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Abstract We develop PIRCh-seq, a method which enables a comprehensive survey of chromatin-associated RNAs in a histone modification-specific manner. We identify hundreds of chromatin-associated RNAs in several cell types with substantially less contamination by nascent transcripts. Non-coding RNAs are found enriched on chromatin and are classified into functional groups based on the patterns of their association with specific histone modifications. We find single-stranded RNA bases are more chromatin-associated, and we discover hundreds of allele-specific RNA-chromatin interactions. These results provide a unique resource to globally study the functions of chromatin-associated lncRNAs and elucidate the basic mechanisms of chromatin-RNA interactions.

Doxorubicin (Adriamycin, ADM) is an antimitotic drug used in the treatment of a wide range of malignant tumors, including acute leukemia, lymphoma, osteosarcoma, breast cancer, and lung cancer. Multidrug resistance-associated proteins (MRPs) are members of a superfamily of ATP-binding cassette (ABC) transporters, which can transport various molecules across extra- and intra-cellular membranes. The aim of this study was to investigate whether there was a correlation between MRP4 and primary ADM resistance in osteosarcoma cells. In this paper, we chose the human osteosarcoma cell line MG63, ADM resistant cell line MG63/DOX, and the patient's primary cell GSF-0686. We checked the ADM sensitivity and cytotoxicity of all the three cells by cell proliferation assay. The intracellular drug concentrations were measured by using LC-MS/MS. We also examined MRP4 gene expression by RT-PCR and Western Blot. We found that the intracellular ADM concentration of the parent osteosarcoma cell line MG63 was higher than the ADM resistant osteosarcoma MG63/DOX cell line or the GSF-0686 cell after ADM treatment (P < 0.05). In addition, MRP4 mRNA and protein levels in ADM resistant osteosarcoma cells were higher than in MG63 cell (P < 0.05). Taking together, this work suggests that overexpression of MRP4 may confer ADM resistance in osteosarcoma cells. [ABSTRACT FROM AUTHOR]

Based on daily, monthly, seasonal and annual precipitation, monthly duration and flood-affected area data from 1954 to 2007, we examined the absolute and relative change trends of rainfall and their effects on hazard intensity in Wenzhou city, China. The long-term trend of precipitation was studied by linear regression, moving average, cumulative anomaly and Z index methods, respectively. Our results show that there was no significant downward trend of annual precipitation. In contrast, there was significant decrease in autumn, July, mid-January and early June and significant increase in early January and late May, especially in late June. During 1954 and 2007, although significant fluctuation existed in the absolute value of precipitation, the relative changes of wet and dry were not significant compared with the average. The 10-year decrease in precipitation was 23.37 mm in autumn, 14.85 mm in July, 0.33 mm in mid-January and 6.87 mm in early June; while the 10-year increase was 0.35 mm in early January, 3.05 mm in late May and 8.57 mm in late June, respectively. Moreover, we found that 1964, 1966, 1977 and 1995 were the transition periods when the rainfall Z index was at peaks, the flood intensity was high, and the drought intensity was relatively low. On the other hand, 1958, 1968, 1971, 1980, 1989 and 1992 were the periods when the rainfall Z index was at valleys, the flood intensity was low, and the drought intensity was relatively high. Taken together, we demonstrated the obvious effects of precipitation changes on flood and drought intensities. [ABSTRACT FROM AUTHOR]

Two sets of LSGs were identified using BLAST: Caenorhabditis elegans species-specific genes (SSGs, 1423), and Caenorhabditis genus-specific genes (GSGs, 4539). The data contained in this article show SSGs and GSGs have significant differences in evolution and that most of them were formed by gene duplication and integration of transposable elements (TEs). Subsequent observation of temporal expression and protein function presents that many SSGs and GSGs are expressed and that genes involved with sex determination, specific stress, immune response, and morphogenesis are most represented. The data are related to research article “Genome-wide identification of lineage-specific genes within Caenorhabditis elegans” in Journal of Genomics [1].

The laminar burning velocity of syngas/air premixed flames was studied by Bunsen burner and OH-PLIF system. The mole fractions of nitrogen in syngas change from 0 to 50% and the equivalence ratios vary from 0.6 to 1.2 were both considered to investigate those effects on the flame speed. A new method called slope averaging method was proposed to calculate the burning velocity and two classical methods were employed to verify its accuracy. A premixed code with GRI 3.0 mechanism was adopted to predict the burning velocity as well as to expose the dominant reactions on the formation of OH and H radicals. Results show that the slope averaging method represents the equal accuracy as the surface area method and is superior to the cone angle method. In addition, the increase of N2 fractions decreases the flame speed, and the effects of N2 dilution turn weak at fuel-lean conditions. Furthermore, the dominant reactions on the formation and consumption of OH and H radicals are inhibited as XN2 increases.

Triploid plants are usually highly aborted owing to unbalanced meiotic chromosome segregation, but limited viable gametes can participate in the transition to different ploidy levels. In this study, numerous meiotic abnormalities were found with high frequency in an intersectional allotriploid poplar (Populus alba × P. berolinensis 'Yinzhong'), including univalents, precocious chromosome migration, lagging chromosomes, chromosome bridges, micronuclei, and precocious cytokinesis, indicating high genetic imbalance in this allotriploid. Some micronuclei trigger mini-spindle formation in metaphase II and participate in cytokinesis to form polyads with microcytes. Unbalanced chromosome segregation and chromosome elimination resulted in the formation of microspores with aneuploid chromosome sets. Fusion of sister nuclei occurs in microsporocytes with precocious cytokinesis, which could form second meiotic division restitution (SDR)-type gametes. However, SDR-type gametes likely contain incomplete chromosome sets due to unbalanced segregation of homologous chromosomes during the first meiotic division in triploids. Misorientation of spindles during the second meiotic division, such as fused and tripolar spindles with low frequency, could result in the formation of first meiotic division restitution (FDR)-type unreduced gametes, which most likely contain three complete chromosome sets. Although 'Yinzhong' yields 88.7% stainable pollen grains with wide diameter variation from 23.9 to 61.3 μm, the pollen viability is poor (2.78% ± 0.38). A cross of 'Yinzhong' pollen with a diploid female clone produced progeny with extensive segregation of ploidy levels, including 29 diploids, 18 triploids, 4 tetraploids, and 48 aneuploids, suggesting the formation of viable aneuploidy and unreduced pollen in 'Yinzhong'. Individuals with different chromosome compositions are potential to analyze chromosomal function and to integrate the chromosomal dosage variation into breeding programs of Populus.