Department of Pomology, College of Horticulture, China Agricultural University, Yuanmingyuan West Road No. 2, Haidian District, Beijing 100193, PR China.
Plant Physiol Biochem. 2018 Apr;125:136-142. doi: 10.1016/j.plaphy.2017.12.006. Epub 2017 Dec 6.
Arabidopsis SUPERMAN and its family members of its family play important roles in plant growth and floral organ development; yet much less is known about their functions expanding in apple tree development. Previous work has identified 12 SUP-like genes in the apple (Malus × domestica Borkh.) genome, and the MdSUP11 which is expressed in both vegetative and reproductive organs of apple. However, the function of MdSUP11 remains obscure. In this study, the β-glucuronidase expression driven by the MdSUP11 native promoter was detected in roots, young leaves, and floral organs of transgenic Arabidopsis. In transgenic tobacco, overexpression of MdSUP11 lead to dwarfism, aberrant leaf shapes, and morphological changes of floral organs. Endogenous concentrations of auxin (indole-3-acetic acid), abscisic acid, isopentenyl adenosine and zeatin riboside were significantly higher in young MdSUP11-transformed tobacco plants than in non-transformed plants. Gene expression analysis using real-time quantitative PCR showed up-regulation of NtDFR2 and NtANS1 expression in unopened transgenic flowers, whereas NtCHS expression was not changed significantly. Together, these results suggest that MdSUP11 is associated with apple's vegetative and reproductive development. Its overexpression in tobacco affects leaf and flower organ development and plant height; potentially by changing NtDFR2 and NtANS1 expression and endogenous levels of indole-3-acetic acid, cytokinins and abscisic acid.
拟南芥 SUPERMAN 及其家族成员在植物生长和花器官发育中发挥重要作用；然而，关于它们在苹果树上发育中的功能扩展，人们知之甚少。先前的工作已经在苹果（Malus × domestica Borkh.）基因组中鉴定出 12 个 SUP 样基因，其中 MdSUP11 在苹果的营养器官和生殖器官中都有表达。然而，MdSUP11 的功能仍不清楚。在这项研究中，用 MdSUP11 天然启动子驱动的β-葡萄糖醛酸酶表达在转基因拟南芥的根、幼叶和花器官中被检测到。在转基因烟草中，MdSUP11 的过表达导致矮化、叶片形状异常和花器官形态改变。未转化烟草中内源生长素（吲哚-3-乙酸）、脱落酸、异戊烯腺苷和玉米素核苷的浓度明显高于年轻的 MdSUP11 转化烟草植株。使用实时定量 PCR 的基因表达分析显示，在未开放的转基因花朵中 NtDFR2 和 NtANS1 的表达上调，而 NtCHS 的表达没有明显变化。总之，这些结果表明 MdSUP11 与苹果的营养和生殖发育有关。其在烟草中的过表达影响叶片和花器官的发育和株高；可能通过改变 NtDFR2 和 NtANS1 的表达和内源吲哚-3-乙酸、细胞分裂素和脱落酸的水平。
