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1.
The opportunity for intensity of selection is studied in two backward caste groups with different occupations, namely Yadava (pastoral) and Vadabalija (fishing) of Bheemunipatnam Taluk of Visakhapatnam District, Andhra Pradesh. The amount of selection intensity is found to be higher in Vadabalija (0.8583) than Yadava (0.5827). The contribution of mortality to the total index of selection is greater in Vadabalija (0.6095) than in Yadava (0.3326). When consanguineity is considered, the fertility components of selection intensity (0.1885) are lower in the consanguineous group of Yadava than in the nonconsanguineous group (0.2845), whereas in Vadabalija they are higher in the consanguineous group (0.5261) than in the nonconsanguineous group (0.2223). 相似文献
2.
Epicotyl, petiole, and cotyledon explants derived from 14-d-old seedlings of Albizia odoratissima were cultured on Murashige and Skoog (MS) basal medium supplemented with different concentrations of either 6-benzylaminopurine
(BAP) solely or in combination with 0.5 μM naphthalene-3-acetic acid (NAA). The percentage of shoot regeneration and the number
of shoots regenerated varied significantly depending on the type of explants used, the concentration of plant growth regulators,
and the orientation of explants on the culture medium. The best response in terms of the percentage of shoot regeneration
was obtained from epicotyls cultured horizontally on MS medium supplemented with 5 μM BAP, whereas the highest number of shoots
per responding explant was recorded on medium containing 2.5 μM BAP and 0.5 μM NAA. Successful rooting was achieved by placing
the microshoots onto MS medium containing 25 μM indole-3-butyric acid (IBA) for 24 h first, then transferring to the same
medium without IBA. Of the various substrates tested, vermiculite was the best for plant acclimatization, as 75% of the plants
survived and became established. 相似文献
3.
The stem-loop in the 5' untranslated region (UTR) of collagen α1(I) and α2(I) mRNAs (5'SL) is the key element regulating their stability and translation. Stabilization of collagen mRNAs is the predominant mechanism for high collagen expression in fibrosis. LARP6 binds the 5'SL of α1(I) and α2(I) mRNAs with high affinity. Here, we report that vimentin filaments associate with collagen mRNAs in a 5'SL- and LARP6-dependent manner and stabilize collagen mRNAs. LARP6 interacts with vimentin filaments through its La domain and colocalizes with the filaments in vivo. Knockdown of LARP6 by small interfering RNA (siRNA) or mutation of the 5'SL abrogates the interaction of collagen mRNAs with vimentin filaments. Vimentin knockout fibroblasts produce reduced amounts of type I collagen due to decreased stability of collagen α1(I) and α2(I) mRNAs. Disruption of vimentin filaments using a drug or by expression of dominant-negative desmin reduces type I collagen expression, primarily due to decreased stability of collagen mRNAs. RNA fluorescence in situ hybridization (FISH) experiments show that collagen α1(I) and α2(I) mRNAs are associated with vimentin filaments in vivo. Thus, vimentin filaments may play a role in the development of tissue fibrosis by stabilizing collagen mRNAs. This finding will serve as a rationale for targeting vimentin in the development of novel antifibrotic therapies. 相似文献
4.
Bhumika Ray Shweta Agarwal Neelam Lohani Moganty R. Rajeswari 《Journal of biomolecular structure & dynamics》2016,34(11):2518-2535
Certain plant-derived alkaloids and flavonoids have shown propitious cytotoxic acitvity against different types of cancer, having deoxyribose nucleic acid (DNA) as their main cellular target. Flavopiridol, a semi-synthetic derivative of rohitukine (a natural compound isolated from Dysoxylum binectariferum plant), has attained much attention owing to its anticancer potential against various haematological malignancies and solid tumours. This work focuses on investigating interaction between flavopiridol and DNA at molecular level in order to decipher its underlying mechanism of action, which is not well understood. To define direct influence of flavopiridol on the structural, conformational and thermodynamic aspects of DNA, various spectroscopic and calorimetric techniques have been used. ATR-FTIR and SERS spectral outcomes indicate a novel insight into groove-directed-intercalation of flavopiridol into DNA via direct binding with nitrogenous bases guanine (C6=O6) and thymine (C2=O2) in DNA groove together with slight external binding to its sugar–phosphate backbone. Circular dichroism spectral analysis of flavopiridol–DNA complexes suggests perturbation in native B-conformation of DNA and its transition into C-form, which may be localized up to a few base pairs of DNA. UV–visible spectroscopic results illustrate dual binding mode of flavopiridol when interacts with DNA having association constant, Ka = 1.18 × 104 M?1. This suggests moderate type of interaction between flavopiridol and DNA. Further, UV melting analysis also supports spectroscopic outcomes. Thermodynamically, flavopiridol–DNA complexation is an enthalpy-driven exothermic process. These conclusions drawn from this study could be helpful in unveiling mechanism of cytoxicity induced by flavopiridol that can be further applied in the development of flavonoid-based new chemotherapeutics with more specificity and better efficacy. 相似文献
5.
The quantity and patterns of net mineralization of soil nitrogen (N) were studied in Vertisols under different cropping systems in the semi-arid tropical areas. Eight cropping systems were selected; three contained pigeonpea (PP), one contained PP and cowpea (COP), and two contained chickpea (CP) as legume component crops, one included sequence cropping with nonlegumes during the rainy and postrainy seasons, and one system was kept fallow (F) during the rainy season and sown to sorghum (S) during the postrainy season. Cropping systems with PP as a component crop increased mineralizable N(N
o
) content two-fold in the soil compared with fallow + sorghum (F+S)–F+S system. The N mineralization rate constant (k) was not significantly affected by previous cropping history of the soil; however, a numerically higher rate constant was observed in the COP/PP intercrop, followed by sequential S+safflower (SF) system as compared to the other soils. Mineral N accumulation curves for six soils were more accurately described by the exponential model than the linear model. The active N fraction (N
o
/Ntot %) varied between 8 and 16% for different systems and a direct relationship was observed between N
o
/Ntot and total N for the soils under diverse cropping systems.ICRISAT JA (1638) 相似文献
6.
Hypocotyls of Albizia odoratissima cultured on shoot induction medium (MS medium with 7.5 μM BAP and 0.5 μM NAA) showed adventitious shoot organogenesis under
light with 16 h photoperiod. Similar cultures under total darkness produced non-morphogenic calli. The changes in the specific
peroxidase and catalase activity, total protein content and acidic isoperoxidase pattern were compared between the culture
showing shoot organogenesis and culture producing non-morphogenic calli. It was found that in vitro shoot bud differentiation
is accompanied by an increase of the specific activities of peroxidase and catalase in culture kept under light. In parallel
with the above changes the total protein content reached to the maximum level and also a new isoperoxidase (P10) expressed
on the 21st day in cultures kept under light. Conversely, culture producing non-morphogenic calli underwent a reverse change
in specific peroxidase activity. This change in antioxidant enzyme activities corresponds to the histological observation
of shoot bud differentiation in cultures kept under light. 相似文献
7.
8.
Rajeswari SR Jonnalagadda VS Jonnalagadda S 《Indian journal of biochemistry & biophysics》1999,36(3):137-142
The ATP-dependent phosphorylation of riboflavin to FMN by flavokinase is the key step in flavin biosynthesis. Flavokinase has been purified from a fungal source for the first time. The enzyme purified from a cell wall lacking mutant of Neurospora crassa, slime, is a monomer of M(r) 35.5 kDa with maximal activity at alkaline pH and high temperature (55 degrees C). The K(m) for both substrates is the lowest reported for flavokinase from any source so far (120 nM for riboflavin and 210 nM for MgATP2-). The enzyme exhibits preference for Mg2+ over Zn2+ as the essential activator and is also significantly activated by several cations. Activation by orthophosphate may be physiologically relevant for the intracellular regulation of flavokinase. 相似文献
9.
10.
V Viswanathan S Kumpatla V Aravindalochanan R Rajan C Chinnasamy R Srinivasan JM Selvam A Kapur 《PloS one》2012,7(7):e41367