Chen Lin, Zhang Shuiming, Illa Eudald, Song Lijuan, Wu Shandong, Howad Werner, Arús Pere, van de Weg Eric, Chen Kunsong, Gao Zhongshan
Institute of Fruit Science, The State Agriculture Ministry Laboratory of Horticultural Plant Growth, Development and Biotechnology, Zhejiang University, Hangzhou, 310029, PR China.
BMC Genomics. 2008 Nov 17;9:543. doi: 10.1186/1471-2164-9-543.
Fruits from several species of the Rosaceae family are reported to cause allergic reactions in certain populations. The allergens identified belong to mainly four protein families: pathogenesis related 10 proteins, thaumatin-like proteins, lipid transfer proteins and profilins. These families of putative allergen genes in apple (Mal d 1 to 4) have been mapped on linkage maps and subsequent genetic study on allelic diversity and hypoallergenic traits has been carried out recently. In peach (Prunus persica), these allergen gene families are denoted as Pru p 1 to 4 and for almond (Prunus dulcis)Pru du 1 to 4. Genetic analysis using current molecular tools may be helpful to establish the cause of allergenicity differences observed among different peach cultivars. This study was to characterize putative peach allergen genes for their genomic sequences and linkage map positions, and to compare them with previously characterized homologous genes in apple (Malus domestica).
Eight Pru p/du 1 genes were identified, four of which were new. All the Pru p/du 1 genes were mapped in a single bin on the top of linkage group 1 (G1). Five Pru p/du 2 genes were mapped on four different linkage groups, two very similar Pru p/du 2.01 genes (A and B) were on G3, Pru p/du 2.02 on G7,Pru p/du 2.03 on G8 and Pru p/du 2.04 on G1. There were differences in the intron and exon structure in these Pru p/du 2 genes and in their amino acid composition. Three Pru p/du 3 genes (3.01-3.03) containing an intron and a mini exon of 10 nt were mapped in a cluster on G6. Two Pru p/du 4 genes (Pru p/du 4.01 and 4.02) were located on G1 and G7, respectively. The Pru p/du 1 cluster on G1 aligned to the Mal d 1 clusters on LG16; Pru p/du 2.01A and B on G3 to Mal d 2.01A and B on LG9; the Pru p/du 3 cluster on G6 to Mal d 3.01 on LG12; Pru p/du 4.01 on G1 to Mal d 4.03 on LG2; and Pru p/du 4.02 on G7 to Mal d 4.02 on LG2.
A total of 18 putative peach/almond allergen genes have been mapped on five linkage groups. Their positions confirm the high macro-synteny between peach/almond and apple. The insight gained will help to identify key genes causing differences in allergenicity among different cultivars of peach and other Prunus species.
据报道，蔷薇科几种植物的果实会在特定人群中引发过敏反应。已鉴定出的过敏原主要属于四个蛋白质家族：病程相关蛋白10、类thaumatin蛋白、脂质转移蛋白和肌动蛋白结合蛋白。苹果（Mal d 1至4）中这些假定的过敏原基因家族已被定位到连锁图谱上，并且最近对其等位基因多样性和低过敏原性状进行了遗传研究。在桃（Prunus persica）中，这些过敏原基因家族被命名为Pru p 1至4，杏仁（Prunus dulcis）中则为Pru du 1至4。使用当前分子工具进行遗传分析可能有助于确定不同桃品种间观察到的过敏原性差异的原因。本研究旨在表征假定的桃过敏原基因的基因组序列和连锁图谱位置，并将它们与苹果（Malus domestica）中先前表征的同源基因进行比较。
鉴定出8个Pru p/du 1基因，其中4个是新基因。所有Pru p/du 1基因都定位在连锁群1（G1）顶部的一个单一区间内。5个Pru p/du 2基因定位在4个不同的连锁群上，两个非常相似的Pru p/du 2.01基因（A和B）位于G3上，Pru p/du 2.02位于G7上，Pru p/du 2.03位于G8上，Pru p/du 2.04位于G1上。这些Pru p/du 2基因在其内含子和外显子结构以及氨基酸组成上存在差异。3个含有一个内含子和一个10 nt小外显子的Pru p/du 3基因（3.01 - 3.03）定位在G6上的一个簇中。2个Pru p/du 4基因（Pru p/du 4.01和4.02）分别位于G1和G7上。G1上的Pru p/du 1簇与LG16上的Mal d 1簇对齐；G3上的Pru p/du 2.01A和B与LG9上的Mal d 2.01A和B对齐；G6上的Pru p/du 3簇与LG12上的Mal d 3.01对齐；G1上的Pru p/du 4.01与LG2上的Mal d 4.03对齐；G7上的Pru p/du 4.02与LG2上的Mal d 4.02对齐。
总共18个假定的桃/杏仁过敏原基因已定位在5个连锁群上。它们的位置证实了桃/杏仁与苹果之间高度的宏观共线性。所获得的见解将有助于识别导致不同桃品种和其他李属物种间过敏原性差异的关键基因。
