Luo D, Carpenter R, Vincent C, Copsey L, Coen E
Genetics Department, John Innes Centre, Norwich, UK.
Nature. 1996 Oct 31;383(6603):794-9. doi: 10.1038/383794a0.
Dorsoventral asymmetry in flowers is thought to have evolved many times from a radially symmetrical ancestral condition. The first gene controlling floral asymmetry, cycloidea in Antirrhinum, has been isolated. The cycloidea gene is expressed at a very early stage in dorsal regions of floral meristems, where it affects growth rate and primordium initiation. Expression continues through to later stages in dorsal primordia to affect the asymmetry, size and cell types of petals and stamens.
花朵的背腹不对称性被认为是从辐射对称的祖先状态多次进化而来的。第一个控制花不对称性的基因，即金鱼草中的cycloidea基因，已被分离出来。cycloidea基因在花分生组织的背部区域的非常早期阶段表达，在那里它影响生长速率和原基起始。表达持续到背部原基的后期阶段，以影响花瓣和雄蕊的不对称性、大小和细胞类型。
