed on yeast mitochondrial cytochrome c (Cytc), a paradigmatic electron transfer protein, reveal that the two oxidation states have similar structures, but different mobility:
despite the few structural differences compared with the reduced form, the oxidized form displays a larger unfolding propensity.
Molecular dynamics simulations performed on both NMR reduced and NMR oxidized forms show that the reduced form has a larger
solvent-accessible surface area (SASA). Starting from this observation, a molecular statistical approach was then applied
in order to correlate the molecular surface to molecular mobility. Simulations started from biased initial conditions corresponding
to different molecular sizes were combined with the maximal constrained entropy method. The NMR structure of oxidized Cytc is more suited to expose a smaller SASA than the NMR structure of the reduced form, but the accessible conformational landscape
at 300 K around the NMR oxidized structure is flatter than for the NMR reduced structure. Protein configurations of smaller
SASA and size display larger plasticity when they resemble the NMR oxidized structure, whereas they are more rigid when they
resemble the NMR reduced structure. Implications of the results for the protein properties during its functional process are
discussed.
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users. 相似文献
297.
Animals using sound communication employ different strategies to overcome interferences from biotic and abiotic sources. However, interactions among acoustically active species have been studied to a very limited extent. The evoked vocal responses of 20 male frogs Batrachyla taeniata from the temperate austral forest in Chile were tested with conspecific calls and with the calls of two sympatric species: B. antartandica and B. leptopus, broadcast at amplitudes of 73, 79, 85, 91 and 97 dB peak SPL. The subjects responded actively to the conspecific call, but only responded weakly to the call of B. leptopus at the highest intensity. The preferential responses to conspecific calls could contribute to the typical segregation in monospecific choruses observed in areas where these frogs breed in sympatry. 相似文献
298.
Mahendra Laxman Ahire Savaliram Goga Ghane Vinayak Haribhau Lokhande Penna Suprasanna Tukaram Dayaram Nikam 《In vitro cellular & developmental biology. Plant》2011,47(4):488-495
Uraria picta is extensively used in the Asian traditional systems of medicine. Overexploitation of the species for preparation of the
drug Dashmula has led to the plant becoming rare and endemic. In the present investigation, an efficient micropropagation
protocol has developed from leaf-derived callus of U. picta. Among the various concentrations of cytokinins (6-benzyladenine—BA; kinetin—Kin; and thidiazuron—TDZ) used, a significantly
higher number of shoots per culture (58.8 ± 0.8) was observed on Murashige and Skoog (MS) medium fortified with 4.44 μM BA.
The shoot regeneration frequency was sustained upon transfer to the same fresh medium at 4-wk intervals over a period of 2 yr.
The medium containing various concentrations of auxins (α-napthalene acetic acid (NAA) or indole-3-acetic acid (IAA)) showed
callus interspersed root formation; however, MS basal medium containing 3% sucrose revealed direct root induction from in vitro raised shoots. The acclimatized in vitro grown plants showed almost 98% survival upon transfer to soil in earthen pots and grown ex vitro. Randomly amplified polymorphic DNA analysis of 25 arbitrarily selected regenerants and mother plants revealed 100% uniformity
and true-to-type nature of the regenerants. Methanolic extracts of callus showed strong antibacterial activity against pathogenic
bacteria as compared to leaf and root extracts of in vitro raised plants and wild plants, suggesting the presence of higher concentrations of active chemical constituents (isoflavanoids)
in callus cultures of U. picta. 相似文献
299.
PPAR‐α agonist elicits metabolically active brown adipocytes and weight loss in diet‐induced obese mice 下载免费PDF全文
300.
Mario Penna Felipe N. Moreno-Gómez 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2014,200(3):171-181
The efficiency of acoustic communication depends on the power generated by the sound source, the attributes of the environment across which signals propagate, the environmental noise and the sensitivity of the intended receivers. Eupsophus emiliopugini, an anuran from the temperate austral forest communicates by means of an advertisement call of moderate intensity within the range for anurans. To estimate the range over which these frogs communicate effectively, we conducted measurements of call sound levels and of auditory thresholds to pure tones and to synthetic conspecific calls. The results show that E. emiliopugini produces advertisement calls of about 84 dB SPL at 0.25 m from the caller. The signals are affected by attenuation as they propagate, reaching average values of about 47 dB SPL at 8 m from the sound source. Midbrain multi-unit recordings show quite sensitive audiograms within the anuran range, with thresholds of about 44 dB SPL for synthetic imitations of conspecific calls, which would allow communication at distances beyond 8 m. This is an extended range as compared to E. calcaratus, a related syntopic species for which a previous study has shown to be restricted to active acoustic spaces shorter than 2 m. The comparison reveals divergent strategies for related taxa communicating amid the same environment. 相似文献