水稻胚乳发育中ATP酶的超微细胞化学定位和功能分析

 应用磷酸铅沉淀技术 ,对水稻 (OryzasativaL .)胚乳发育中ATP酶进行了超微细胞化学定位研究。结果表明 ,在胚乳游离核期和细胞化期 ,胚囊壁、细胞核和质膜上有ATP酶活性分布。在生长分化期的早期 ,ATP酶主要定位于胚乳细胞质膜上。在灌浆高峰期 ,糊粉层细胞的质膜、胞间隙和胞间连丝上有显著的ATP酶活性 ;亚糊粉层间的质膜上ATP酶活性较高 ;淀粉胚乳细胞的质膜、衰退的细胞核上有ATP酶活性分布 ;胚乳细胞的液泡、蛋白体周围分布有ATP酶。综合观察结果 ,认为ATP酶主要参与胚乳对物质的吸收和贮藏蛋白质的合成。

Ultracytochemical Localization and Functional Analysis of ATPase During the Endosperm Development in Oryza sativa L.

Ultracytochemical localization of ATPase during development of rice endosperm was performed using a lead phosphate precipitation technique. The results indicated that, at the coenocyte and cellularization stages, active ATPase was mainly distributed in an embryo sac wall, nucleus, and plasma membrane. At the early stage of development and differentiation, active ATPase was observed in the plasma membrane. At the grain filling stage, ATPase was highly active in the plasma membrane, intercellular space, and plasmodesmata in aleurone, moderate active on the plasma membrane in subaleurone. In starchy endosperm, ATPase was localized in the plasma membrane and degenerated nucleus. ATPase activity appeared around vacuole and protein body in endosperm cell. The relationships between the ultracytochemical localization of ATPase and its function in the developing rice endosperm were discussed. It is concluded that ATPase is involved in the process of nutrition absorption and protein synthesis.