被子植物的早期胚胎形态建成

Research Progress on Early Embryogenesis in Angiosperms

被子植物早期胚胎形态建成是其有性生殖过程中一个重要发育阶段。在这一阶段中,被子植物形体基本特征形成,包括顶-基轴极性建立、不同细胞层分化以及分生组织形成。合子极性直接与顶基细胞命运相关,但其极性产生机理仍然不明。研究表明,WOX家族转录因子、生长素定向运输以及生长素响应应答可能参与了早期顶-基模型建成;辐射对称模型的建立可能由细胞与细胞间相互作用来介导;生长素流可能参与胚胎顶端组织形成。该文对近年来被子植物早期胚胎形态建成过程中的合子极性建立与生长、合子分裂及其顶基细胞的形成、胚根原特化及根极的形成、辐射对称模式及表皮原特化、顶端分生组织特化及子叶起始等方面的研究进展进行了综述。

Early embryogenesis in angiosperms is an important developmental stage of sexual reproductive process. At this stage, the basic morphology of seedling is established, including apical-basal axial polarity, different cell layers differentiation,and meristem formation. Zygote polarity directly affects the cell fates of apical and basal cell,but the underlying mechanism is still unknown. Previous studies suggested that WOX family transcription factors, direct auxin transportation as well as auxin response may be involved in the es- tablishment of apical-basal patterning. Cell-cell communication may mediate the radial patterning. Addition- ally, auxin flow participates in the process of apical organization. This paper will review the late research progresses on early embryogenesis of angiosperms,including zygote polarity and elongation,zygote division and apical and basal cell formation,hypophysis specification and root pole formation, radial patterning and protoderm specification,shoot meristem specification and cotyledon initiation.