应用基因芯片分析红蚰麦白粉菌胁迫条件下的基因表达谱

小麦农家品种红蚰麦携带1对显性抗白粉病新基因，暂命名为Pmhym。为了深入了解该品种抗病的分子机制，用豫麦13/红蚰麦的F₃代纯合抗病株系构建抗池，并对白粉菌接种后24 h的基因表达谱，采用Affymetrix小麦基因芯片进行分析，以白粉菌接种0 h为对照。在61 127基因微矩阵点中，有效差异表达Ratio值≥2或≤0.5的基因共5 282个，其中上调基因2 553个，下调2 729个。对上调序列的分类表明，功能明确的序列中39.81%与抗病/防御相关；下调表达基因中以能量代谢和抗病/防御相关基因比例最高，分别占26.71%和19.65%。上调表达在8倍以上的序列中81个的功能已知，其中包括病程相关基因、防卫反应基因、生成或清除活性氧的基因，以及抗病信号转导基因等。选取上调和下调表达8倍以上的共13个探针序列进行实时定量PCR验证，表明基因芯片数据具有良好的重复性。

Expression Profile of Landrace Hongyoumai Infected by Blumeria graminis f. sp.tritici Using Gene Microarray

Wheat landrace Hongyoumai carries one dominant resistance gene for powdery mildew (Blumeria graminis), tentatively designated Pmhym. To further elucidate molecular mechanism of the resistance to powdery mildew in Hongyoumai, a resistant pool was constructed with four homogenous resistant lines from the F₃ generation of Yumai 13/Hongyoumai. The wheat seedlings were inoculated with single spore isolates of B. graminis f. sp. tritici, and at 0 and 24 h after inoculation the gene expression profile was analyzed using Affymetrix wheat microarray. There were approximately 5 282 expressed genes (with Log ratio ≥ 2 or ≤ 0.5) among total 61 127 genes set in the microarray plate, including 2 553 up-regulated and 2729 down-regulated genes or expressed sequence tags (ESTs). In the up-regulated ESTs whose functions have been known, 39.81% were disease/defense genes. In the down-regulated ESTs, energy genes and disease/defense genes accounted for 26.71% and 19.65%, respectively. A total of 81 ESTs were up-regulated more than eight times, in which most were related to disease resistance, such as pathogenesis-related protein, defense genes, genes producing or eliminating reactive oxygen species, and genes involved in signal transduction. Quantitative RT-PCR (qRT-PCR) was carried out with 13 probe sets up-regulated and down-regulated more than eight times which validated a good reproducibility of microarray analysis.