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排序方式: 共有196条查询结果,搜索用时 31 毫秒
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Abstract We experimentally studied con-specific interference in Ibalia leucospoides, a parasitoid of the woodwasp Sirex noctilio, on pine logs containing variable numbers of woodwasp larvae. Competiton occurred when two different-sized female parasitoids foraged on a host patch, and consequently the small female always abandoned the patch. Regardless of host density, con-specific presence did not affect the attack rate, the number of hosts attacked, nor patch residence time by the winner, when compared to a control female that foraged alone. In contrast, con-specific presence reduced patch time and the number of hosts attacked by the loser. Finally patch time (by both) as well as number of hosts attacked (by the winner only) increased with host density per patch. Our results suggest that con-specific presence has different consequences for different-sized females during patch exploitation. 相似文献
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Beetle 'horns' are rigid outgrowths of the insect cuticle used as weapons in contests for access to mates. Relative to their body size, beetle horns can be enormous. They protrude from any of five different regions of the head or thorax; they are curved, straight, branched or bladed; and their development is often coupled with the nutrient environment (male dimorphism) or with sex (sexual dimorphism). Here, we show that this extraordinary diversity of horns can be distilled down to four trajectories of morphological change--horn location, shape, allometry and dimorphism--and we illustrate how the developmental mechanisms regulating horn growth could generate each of these types of horn evolution. Specifically, we review two developmental pathways known to regulate growth of morphological structures in Drosophila and other insects: a limb-patterning pathway that specifies the location and shape of a structure, and the insulin pathway, which modulates trait growth in response to larval nutrition. We summarize preliminary evidence indicating that these pathways are associated with the development of beetle horns, and we show how subtle changes in the relative activities of these two pathways would be sufficient to generate most of the extant diversity of horn forms. Our objective is to intuitively connect genotype with phenotype, and to advocate an informed 'candidate gene' approach to studies of the developmental basis of evolution. We end by using this insight from development to offer a solution to the long-standing mystery of the scarabs: the observation by Darwin, Lameere, Arrow and others that this one family of beetles appeared to have a 'special tendency' towards the evolution of horns. 相似文献
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Michael J. Corley Carlo Sacdalan Alina P. S. Pang Nitiya Chomchey Nisakorn Ratnaratorn Victor Valcour Eugene Kroon Kyu S. Cho Andrew C. Belden Donn Colby Merlin Robb Denise Hsu Serena Spudich Robert Paul Sandhya Vasan Lishomwa C. Ndhlovu the SEARCH/RV SEARCH/RV study groups 《PLoS pathogens》2021,17(8)
HIV-1 disrupts the host epigenetic landscape with consequences for disease pathogenesis, viral persistence, and HIV-associated comorbidities. Here, we examined how soon after infection HIV-associated epigenetic changes may occur in blood and whether early initiation of antiretroviral therapy (ART) impacts epigenetic modifications. We profiled longitudinal genome-wide DNA methylation in monocytes and CD4+ T lymphocytes from 22 participants in the RV254/SEARCH010 acute HIV infection (AHI) cohort that diagnoses infection within weeks after estimated exposure and immediately initiates ART. We identified monocytes harbored 22,697 differentially methylated CpGs associated with AHI compared to 294 in CD4+ T lymphocytes. ART minimally restored less than 1% of these changes in monocytes and had no effect upon T cells. Monocyte DNA methylation patterns associated with viral load, CD4 count, CD4/CD8 ratio, and longitudinal clinical phenotypes. Our findings suggest HIV-1 rapidly embeds an epigenetic memory not mitigated by ART and support determining epigenetic signatures in precision HIV medicine.Trial Registration: and NCT00782808. NCT00796146相似文献
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Sunil S. Gangurde Hui Wang Shasidhar Yaduru Manish K. Pandey Jake C. Fountain Ye Chu Thomas Isleib C. Corley Holbrook Alencar Xavier Albert K. Culbreath Peggy Ozias‐Akins Rajeev K. Varshney Baozhu Guo 《Plant biotechnology journal》2020,18(6):1457-1471
Multiparental genetic mapping populations such as nested‐association mapping (NAM) have great potential for investigating quantitative traits and associated genomic regions leading to rapid discovery of candidate genes and markers. To demonstrate the utility and power of this approach, two NAM populations, NAM_Tifrunner and NAM_Florida‐07, were used for dissecting genetic control of 100‐pod weight (PW) and 100‐seed weight (SW) in peanut. Two high‐density SNP‐based genetic maps were constructed with 3341 loci and 2668 loci for NAM_Tifrunner and NAM_Florida‐07, respectively. The quantitative trait locus (QTL) analysis identified 12 and 8 major effect QTLs for PW and SW, respectively, in NAM_Tifrunner, and 13 and 11 major effect QTLs for PW and SW, respectively, in NAM_Florida‐07. Most of the QTLs associated with PW and SW were mapped on the chromosomes A05, A06, B05 and B06. A genomewide association study (GWAS) analysis identified 19 and 28 highly significant SNP–trait associations (STAs) in NAM_Tifrunner and 11 and 17 STAs in NAM_Florida‐07 for PW and SW, respectively. These significant STAs were co‐localized, suggesting that PW and SW are co‐regulated by several candidate genes identified on chromosomes A05, A06, B05, and B06. This study demonstrates the utility of NAM population for genetic dissection of complex traits and performing high‐resolution trait mapping in peanut. 相似文献
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Elaine M. Sandeman Maria del Carmen Valdes Hernandez Zoe Morris Mark E. Bastin Catherine Murray Alan J. Gow Janie Corley Ross Henderson Ian J. Deary John M. Starr Joanna M. Wardlaw 《PloS one》2013,8(8)