種質(zhì)資源庫可以最大限度地延長(zhǎng)耐脫水種子(即正常型種子)的壽命,,例如玉米種子在昆明室溫僅能保藏1年半,而在種質(zhì)資源庫的條件下卻能保藏近2000年。然而,即使是如此優(yōu)越的保藏條件,種子最終還是將面臨死亡,,因此,解析種子老化過程對(duì)于種質(zhì)資源庫的保藏是至關(guān)重要的,。中國(guó)科學(xué)院昆明植物研究所種質(zhì)資源庫種子生物學(xué)研究組陳虹穎博士與英國(guó)專家合作,,對(duì)豌豆種子老化過程中種子活力與基因表達(dá)以及谷胱甘肽氧化還原狀態(tài)之間的關(guān)系進(jìn)行了檢測(cè)分析。
該研究采用基因芯片以及實(shí)時(shí)定量PCR技術(shù)對(duì)種子老化過程中的轉(zhuǎn)錄水平表達(dá)進(jìn)行了檢測(cè),。結(jié)果顯示,,當(dāng)老化過程開始啟動(dòng),雖然萌發(fā)率仍然維持在100%的水平,,但部分的DNA和RNA已經(jīng)開始降解,,轉(zhuǎn)錄分析的數(shù)據(jù)顯示與細(xì)胞程序性死亡、氧化脅迫以及泛素蛋白相關(guān)的基因在種子失去活力以前就已經(jīng)發(fā)生了改變,。當(dāng)豌豆種子老化25天以后,,萌發(fā)率開始下降,此時(shí)谷胱甘肽的還原電勢(shì)也朝著正值方向移動(dòng)(>190mV),?;诒狙芯拷Y(jié)果,研究人員推測(cè)種子老化的過程是一個(gè)由基因控制的過程,,而且老化過程啟動(dòng)了細(xì)胞程序性死亡,,最終導(dǎo)致了種子活力的喪失。
該研究運(yùn)用先進(jìn)的分子生物學(xué)研究手段,,揭示了種子老化的分子生物學(xué)基礎(chǔ),,表明轉(zhuǎn)錄水平的重新編程是種子老化的一個(gè)關(guān)鍵組成成分,最終將導(dǎo)致程序性死亡,,種子活力的喪失,。研究成果以Transcriptome-wide mapping of pea seed ageing reveals a pivotal role for genes related to oxidative stress and programmed cell death為題于10月29日發(fā)表在植物學(xué)主流刊物Plos One上。
該研究項(xiàng)目受到了所級(jí)項(xiàng)目以及中科院“西部之光”人才項(xiàng)目的資助,。(生物谷Bioon.com)
生物谷推薦的英文摘要
PLoS One doi:10.1371/journal.pone.0078471
Transcriptome-Wide Mapping of Pea Seed Ageing Reveals a Pivotal Role for Genes Related to Oxidative Stress and Programmed Cell Death
Hongying Chen equal contributor,, Daniel Osuna equal contributor, Louise Colville mail,, Oscar Lorenzo,, Kai Graeber, Helge Küster,, Gerhard Leubner-Metzger,, Ilse Kranner
Understanding of seed ageing, which leads to viability loss during storage,, is vital for ex situ plant conservation and agriculture alike. Yet the potential for regulation at the transcriptional level has not been fully investigated. Here,, we studied the relationship between seed viability, gene expression and glutathione redox status during artificial ageing of pea (Pisum sativum) seeds. Transcriptome-wide analysis using microarrays was complemented with qRT-PCR analysis of selected genes and a multilevel analysis of the antioxidant glutathione. Partial degradation of DNA and RNA occurred from the onset of artificial ageing at 60% RH and 50°C,, and transcriptome profiling showed that the expression of genes associated with programmed cell death,, oxidative stress and protein ubiquitination were altered prior to any sign of viability loss. After 25 days of ageing viability started to decline in conjunction with progressively oxidising cellular conditions, as indicated by a shift of the glutathione redox state towards more positive values (>190 mV). The unravelling of the molecular basis of seed ageing revealed that transcriptome reprogramming is a key component of the ageing process,, which influences the progression of programmed cell death and decline in antioxidant capacity that ultimately lead to seed viability loss.