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排序方式: 共有626条查询结果,搜索用时 49 毫秒
581.
Involvement of a glucosinolate (sinigrin) in the regulation of water transport in Brassica oleracea grown under salt stress 总被引:2,自引:0,他引:2
Maria del Carmen Martínez‐Ballesta Beatriz Muries Diego Ángel Moreno Raúl Dominguez‐Perles Cristina García‐Viguera Micaela Carvajal 《Physiologia plantarum》2014,150(2):145-160
Members of the Brassicaceae are known for their contents of nutrients and health‐promoting phytochemicals, including glucosinolates. The concentrations of these chemopreventive compounds (glucosinolate‐degradation products, the bioactive isothiocyanates) may be modified under salinity. In this work, the effect of the aliphatic glucosinolate sinigrin (2‐propenyl‐glucosinolate) on plant water balance, involving aquaporins, was explored under salt stress. For this purpose, water uptake and its transport through the plasma membrane were determined in plants after NaCl addition, when sinigrin was also supplied. We found higher hydraulic conductance (L0) and water permeability (Pf) and increased abundance of PIP2 aquaporins after the direct administration of sinigrin, showing the ability of the roots to promote cellular water transport across the plasma membrane in spite of the stress conditions imposed. The higher content of the allyl‐isothiocyanate and the absence of sinigrin in the plant tissues suggest that the isothiocyanate is related to water balance; in fact, a direct effect of this nitro‐sulphate compound on water uptake is proposed. This work provides the first evidence that the addition of a glucosinolate can regulate aquaporins and water transport: this effect and the mechanism(s) involved merit further investigation. 相似文献
582.
Jayaraman Selvaraj Shazia Fathima JH Venkatacalam Sivabalan Umapathy Vidhya Rekha Rajagopal Ponnulakshmi Veeraraghavan Vishnupriya Malathi Kullappan Radhika Nalinakumari Sreekandan Surapaneni Krishna Mohan Periyasamy Vijayalakshmi 《Bioinformation》2021,17(1):200
Cornulin (CRNN) is linked with tumour progression. Therefore, it is of interest to document data on the molecular modeling of cornulin (CRNN) for docking with phytocompounds (Pyrazinamide, Anisotine, Vasicinone, Vasicoline) from Justicia adhatoda L. Thus, we document the optimal binding features of these compounds with the cornulin model for further consideration. 相似文献
583.
Jayaraman Selvaraj Umapathy Vidhya Rekha Shazia Fathima JH Venkatacalam Sivabalan Rajagopal Ponnulakshmi Veeraraghavan Vishnupriya Malathi Kullappan Radhika nalinakumari Sreekandan Surapaneni Krishna Mohan 《Bioinformation》2021,17(1):167
It is of interest to document the moelcular docking analysis of SARS-CoV-2 linked RNA dependent RNA polymerase (RdRp) with compounds from Plectranthus amboinicus. Hence, we report the binding features of rutin, Luteolin, Salvianolic acid A, Rosmarinic acid and p-Coumaric acid with the target protein SARS-CoV-2 linked RNA dependent RNA polymerase (RdRp) for further consideration. 相似文献
584.
Garcia-Garcia RM Dominguez V Gonzalez-Bulnes A Veiga-Lopez A Cocero MJ 《Zygote (Cambridge, England)》2006,14(3):181-187
This study evaluated the final output and quality of in vitro produced blastocysts derived from in vivo recovered sheep embryos cultured at various early developmental stages to blastocyst. A total of 270 embryos were recovered from the oviduct, at different days of the early luteal phase, and were classified into three different developmental stages: 2- to 4-cell (n = 93); 5- to 8-cell (n = 92) and 9- to 12-cell (n = 85). The effect of culture conditions was studied, at the same time, by randomly allocating the embryos to one of four groups: three groups of culture with fresh oviduct monolayers (2, 4 and 5 days old) and a fourth group with 2-day monolayers derived from frozen-thawed oviduct cells. Two control groups were established: first, embryos cultured in semi-defined medium (n = 29) and, second, blastocysts obtained in vivo and cryopreserved (n = 43). Influence on blastocyst yield of embryo developmental stage at the start of culture was statistically significant (p < 0.001). Two- to four-cell embryos showed a significantly lower developmental rate (67.7%) than the 5- to 8-cell (83.6%; p < 0.001) and 9- to 12-cell groups (90.5%; p < 0.0001) and lower quality in terms of blastocyst cryotolerance (56.0 vs. 83.7%; p < 0.005). There were no detected effects relating to the age or handling of the monolayer on the embryo developmental rate, but the day of blastocyst appearance was different between embryos cultured on monolayers derived from fresh or frozen-thawed cells (p < 0.0001); the main influence was on the group of 9- to 12-cell embryos (p < 0.0001). Current results confirm the temporal sensitivities of sheep embryos to in vitro culture, regardless of the culture conditions. 相似文献
585.
Borrego-Diaz E Kerff F Lee SH Ferron F Li Y Dominguez R 《Journal of structural biology》2006,155(2):230-238
Alpha-actinin belongs to the spectrin family of actin crosslinking and bundling proteins that function as key regulators of cell motility, morphology and adhesion. The actin-binding domain (ABD) of these proteins consists of two consecutive calponin homology (CH) domains. Electron microscopy studies on ABDs appear to support two competing actin-binding models, extended and compact, whereas the crystal structures typically display a compact conformation. We have determined the 1.7A resolution structure of the ABD of alpha-actinin 1, a ubiquitously expressed isoform. The structure displays the classical compact conformation. We evaluated the two binding models by surface conservation analysis. The results show a conserved surface that spans both domains and corresponds to two previously identified actin-binding sites (ABS2 and ABS3). A third, and probably less important site, ABS1, is mostly buried in the compact conformation. However, a thorough examination of existing structures suggests a weak and semi-polar binding interface between the two CHs, leaving open the possibility of domain reorientation or opening. Our results are consistent with a two-step binding mechanism in which the ABD interacts first in the compact form observed in the structures, and then transitions toward a higher affinity state, possibly through minor rearrangement of the domains. 相似文献
586.
Elena Gutierrez Piedad Gallego Angel Alonso Antonio Blazquez Luisa Martin Javier Fernandez Leticia Dominguez Cristina Rioja Hilario Guerra Nieves Villalobos 《In vitro cellular & developmental biology. Plant》2010,46(3):257-264
Nitrogen (N) metabolism during embryogenesis may be fundamental in the embryogenic response. We used different explants of
Medicago arborea L. subsp. arborea seedlings: cotyledons, petioles and leaves, which form calluses with different embryogenic responses. The endogenous contents
of total nitrogen, nitrate, nitrite and ammonia and nitrate reductase activity were determined in embryogenic and non-embryogenic
calluses induced from the different explants. The endogenous total N content decreased in the calluses as the culture time
progressed, this decrease being more pronounced in the more embryogenic calluses obtained from petioles with the H8 and F0
media. Inorganic N decreased during embryogenesis, coinciding with an increase in organic N. Thus, N metabolism somehow seems
to be essential in embryogenesis. The N detected in calluses, at the start of culture, was mainly metabolised to nitrite.
This metabolism was very pronounced; especially in embryogenic calluses obtained from cotyledons and petioles. That is, the
metabolism of N seemed to be more marked in the calluses in which embryogenesis was greater. The nitrite content decreased
in all the calluses, the contents being lower, especially in the last months of culture, in the more embryogenic calluses
obtained from petioles. In many calluses, ammonia levels did not follow any general pattern. Neither was it possible to detect
changes in ammonia levels between the embryogenic and non-embryogenic calluses. Regarding nitrate reductase activity, no clear
differences between embryogenic and non-embryogenic calluses were found. 相似文献
587.
588.
We recently reported that bile salts play a role in the regulation of mucin
secretion by cultured dog gallbladder epithelial cells. In this study we
have examined whether bile salts also influence mucin secretion by the
human epithelial colon cell line LS174T. Solutions of bile salts were
applied to monolayers of LS174T cells. Mucin secretion was quantified by
measuring the secretion of [3H]GlcNAc labeled glycoproteins. Both
unconjugated bile salts as well as taurine conjugated bile salts stimulated
mucin secretion by the colon cells in a dose-dependent fashion. Hydrophobic
bile salts were more potent stimulators than hydrophilic bile salts. Free
(unconjugated) bile salts were more stimulatory compared with their taurine
conjugated counterparts. Stimulation of mucin secretion by LS174T cells was
found to occur at much lower bile salt concentrations than in the
experiments with the dog gallbladder epithelial cells. The protein kinase C
activators PMA and PDB had no stimulatory effect on mucin secretion. We
conclude that mucin secretion by the human colon epithelial cell line
LS174T is regulated by bile salts. We suggest that regulation of mucin
secretion by bile salts might be a common mechanism, by which different
epithelia protect themselves against the detergent action of bile salts, to
which they are exposed throughout the gastrointestinal tract.
相似文献
589.
590.
Ponnulakshmi Rajagopal Selvaraj Jayaraman Shazia Fathima JH Saravanan Radhakrishnan Patil Ashlesh Laxman Vijaya Prakash Krishnan Muthaiah Satyendra Chandra Tripathi TS Gugapriya Aaditya Madhusudan Tarnekar Gayatri Girish Muthiyan Vishwajit Ravindra Deshmukh Bharat Ramrao Sontakke Kirubhanand Chandrashekar 《Bioinformation》2021,17(11):928