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Yellow leaf mutants are useful genetic variants to explore the mechanism of chloroplast development. In this study, we developed and characterized a new rice (Orzya sativa L.) yellow leaf mutant, ygl54, with ethylmethane sulfonate (EMS) treatment on Zhenong 34, which exhibited leaf yellowing at early stage. By map-based cloning, OsYGL54 was located on long arm of chromosome 11 with a physical distance of 26 kb, and the substitution from G to A at the first exon of LOC_Os11g36440 was identified. Silent mutation in subsequent codon of ATG, disturbed the translation initiation, which caused lower expression level of OsYGL54 across the tissues. The histological analysis revealed that the chloroplast of mesophyll cells in ygl54 was disrupted with reduction in size of starch granules and higher number of plastoglobuli, which resulted in decreased chlorophyll contents, lower photosynthetic parameter, and lower expression level of genes associated with pigment metabolism and photosynthesis. The disruption in chloroplast caused higher accumulation of H2O2 and MDA contents. In conclusion, our results revealed the importance of sequence of second codon suggests that OsYGL54 was possibly involved in pigment metabolism and valuable for further study to explore the mechanism of chloroplast development. [ABSTRACT FROM AUTHOR]

Introduction: Prostate cancer cells can switch from an androgen-dependent state to an androgen-independent state after a continuous androgen ablation therapy. However, the molecular mechanisms underlying this switch are still unclear. Therefore, we explored the change in androgen receptor (AR)-related gene expression during this transition in a novel cell model. Material and methods: Prostate cancer cells were continuously treated with competitive androgen receptor inhibitor hydroxyflutamide for 1.5 years, which yielded an flutamide-insensitive LNCaP subline, LNCaP-flu, as confirmed by MTT assays, flow cytometry, and electron microscopy. We analyzed the differences in gene expression in LNCaP-flu cells and LNCaP cells using gene chips and follow-up RT-PCR. Results: Over 2,428 genes were differentially expressed between these cell lines: 1,194 were down-regulated and 1,234 were up-regulated. Three genes in particular were considered related to the androgen-dependent transition: NCOR1, TIF2 (NCOA2), and ARA70 (NCOA4). There were no apparent changes in expression of the androgen receptor or prostate-specific antigen. Conclusion: ARs and associated coregulators play a central role in the flutamide-insensitive transition of prostate cancer cells. Although AR expression does not change during this transition, the change in AR coregulators may be a critical factor in the development of antiandrogen insensitivity [ABSTRACT FROM AUTHOR]

The evolution of entanglement in a one-dimensional Ising chain with both two-body and three-body interactions, under two types of initial states, is numerically simulated. We analyse three problems concerning the dynamics of pairwise entanglement: (i) the possibility of generating large entanglement from an initial separable state by the use of a selective irradiation scheme; (ii) the effect of three-body interaction on the generation of entanglement from an initial separable state; (iii) the effect of three-body interaction on the decay of the entanglement from a state with only (m,n)-pair maximal entangled, and the rest in product form. It is shown that a large pairwise concurrence Cmn can be obtained when the resonant, transverse radio-frequency fields are selectively switched on from the mth to nth spins. Three-body interaction will decrease the oscillation amplitude of the nearest neighbour concurrence, while the oscillation amplitude of remote pairwise concurrence will be greatly increased with the consideration of three-body interactions. For an initial (m,n)-pair maximal entangled state, a slow decay of the pairwise concurrence Cmn is found with the introduction of three-body interactions. [ABSTRACT FROM AUTHOR]

Mineral nutrition of potassium (K), calcium (Ca), sodium (Na), magnesium (Mg), iron (Fe), zinc (Zn), copper (Cu) and manganese (Mn) are important for human health. The method of inductively coupled plasma mass spectrometry (ICP-MS) was employed to determinate the contents of K, Ca, Na, Mg, Fe, Zn, Cu and Mn in milled rice ( Oryza sativa L.) of 274 rice genotypes. The results showed that the visible difference could be found for the contents of eight elements in milled rice among rice genotypes studied. It existed the possibility to select the genotype(s) with abundant of mineral nutrient from the genetic resource. Meanwhile, the contents of mineral elements in brown rice were significantly higher than those in milled rice. The averages of K, Mn and Cu contents of indica rice were significantly lower than those of japonica rice, while no significant difference was found for other five element contents between indica and japonica rice genotypes. The average contents of Na and Cu in non-glutinous rice genotypes were higher than those in glutinous ones, whereas the averages of K and Mn contents in non-glutinous rice genotypes were lower in present experiment. Additionally, the K, Ca and Mg contents of milled rice from white brown rice were significantly higher than those from red brown rice, and Ca content of milled rice from white brown rice was also visibly higher than that from black brown rice. For microelements, significant difference was observed for Zn content between milled rice from red and white brown rice, or between milled rice from red and black brown rice. Some genotypes with abundant mineral nutrient in milled rice had been selected and could be used in rice nutrient breeding. [ABSTRACT FROM AUTHOR]

Investigations to identify quantitative trait loci (QTLs) governing cooking quality traits including amylose content, gel consistency and gelatinization temperature (expressed by the alkali spread value) were conducted using a set of 241 RIL populations derived from an elite hybrid cross of “Zhenshan 97” × “Minghui 63” and their reciprocal backcrosses BC1F1 and BC2F1 populations in two environments. QTLs and QTL × environment interactions were analyzed by using the genetic model with endosperm and maternal effects and environmental interaction effects on quantitative traits of seed in cereal crops. The results suggested that a total of seven QTLs were associated with cooking quality of rice, which were subsequently mapped to chromosomes 1, 4 and 6. Six of these QTLs were also found to have environmental interaction effects. [ABSTRACT FROM AUTHOR]

The article provides information on a study on embryo, cytoplasmic and maternal correlations for quality traits of rapeseed across environments. It is said that fatty acid component content and the nutrient quality of rapeseed oil are closely related. One of the most important aims in rapeseed breeding is said to be high oil content.

The selection of an appropriate sampling strategy and a clustering method is important in the construction of core collections based on predicted genotypic values in order to retain the greatest degree of genetic diversity of the initial collection. In this study, methods of developing rice core collections were evaluated based on the predicted genotypic values for 992 rice varieties with 13 quantitative traits. The genotypic values of the traits were predicted by the adjusted unbiased prediction (AUP) method. Based on the predicted genotypic values, Mahalanobis distances were calculated and employed to measure the genetic similarities among the rice varieties. Six hierarchical clustering methods, including the single linkage, median linkage, centroid, unweighted pair-group average, weighted pair-group average and flexible-beta methods, were combined with random, preferred and deviation sampling to develop 18 core collections of rice germplasm. The results show that the deviation sampling strategy in combination with the unweighted pair-group average method of hierarchical clustering retains the greatest degree of genetic diversities of the initial collection. The core collections sampled using predicted genotypic values had more genetic diversity than those based on phenotypic values. [ABSTRACT FROM AUTHOR]

Genetic effects and genotype×environment (GE) interaction effects on the cooking quality traits of indica rice ( Oryza sativa L.) were analyzed based on a genetic model for quantitative traits of triploid endosperm in cereal crops. Nine cytoplasmic male-sterile lines as females and 5 restoring lines as males were used in an incomplete diallel cross over 2 years. The cooking quality traits studied were observed to be mainly controlled by genetic effects, but GE interaction effects, especially for amylose content (AC) and alkali spreading score (ASS), were also indicated. Among the genetic effects, seed direct effects and maternal effects were the main components of AC and ASS, respectively; cytoplasmic effects were the main components of gel consistency (GC). Among the GE interaction effects, AC and ASS were mainly affected by maternal interaction effects and GC by direct interaction effects. Additive effects and/or additive interaction effects were the main factors controlling the performance of rice cooking quality traits except for GC which was affected by dominant interaction effects. For AC and GC, there were seed heterosis and/or maternal heterosis. The predicated genetic effects indicated that four parents were better than the others in improving the rice cooking quality traits of the progenies. It was shown that genetic heterosis and GE interaction heterosis were important, especially for amylose content trait in early season indica rice. [ABSTRACT FROM AUTHOR]