Anthocyanin biosynthesis and accumulation in developing flowers of tree peony (Paeonia suffruticosa) 'Luoyang Hong'
Anthocyanin biosynthesis and accumulation in developing flowers of tree peony (Paeonia suffruticosa) 'Luoyang Hong'
复制标题
DOI：
10.1016/j.postharvbio.2014.05.019
复制
发表时间：
2014-11-01
影响因子：
7
通讯作者：
Dong, Li
中科院分区：
文献类型：
--
作者：
Zhang, Chao;Wang, Weining;Dong, Li
牡丹‘洛阳红’是我国牡丹品种中最受中国人喜爱的紫红色牡丹品种。然而，‘洛阳红’瓶内花并不像树上的花那样表现出自然的花色，因为用肉眼很容易观察到瓶内花的褪色。本研究旨在揭示瓶插牡丹‘洛阳红’褪色的分子机理。根据转录组文库，从‘洛阳红’花瓣中分离到5个花青素生物合成调控基因和6个花青素合成相关结构基因。与大田条件下完全开放的树上花相比，‘洛阳红’盛开期的瓶内花(瓶插温度21~23℃，相对湿度50~60%，光照16h，光照接近40 mU/m(-2)S(-1))，中部花瓣无斑点部分(第4~6层花瓣)的亮度增加50.20%，红度减少37.43%，色度减少36.18%，褪色显著。开花前至盛花期，瓶插花内、中、外花瓣花色苷含量比树上发育花低24.49~38.75%。除PsCHI1外，其他10个花青素生物合成基因在花组织(花瓣、花瓣、雄蕊或心皮)中高水平优先表达。花青素生物合成基因在树上和瓶插花中的时间表达分析表明，只有PsF3‘H1的表达模式与花青素含量的发育相关。总体而言，‘洛阳红’的PsbHLH3、PsWD40-1、PsWD40-2、PsMYB2、PsCHS1、PsF3H1和PsDFR1基因在瓶内花中的转录丰度均低于树上花，表明这些基因的低表达可能与花青素含量较低，导致瓶内花的花瓣褪色有关。(C)2014爱思唯尔B.V.保留所有权利。
Tree peony (Paeonia suffruticosa) 'Luoyang Hong', a typical purplish red-flowered cultivar, is particularly appreciated by Chinese among the hundreds of cultivars. However, in-vase 'Luoyang Hong' flowers do not exhibit natural flower color as shown by on-tree flowers, since color fading of in-vase flowers is easily observed with the naked eye. This study was carried out to reveal the underlying molecular mechanism of color fading of in-vase P. suffruticosa 'Luoyang Hong'. Five regulatory genes and six structural genes involved in anthocyanin biosynthesis were isolated based on a transcriptome library from P. suffruticosa 'Luoyang Hong' petals. Compared with fully opened on-tree flowers in field conditions, in-vase flowers (vase condition of 21-23 degrees C, 50-60% RH and a 16 h photoperiod with an illumination of similar to 40 mu mol m(-2) s(-1)) of P. suffruticosa 'Luoyang Hong' at full opening stage show significant color fading with 50.20% greater lightness, 37.43% less redness and 36.18% lower chroma in non-blotch parts of the middle petals (the 4th to 6th layer petal). From pre-opening to full opening stage, anthocyanin contents in inner, middle and outer petals of in-vase flowers was 24.49-38.75% lower than those in on-tree developing flowers. With the exception of PsCHI1, another ten anthocyanin biosynthetic genes were preferentially and highly expressed in floral tissues (sepals, petals, stamens or carpels). Temporal expression analysis of anthocyanin biosynthetic genes in on-tree and in-vase developing flowers revealed that only the expression pattern of PsF3'H1 was correlated with anthocyanin content development. On the whole, PsbHLH3, PsWD40-1, PsWD40-2, PsMYB2,PsCHS1, PsF3H1 and PsDFR1 of P. suffruticosa 'Luoyang Hong' showed lower transcript abundances in in-vase flowers than in on-tree flowers, suggesting that the low expression of these genes is probably responsible for lower anthocyanin contents, resulting in the color fading in the petals in in-vase flowers. (C) 2014 Elsevier B.V. All rights reserved.