tailieunhanh - Báo cáo sinh học: " An expanded evolutionary role for flower symmetry genes"

Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học Journal of Biology đề tài: An expanded evolutionary role for flower symmetry genes. | Journal of Biology Minireview An expanded evolutionary role for flower symmetry genes Lena C Hileman and Pilar Cubast Addresses Department of Ecology and Evolutionary Biology University of Kansas 1200 Sunnyside Ave Lawrence Kansas 66045 USA. tDepartamento de Genética Molecular de Plantas Centro Nacional de Biotecnología CSIC Campus Universidad Autónoma de Madrid 28049 Madrid Spain. Correspondence Lena C Hileman. Email lhileman@ Abstract CYCLOIDEA CYC -like TCP genes are critical for flower developmental patterning. Exciting recent breakthroughs including a study by Song et al. published in BMC Evolutionary Biology demonstrate that CYC-like genes have also had an important role in the evolution of flower form. See research article http 1471-2148 9 244. Across the flowering plants the angiosperms bilaterally symmetrical zygomorphic flowers are thought to have evolved many times independently from radially symmetrical actinomorphic ancestors. Transitions to bilateral flower symmetry have been associated with the evolution of specialized pollinators and have been crucial in the diversification of flowering plants. Zygomorphic flowers have dorsal adaxial organs that are morphologically different from ventral abaxial ones Figure 1a . Asymmetry along the dorsoventral axis is most evident in the petal and stamen whorls. Bilaterally symmetrical corollas petal whorls help promote the approach of pollinators from one particular orientation. In addition the dorsal-most and or ventral stamens are often aborted leaving only a rudimentary stamen staminode Figure 1a . This can facilitate access to the remaining stamens by pollinators or increase the specificity of pollen deposition during pollinator visits. Groundbreaking comparative studies over the past few years have demonstrated that CYCLOIDEA CYC -like genes which belong to the class II TCP family of transcription factors have been recruited multiple times to pattern dorsal flower identity in core