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The use of aspirin is associated with a lower risk of many cancer types. However, there are few reports about cervical cancer. The proto-oncogene ErbB2 is overexpressed in cervical cancer, and considered as a therapeutic target. In the present study, we investigated whether aspirin had therapeutic value in cervical cancer and examined the effects of aspirin on the amplification and expression of ErbB2. To investigate the effects of aspirin on apoptosis and proliferation, we tested apoptosis by Hoechst 33258 staining and Annexin V-FITC/PI method; MTT assay and colony formation assay were used to detect proliferation. Induction of apoptosis and inhibition of proliferation were observed in HeLa cells incubated with aspirin. Western blot and immunocytochemical staining showed that aspirin induced a dose- and time-dependent reduction of ErbB2 expression that was due to proteosome-mediated degradation of this protein. To further investigate the underlying mechanism by which aspirin exerts its apoptosis effects, we studied the ErbB2 downstream cell survival signaling pathways and the expression of anti-apoptosis gene Bcl-2. We found that aspirin inhibited the activation of extracellular signal-regulated kinase (ERK) and AKT. The inhibition of Bcl-2 expression was also observed. These data reveal that aspirin significantly induces apoptosis and inhibits proliferation, which maybe via inhibiting ErbB2 downstream cell survival signaling pathways. Taken together, our article describes a novel mechanism of action for anti-tumor activity of aspirin and implicates aspirin as a novel agent for cervical cancer.

Obtaining genetic variation information from indica rice hybrid parents and identification of loci associated with heterosis are important for hybrid rice breeding. Here, we resequence 1,143 indica accessions mostly selected from the parents of superior hybrid rice cultivars of China, identify genetic variations, and perform kinship analysis. We find different hybrid rice crossing patterns between 3- and 2-line superior hybrid lines. By calculating frequencies of parental variation differences (FPVDs), a more direct approach for studying rice heterosis, we identify loci that are linked to heterosis, which include 98 in superior 3-line hybrids and 36 in superior 2-line hybrids. As a proof of concept, we find two accessions harboring a deletion in OsNramp5, a previously reported gene functioning in cadmium absorption, which can be used to mitigate rice grain cadmium levels through hybrid breeding. Resource of indica rice genetic variation reported in this study will be valuable to geneticists and breeders.

BackgroundWith an increasing world population and a gradual decline in the amount of arable land, food security remains a global challenge. Continued increases in rice yield will be required to break through the barriers to grain output. In order to transition from hybrid rice to super-hybrid rice, breeding demands cannot be addressed through traditional heterosis. Therefore, it is necessary to incorporate high yield loci from other rice genetic groups and to scientifically utilize intersubspecific heterosis in breeding lines. In this study, 781 lines from a segregating F2 population constructed by crossing the indica variety, “Giant Spike Rice” R1128 as trait donor with the japonica cultivar ‘Nipponbare’, were re-sequenced using high-throughout multiplexed shotgun genotyping (MSG) technology. In combination with high-density single nucleotide polymorphisms, quantitative trait locus (QTL) mapping and genetic effect analysis were performed for five yield factors (spikelet number per panicle, primary branches per panicle, secondary branches per panicle, plant height, and panicle length) to explore the genetic mechanisms underlying the formation of the giant panicle of R1128. Also, they were preformed to locate new high-yielding rice genetic intervals, providing data for super-high-yielding rice breeding.ResultsQTL mapping and genetic effect analysis for five yield factors in the population gave the following results: 49 QTLs for the five yield factors were distributed on 11 of 12 chromosomes. The super-hybrid line R1128 carries multiple major genes for good traits, including Sd1 for plant height, Hd1 and Ehd1 for heading date, Gn1a for spikelet number and IPA1 for ideal plant shape. These genes accounted for 44.3%, 21.9%, 6.2%, 12.9% and 10.6% of the phenotypic variation in the individual traits. Six novel QTLs, qph1-2, qph9-1, qpl12-1, qgn3-1, qgn11-1 and qsbn11-1 are reported here for the first time.ConclusionsHigh-throughout sequencing technology makes it convenient to study rice genomics and makes the QTL/gene mapping direct, efficient, and more reliable. The genetic regions discovered in this study will be valuable for breeding in rice varieties because of the diverse genetic backgrounds of the rice.Electronic supplementary materialThe online version of this article (doi:10.1186/1939-8433-6-21) contains supplementary material, which is available to authorized users.

The gelatinization temperature (GT) of endosperm starch influences rice eating and the cooking quality (ECQ). ALK encoding soluble starch synthase IIa (SSIIa) is the major gene determining grain GT in rice. Herein, we identified a spontaneous ALK mutant named ALK d , which resulted from a G/T single-nucleotide polymorphism (SNP) in exon 1 of the ALK c allele from the high-GT indica rice cultivar. Compared with grains from the ALK c near-isogenic line (NIL), NIL(ALK d ) grains exhibited a high GT (2.3 °C) and improved retrogradation properties. The NIL(ALK d ) grain starch contained an increased proportion of amylopectin intermediate chains (DP 13−24) at the expense of short chains (DP < 12), resulting in enhancements in both the crystallinity and the lamellar peak intensity compared with low-GT rice grains. Moreover, both NIL(ALK d ) and NIL(ALK c ) grains also featured a significantly lower apparent amylose content (AAC), harder gel consistency (GC), higher pasting curve, and poorer taste values in comparison to Nip(ALK a ) grains. Taken together, this work provides novel insights underlying the allelic variation of the ALK gene in rice.

To estimate genetic parameters of growth traits in Japanese flounder Paralichthys olivaceus, full-sib and half-sib families were produced in three consecutive years at the Beidaihe Central Experiment Station in China. Each year 8-28 families were produced. The body weight, body length and body depth at 180, 240, and 360 days of age were measured for 5,224 individuals. Four animal models were used to examine the phenotypic variation of growth traits and were compared using the likelihood ratio test. The results showed that estimates for additive genetic effect heritabilities varied greatly depending on the model, trait and age. The maternal effect had a significant impact on phenotypic variation only for body depth at 180 days of age, which explained 49% of the phenotypic variance. The ratio of full-sib effect to phenotypic variation ranged from 0.09 to 0.22. Growth traits all exhibited low heritability (0.13-0.39), indicating that there is the potential for family selection breeding for these traits in Japanese flounder. Using the full model with the fixed, full-sib family, additive and maternal genetic effects, genetic correlations among the three traits for fish of the same age were estimated to be more than 0.80. Generally, the genetic correlations gradually increased as age increased.

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Chromosome segment duplications are integral in genome evolution by providing a source for the origin of new genes. In the rice genome, besides an ancient polyploidy event known in the rice common ancestor, it had been identified that there was a special segmental duplication involving chromosomes 11 and 12, but the biological role of this duplication remains unknown. In this study, by using a set of chromosome segment substitution lines (CSSLs) and near isogenic lines (NILs) derived from the indica cultivar 9311 and japonica cultivar Nipponbare, a major QTL (qS12) resulting in hybrid male sterility was mapped within ~400 kb region adjacent to the special duplicated segment on the short arm of chromosome 12. Compared to the japonica cultivar Nipponbare, the two sides of the qS12 candidate region were inverted in the indica cultivar 9311. Among 47 of the 111 rice genotypes evaluated by molecular markers, the inverted sides were detected, and found completely homologous to indica cultivar 9311. These results suggested that the two inverted sides protect the sequence in the qS12 regions from recombination. On the short-arm of chromosome 12, two QTLs S-e and S25, in addition to qS12, were previously detected as a distinct segregation distortion and pollen semi-sterility loci. We propose these three hybrid sterility loci are the same locus, and the duplicated segment on chromosome 12 may play a prominent role in diversification, i.e., sub-speciation of cultivated rice.