玉米异交不亲和基因Ga1-S的蛋白质组分析

Proteomic Analysis of Maize Cross Incompatibility Gene Ga1-S

为了研究玉米异交不亲和的蛋白表达机制,以玉米(Zea mays L.)异交不亲和基因Gal-S的一对近等基因系W22(GG)与w22(gg)为材料,组配自交(GG×GG)、正交(gg×GG)与反交(GG×gg)3个组合。首先采用荧光显微技术,观察比较了3个组合中花粉管在花丝中的生长过程;其次采用IEF/SDS-PAGE双向凝胶电泳与基质辅助激光解吸电离飞行时间质谱(MALDI-TOF-MS)技术,比较研究了授粉后10h自交与反交母本W22(GG)花丝蛋白质组的特异表达差异。结果表明,授粉后10h,自交与正交花粉管伸长可达花丝基部,而反交花丝基部未观察到花粉管;自交与反交母本W22(GG)花丝蛋白质组共检测到25个差异蛋白质点,其中15个在自交中特异表达,10个在反交中特异表达。通过MALDI-TOF-MS质谱测序和MASCOT序列分析,注释了12个蛋白质点,其中自交中特异表达的蛋白质点11、12、14和异交中特异表达的蛋白质点18、22、24可能与玉米异交不亲和密切相关。

The objective of this paper was to study the cross incompatibility gene Ga1-S in maize through proteomic approach.Near isogonic lines of Ga1-S gene,W22（GG） and w22（gg）,were used to make the crosses of GG×GG,gg×GG,and GG×gg.First,we observed the growth process of pollen tubes grown into silks in three crosses by fluorescence microscopy;second,total silk proteins were extracted from silks of the W22（GG） at 10 h after pollination.Total proteins were extracted by TCA/Acetone,separated by two-dimensional gel electrophoresis（2-DE） and analyzed through MALDI-TOF-MS mass spectrometry.The results indicated that pollen tube could not grow into silks base in the cross of GG×gg,but could reach the silk base in the other two crosses.In the silk proteomes of GG×GG and GG×gg,there were 25 differentially expressed proteins,including 15 specifically expressed in GG×GG,and 10 specifically expressed in GG×gg.Twelve of them were annotated in various databases by MALDI-TOF-MS and MASCOT analyses.Proteins 11,12,14,18,22,and 24 presumably play important roles in the maize cross incompatibility.