桃是世界上分布最廣泛的栽培果樹之一,，位居落葉果樹前3位,，其鮮果食用、果汁和罐頭加工制品一直深受消費(fèi)者喜愛,。隨著社會(huì)對其果實(shí)和相關(guān)制品需求量的進(jìn)一步增加,，如何高效快速地培育優(yōu)良桃品種是目前產(chǎn)業(yè)發(fā)展的瓶頸。因此,，開展桃的功能基因組學(xué)研究,，無疑有助于促進(jìn)育種和產(chǎn)業(yè)的發(fā)展。
中科院武漢植物園果樹分子育種學(xué)科組深入開展了桃功能基因組學(xué)研究,，并取得一系列進(jìn)展,。該課題組王魯研究人員通過RNA-seq測序技術(shù)，進(jìn)行了目前文獻(xiàn)報(bào)道的桃的最高通量轉(zhuǎn)錄組測序,。該項(xiàng)目建成不同品種花,、葉、果等組織的11個(gè)RNA樣品庫,，完成21.5G的測序量,，獲得含有完整編碼區(qū)序列信息的基因超過25000個(gè)，其中超過2000個(gè)在桃基因組測序和注釋中未被發(fā)現(xiàn),，屬于新發(fā)現(xiàn)的基因,。相關(guān)基因的可變剪切形式,、表達(dá)量均得到了充分的分析結(jié)果。另外從全部的轉(zhuǎn)錄基因序列信息中分析得到簡單重復(fù)序列（SSR分子標(biāo)記）17979個(gè),；各不同基因型之間對比得到的SNP分子標(biāo)記約一萬個(gè),。這些序列信息、表達(dá)情況以及分子標(biāo)記將有助于通過遺傳圖譜進(jìn)行桃的關(guān)鍵農(nóng)藝性狀QTL定位,，并開發(fā)與優(yōu)異性狀緊密連鎖的分子標(biāo)記,，應(yīng)于用桃分子標(biāo)記輔助育種。相關(guān)論文以Deep RNA-Seq uncovers the peach transcriptome landscape為題發(fā)表于國際植物期刊《植物分子生物學(xué)》（Plant Molecular Biology）上,。
同時(shí),，該學(xué)科組通過對紅葉桃、普通桃相關(guān)基因序列,、表達(dá)情況的比較分析,，發(fā)現(xiàn)光呼吸相關(guān)的信號通路部分基因（GDCH 和GOX）在遮光、熱脅迫處理以后表達(dá)量上升,，而花青素相關(guān)的結(jié)構(gòu)與調(diào)節(jié)基因則呈下降趨勢,。在擬南芥的花青素合成結(jié)構(gòu)基因chi的突變體中發(fā)現(xiàn)，雖然該突變體不能積累花青素,，但在相關(guān)條件下,，GDCH 和GOX基因同樣出現(xiàn)表達(dá)上調(diào)。這些結(jié)果表明光呼吸信號途徑中的部分基因可能是花青素合成和積累途徑的拮抗調(diào)節(jié)因子,。該結(jié)果發(fā)表在林業(yè)科學(xué)SCI期刊Tree Genetics & Genomes（JCR專業(yè)領(lǐng)域排名top10%）上,。
圖1 桃轉(zhuǎn)錄組基因和轉(zhuǎn)錄因子的分類及其組織表達(dá)特性
圖2 紅葉桃葉不同發(fā)育時(shí)期中花青素含量及相關(guān)代謝途徑基因的動(dòng)態(tài)變化
生物谷推薦的英文摘要
Tree Genetics & Genomes DOI 10.1007/s11295-012-0552-1
Coordinated regulation of anthocyanin biosynthesis through photorespiration and temperature in peach (Prunus persica f. atropurpurea)
Ying Zhou, Dong Guo, Jing Li, Jun Cheng, Hui Zhou, Chao Gu, Sue Gardiner, Yue-Peng Han
The usual red color of young leaves of peach (Prunus persica f. atropurpurea) is due to the accumulation of anthocyanin. Real-time PCR analysis revealed a strong correlation between the expression levels of anthocyanin biosynthetic genes and anthocyanin content in leaves at different developmental stages. The expression profiles of both anthocyanin biosynthetic genes and photorespiratory genes showed significant changes in leaves held in the dark or exposed to heat stress, compared with controls. The expression of anthocyanin biosynthetic genes dramatically decreased in peach red leaves following dark or heat treatments, resulting in a significant decrease of anthocyanin accumulation. However, the photorespiration-related genes GDCH and GOX exhibited increased expression in peach leaves after dark or heat treatment. Moreover, the expression levels of GDCH and GOX in the Arabidopsis chi/f3′h mutant that does not accumulate anthocyanins were higher than in the wild type. Overall, these results support the hypothesis that photorespiration-related genes might be involved in the regulation of anthocyanin biosynthesis. This finding provides a new insight into our understanding of the mechanism underlying the control of anthocyanin biosynthesis in plants.
