向日葵胚珠中ATP酶活性的超微细胞化学定位  

THE ULTRACYTOCHEMICAL LOCALIZATION OF ATPASE ACTIVITY IN THE OVULES OF SUNFLOWER

作　　者：何才平 杨弘远[1] 

机构地区：[1]武汉大学生物系

出　　处：《Acta Botanica Sinica》1991年第8期574-580,共7页Acta Botanica Sinica（植物学报：英文版）

基　　金：高等学校博士点专项研究基金资助项目

摘　　要：用细胞化学方法,对向日葵(Helianthusannuus L.)开花前后胚珠中的ATP酶进行了超微细胞化学定位。在卵器中,仅助细胞丝状器上有酶活性;中央细胞质膜和壁内有酶活性;反足细胞的核、质和壁内均仅有少量酶活性,但质膜特别是合点端壁内突的部位酶活性较强。在珠被绒毡层细胞中,ATP酶主要定位在核和质膜上。珠被绒毡层与胚囊壁外的角质层之间有一间隙层,大量ATP酶分布其间,并通过角质层的间断处与胚囊壁内的酶连成一片。间隙层在中央细胞壁内突外侧的部位,则有大量具酶活反应的小泡和其它结构物质集聚。ATP酶的分布特性说明:整个胚囊表面均能通过质外体途径直接从角质层外的珠被组织中吸收营养,其中中央细胞壁内突是主要吸收部位。The ultracytochemical localization of ATPase activity was determined employing the method of lead precipitation in the ovules of sunflower (Helianthus annuus L.). No ATPase activity is observed in the egg and synergids except some at the filiform apparatus. Much ATPase activity is localized on the plasma membrane and wall of the central cell. In the antipodal cells, ATPase activity is also found on the plasma membranes, but only a little in their walls.In the integumentary tapetum, besides the plasma membranes, most of the nuclei are rich in ATPase. Between the integumentary tapetum and uncontinuous cuticle surrounding the embryo sac, there is a gap where a lot of ATPase are found. These ATPases are continuously linked with those in the central cell wall throuth the intervals of the cuticle. At the sites of the wall ingrowths of the central cell, abundant vesicles and other structures with high ATPase activity aggregate noticeably in the gap region.According to the ATPase distribution in the ovules, we propose that the whole surface of embryo sac functions in absorbing nutrients direct,ly from the apoplast outside the cuticle, especially via the wall-membrane apparatus of the central cell.

关 键 词：向日葵 胚珠 三磷酸腺苷酶 定位 

分 类 号：S565.501[农业科学—作物学]