Apple Breeding and Physiology Research Team, National Institute of Fruit Tree Science, Morioka 020-0123, Japan.
Tree Physiol. 2011 May;31(5):555-66. doi: 10.1093/treephys/tpr028. Epub 2011 May 12.
Understanding the flowering process in apple (Malus × domestica Borkh.) is essential for developing methods to shorten the breeding period and regulate fruit yield. It is known that FLOWERING LOCUS T (FT) acts as a transmissible floral inducer in the Arabidopsis flowering network system. To clarify the molecular network of two apple FT orthologues, MdFT1 and MdFT2, we performed a yeast two-hybrid screen to identify proteins that interact with MdFT1. We identified several transcription factors, including two members of the TCP (TEOSINTE BRANCHED1, CYCLOIDEA and PROLIFERATING CELL FACTORs) family, designated MdTCP2 and MdTCP4, and an Arabidopsis thaliana VOZ1 (Vascular plant One Zinc finger protein1)-like protein, designated MdVOZ1. MdTCP2 and MdVOZ1 also interacted with MdFT2 in yeast. The expression domain of MdTCP2 and MdVOZ1 partially overlapped with that of MdFT1 and MdFT2, most strikingly in apple fruit tissue, further suggesting a potential interaction in vivo. Constitutive expression of MdTCP2, MdTCP4 and MdVOZ1 in Arabidopsis affected plant size, leaf morphology and the formation of leaf primordia on the adaxial side of cotyledons. On the other hand, chimeric MdTCP2, MdTCP4 and MdVOZ1 repressors that included the ethylene-responsive transcription factors (ERF)-associated amphiphilic repression (EAR) domain motif influenced reproduction and inflorescence architecture in transgenic Arabidopsis. These results suggest that MdFT1 and/or MdFT2 might be involved in the regulation of cellular proliferation and the formation of new tissues and that they might affect leaf and fruit development by interacting with TCP- and VOZ-family proteins. DDBJ accession nos. AB531019 (MdTCP2a mRNA), AB531020 (MdTCP2b mRNA), AB531021 (MdTCP4a mRNA), AB531022 (MdTCP4b mRNA) and AB531023 (MdVOZ1a mRNA).
了解苹果（Malus × domestica Borkh.）的开花过程对于开发缩短育种周期和调节果实产量的方法至关重要。已知 FLOWERING LOCUS T（FT）在拟南芥开花网络系统中充当可传递的花诱导剂。为了阐明两个苹果 FT 同源物 MdFT1 和 MdFT2 的分子网络，我们进行了酵母双杂交筛选以鉴定与 MdFT1 相互作用的蛋白质。我们鉴定了几种转录因子，包括 TCP（TEOSINTE BRANCHED1、CYCLOIDEA 和 PROLIFERATING CELL FACTORs）家族的两个成员，命名为 MdTCP2 和 MdTCP4，以及拟南芥 VOZ1（血管植物一个锌指蛋白 1）样蛋白，命名为 MdVOZ1。MdTCP2 和 MdVOZ1 也在酵母中与 MdFT2 相互作用。MdTCP2 和 MdVOZ1 的表达域与 MdFT1 和 MdFT2 的表达域部分重叠，最显著的是在苹果果实组织中，进一步表明体内存在潜在的相互作用。在拟南芥中组成型表达 MdTCP2、MdTCP4 和 MdVOZ1 会影响植株大小、叶片形态以及子叶上侧叶原基的形成。另一方面，包含乙烯响应转录因子（ERF）相关的双嗜性抑制（EAR）基序的嵌合 MdTCP2、MdTCP4 和 MdVOZ1 抑制剂影响转基因拟南芥的繁殖和花序结构。这些结果表明，MdFT1 和/或 MdFT2 可能参与细胞增殖和新组织形成的调节，并且它们可能通过与 TCP 和 VOZ 家族蛋白相互作用影响叶片和果实发育。DDBJ 登录号 AB531019（MdTCP2a mRNA）、AB531020（MdTCP2b mRNA）、AB531021（MdTCP4a mRNA）、AB531022（MdTCP4b mRNA）和 AB531023（MdVOZ1a mRNA）。
