Purugganan M D, Suddith J I
Department of Genetics, Box 7614, North Carolina State University, Raleigh, NC 27695, USA.
Proc Natl Acad Sci U S A. 1998 Jul 7;95(14):8130-4. doi: 10.1073/pnas.95.14.8130.
The evolution of interspecies differences in morphology requires sufficient within-species variation in developmental regulatory systems on which evolutionary forces can act. Molecular analyses of naturally occurring alleles of the Arabidopsis thaliana CAULIFLOWER locus reveal considerable intraspecific diversity at this floral homeotic gene, and the McDonald-Kreitman test suggests that this gene is evolving in a nonneutral fashion, with an excess of intraspecific replacement polymorphisms. The naturally occurring molecular variation within this floral regulatory gene is associated with functionally different alleles, which can be distinguished phenotypically by their differential ability to direct floral meristem development.
物种间形态差异的演变需要发育调控系统在物种内部有足够的变异，以便进化力量能够作用于其上。对拟南芥花椰菜基因座自然存在的等位基因进行分子分析，揭示了这个花同源异型基因存在相当大的种内多样性，并且麦克唐纳-克里特曼检验表明该基因正以非中性方式进化，种内替换多态性过多。这个花调控基因内自然存在的分子变异与功能不同的等位基因相关，这些等位基因可以通过它们指导花分生组织发育的不同能力在表型上加以区分。
