Jofuku K D, den Boer B G, Van Montagu M, Okamuro J K
Sinsheimer Laboratories, Department of Biology, University of California, Santa Cruz 95064.
Plant Cell. 1994 Sep;6(9):1211-25. doi: 10.1105/tpc.6.9.1211.
APETALA2 (AP2) plays a central role in the establishment of the floral meristem, the specification of floral organ identity, and the regulation of floral homeotic gene expression in Arabidopsis. We show here that in addition to its functions during flower development, AP2 activity is also required during seed development. We isolated the AP2 gene and found that it encodes a putative nuclear protein that is distinguished by an essential 68-amino acid repeated motif, the AP2 domain. Consistent with its genetic functions, we determined that AP2 is expressed at the RNA level in all four types of floral organs--sepals, petals, stamens, and carpels--and in developing ovules. Thus, AP2 gene transcription does not appear to be spatially restricted by the floral homeotic gene AGAMOUS as predicted by previous studies. We also found that AP2 is expressed at the RNA level in the inflorescence meristem and in nonfloral organs, including leaf and stem. Taken together, our results suggest that AP2 represents a new class of plant regulatory proteins that may play a general role in the control of Arabidopsis development.
APETALA2（AP2）在拟南芥花分生组织的建立、花器官特征的决定以及花同源异型基因表达的调控中起着核心作用。我们在此表明，除了在花发育过程中的功能外，种子发育过程中也需要AP2的活性。我们分离出了AP2基因，发现它编码一种推定的核蛋白，其特征是具有一个由68个氨基酸组成的必需重复基序，即AP2结构域。与其遗传功能一致，我们确定AP2在所有四种花器官——萼片、花瓣、雄蕊和心皮——以及发育中的胚珠中以RNA水平表达。因此，AP2基因转录似乎不像先前研究所预测的那样受到花同源异型基因AGAMOUS的空间限制。我们还发现AP2在花序分生组织以及包括叶和茎在内的非花器官中以RNA水平表达。综上所述，我们的结果表明AP2代表了一类新的植物调节蛋白，可能在拟南芥发育的控制中发挥普遍作用。
