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In this study, we characterized the miR482 family in cotton using existing small RNA datasets and the recently released draft genome sequence of Gossypium raimondii, a diploid cotton species whose progenitor is the putative contributor of the Dt (representing the D genome of tetraploid) genome of the cultivated tetraploid cotton species G. hirsutum and G. barbadense. Of the three ghr-miR482 members reported in G. hirsutum, ghr-miR482a has no homolog in G. raimondii, ghr-miR482b and ghr-miR482c each has a single homolog in G. raimondii. Gra-miR482d has five homologous loci (gra-miR482d, f-i) in G. raimondii and also exists in G. hirsutum (ghr-miR482d). A variant, miR482.2 that is a homolog of miR2118 in other species, is produced from several GHR-MIR482 loci in G. hirsutum. Approximately 12% of the G. raimondii NBS-LRR genes were predicted targets of various members of the gra-miR482 family. Based on the rationale that the regulatory relationship between miR482 and NBS-LRR genes will be conserved in G. raimondii and G. hirsutum, we investigated this relationship using G. hirsutum miR482 and G. raimondii NBS-LRR genes, which are not currently available in G. hirsutum. Ghr-miR482/miR482.2-mediated cleavage was confirmed for three of the four NBS-LRR genes analysed. As in tomato, miR482-mediated cleavage of NBS-LRR genes triggered production of phased secondary small RNAs in cotton. In seedlings of the susceptible cultivar Sicot71 (G. hirsutum) infected with the fungal pathogen Verticillium dahliae, the expression levels of ghr-miR482b/miR482b.2, ghr-miR482c and ghr-miR482d.2 were down-regulated, and several NBS-LRR targets of ghr-miR482c and ghr-miR482d were up-regulated. These results imply that, like tomato plants infected with viruses or bacteria, cotton plants are able to induce expression of NBS-LRR defence genes by suppression of the miRNA-mediated gene silencing pathway upon fungal pathogen attack.

Validating model simulations of vegetation-climate feedback needs information not only on changes in past vegetation types as reconstructed by palynologists, but also on other proxies such as vegetation cover. We present here a quantitative regional vegetation cover reconstruction for North China during the Holocene. The reconstruction was based on 15 high-quality lake sediment profiles selected from 55 published sites in North China, along with their modern remote sensing vegetation index. We used the surface soil pollen percentage to build three pollen-vegetation cover transfer models, and used lake surface sediment pollen data to validate their accuracy. Our results showed that vegetation cover in North China increased slightly before its maximum at 6.5 cal ka BP and has since declined significantly. The vegetation decline since 6.5 cal ka BP has likely induced a regional albedo change and aerosol increase. Further comparison with paleoclimate and paleovegetation dynamics in South China reproduced the regional cooling effect of vegetation cover decline in North China modelled in previous work. Our discussion demonstrates that, instead of reconstructing vegetation type from a single site, reconstructing quantitative regional vegetation cover could offer a broader understanding of regional vegetation-climate feedback.

Interleukin (IL)-32 is a recently described pro-inflammatory cytokine that has been reported to be induced by bacteria treatment in culture cells. Little is known about IL-32 production by exogenous pathogens infection in human individuals.In this study, we found that IL-32 level was increased by 58.2% in the serum samples from a cohort of 108 patients infected by influenza A virus comparing to that of 115 healthy individuals. Another pro-inflammatory factor cyclooxygenase (COX)-2-associated prostaglandin E2 was also upregulated by 2.7-fold. Expression of IL-32 in influenza A virus infected A549 human lung epithelial cells was blocked by either selective COX-2 inhibitor NS398 or Aspirin, a known anti-inflammatory drug, indicating IL-32 was induced through COX-2 in the inflammatory cascade. Interestingly, we found that COX-2-associate PGE(2) production activated by influenza virus infection was significantly suppressed by over-expression of IL-32 but increased by IL-32-specific siRNA, suggesting there was a feedback mechanism between IL-32 and COX-2.IL-32 is induced by influenza A virus infection via COX-2 in the inflammatory cascade. Our results provide that IL-32 is a potential target for anti-inflammatory medicine screening.

In this study, we characterized the miR482 family in cotton using existing small RNA datasets and the recently released draft genome sequence of Gossypium raimondii, a diploid cotton species whose progenitor is the putative contributor of the Dt (representing the D genome of tetraploid) genome of the cultivated tetraploid cotton species G. hirsutum and G. barbadense. Of the three ghr-miR482 members reported in G. hirsutum, ghr-miR482a has no homolog in G. raimondii, ghr-miR482b and ghr-miR482c each has a single homolog in G. raimondii. Gra-miR482d has five homologous loci (gra-miR482d, f-i) in G. raimondii and also exists in G. hirsutum (ghr-miR482d). A variant, miR482.2 that is a homolog of miR2118 in other species, is produced from several GHR-MIR482 loci in G. hirsutum. Approximately 12% of the G. raimondii NBS-LRR genes were predicted targets of various members of the gra-miR482 family. Based on the rationale that the regulatory relationship between miR482 and NBS-LRR genes will be conserved in G. raimondii and G. hirsutum, we investigated this relationship using G. hirsutum miR482 and G. raimondii NBS-LRR genes, which are not currently available in G. hirsutum. Ghr-miR482/miR482.2-mediated cleavage was confirmed for three of the four NBS-LRR genes analysed. As in tomato, miR482-mediated cleavage of NBS-LRR genes triggered production of phased secondary small RNAs in cotton. In seedlings of the susceptible cultivar Sicot71 (G. hirsutum) infected with the fungal pathogen Verticillium dahliae, the expression levels of ghr-miR482b/miR482b.2, ghr-miR482c and ghr-miR482d.2 were down-regulated, and several NBS-LRR targets of ghr-miR482c and ghr-miR482d were up-regulated. These results imply that, like tomato plants infected with viruses or bacteria, cotton plants are able to induce expression of NBS-LRR defence genes by suppression of the miRNA-mediated gene silencing pathway upon fungal pathogen attack. [ABSTRACT FROM AUTHOR]