以离体实验系统探讨钙和凝集素在植物双受精中的作用

Several lectins conjugated with fluorescein isothiocyanate (FITC) were used as probes to investigate the distribution of their receptors on sexual cells of Zea mays, Nicotiana tobacum and Torenia fourieri toward understanding its possible role in fertilization.. With the aid of image analysis it was found that the same lectin receptor differentially distributed on different sexual cells and the same sexual cell showed distinct localization of different lectin receptors in all species used. In maize it was found that Con A receptor strongly labeled egg and central cells, but weakly labeled sperm; WAG receptor labeled egg, not sperm cells; PHA receptor did not label both egg and sperm cells before fertilization. However, Fluorescence signals of two sperms from the same pollen grain showed no difference in the location of the lectin receptors. In Torenia a polar distribution of the receptor in embryo sac was observed and the dynamic of Con A receptor accumulation in embryo sac temporally companies the pollen tube penetration and fertilization process. The isolation procedure did not notably modify the surface character of the female cells, indicated by the comparison of both in vivo and in vitro labeling in T. fourieri. In maize comparative studies revealed that PHA receptor detected on egg cell membranes only after fertilization. WAG's binding to egg cells was enhanced after fertilization. These results demonstrate the occurrence of fertilization-induced changes in glycoprotein composition of gamet membranes. The results also showed that calcium was necessary for WAG and PHA binding to their receptors and obviously enhanced Con A labeling in all species labeled, indicating its critical role in lectin-receptor binding.

以离体受精操作系统探讨钙和凝集素在高等植物配子识别与融合过程中的作用。测试雌雄配子对外源钙不同处理形式的反应，寻找钙诱导离体受精的关键作用模式；求证配子细胞膜凝集素受体特异类型及分布。探讨凝集素在配子识别中的可能作用。结晶在为了解双受精机制及其与运动和低等植物配子融合的共性提供有价值的新资料并建立更新自然的体外融合系统。