您选择的条件: 2023-2
  • A new specimen of Parabohaiornis martini (Avialae: Enantiornithes) sheds light on early avian skull evolution

    分类: 生物学 >> 动物学 提交时间: 2023-02-17 合作期刊: 《古脊椎动物学报》

    摘要: The Enantiornithes is the most speciose clade of Mesozoic avialans with over 60 named taxa reported from most continents that span the whole Cretaceous. Most of the fossil remains of this clade, as well as those of other early diverging avialans are preserved in twodimensions. This complicates to extract detailed anatomical information from the skull, in which the composite elements are delicate and thus not easily observable through conventional methods. The scarcity of well-preserved early avialan skulls, as well as the limited number of specimens that have been analyzed using computed tomography scanning, consequently circumscribes a large morphological gap in the fossil record during the transition from the heavy and akinetic dinosaurian skull to the lightweight and kinetic bird skull. Here, we present a threedimensional digital reconstruction of the skull and part of the cervical vertebrae of a new specimen of the enantiornithine Parabohaiornis martini from the Early Cretaceous of China. Our results demonstrate that Parabohaiornis retains the plesiomorphic non-avialan dinosaurian temporal and palatal reinforcing the recent hypothesis that the temporal and palatal regions are evolutionarily conservative and that the akinetic skull has been conserved well into of early branching avialans.

  • CropCircDB: a comprehensive circular RNA resource for crops in response to abiotic stress

    分类: 生物学 >> 生物学其他学科 分类: 计算机科学 >> 计算机应用技术 提交时间: 2023-02-09

    摘要: Circular RNA (circRNAs) may mediate mRNA expression as miRNA sponge. Since the community has paid more attention on circRNAs, a lot of circRNA databases have been developed for plant. However, a comprehensive collection of circRNAs in crop response to abiotic stress is still lacking. In this work, we applied a big-data approach to take full advantage of large-scale sequencing data, and developed a rich circRNA resource: CropCircDB for maize and rice, later extending to incorporate more crop species. We also designed a metric: stress detections score, which is specifically for detecting circRNAs under stress condition. In summary, we systematically investigated 244 and 288 RNASeq samples for maize and rice, respectively, and found 38 785 circRNAs in maize, and 63 048 circRNAs in rice. This resource not only supports user-friendly JBrowser to visualize genome easily, but also provides elegant view of circRNA structures and dynamic profiles of circRNA expression in all samples. Together, this database will host all predicted and validated crop circRNAs response to abiotic stress.