一种特殊的长寿细胞:毛竹茎秆纤维细胞

利用显微和细胞化学方法,对毛竹(Phyllostachys edulis)茎秆纤维次生壁形成过程中超微结构变化以及ATP酶、Ca2 -ATPase和酸性磷酸酶的超微细胞化学定位进行了研究.研究发现,次生壁形成早期,细胞核具有双层核膜,染色质凝聚,可见大量的线粒体、粗面内质网和高尔基体等细胞器存在于纤维细胞中;随后,双层核膜消失,细胞器将逐渐解体,多泡体开始出现在纤维细胞的细胞质;随着年龄的增加,纤维细胞壁逐渐增厚,并出现多层结构现象,而运输小泡、细胞膜、胞间连丝和凝聚的染色质将持续存在.在次生壁形成的整个过程中,ATP酶、Ca2 -ATPase和酸性磷酸酶在运输小泡、细胞膜、质膜内陷、胞间连丝和凝聚的染色质中将持续存在.结果表明,毛竹茎秆纤维细胞是一种不同于木本双子叶植物的长寿细胞,纤维原生质体中ATP酶和酸性磷酸酶的持续存在与次生壁的持续增厚密切相关.

A Special Long-Lived Cell: the Culm Fiber Cell of Phyllostachys edulis (Gramineae)

With several microscopic and cytochemical methods, the ultrastructure modification and ultracytochemical localization about some enzymes like H -ATPase. Ca2 -ATPase and acid phosphatase (APase) of fiber in Phyllostachys edulis culms during secondary wall formation were studied. Early, intact double karyotheca remained in fiber nucleus, while nuclear chromatin agglutinated. A lot of organelles such as mitochondria, rough endoplasmic reticula and Golgi bodies were observed in fiber cell. Then, double karyotheca disappeared, and the organelles disintegrated. Multivesicular bodies appeared in fiber cytoplasm. With the further development of fiber, fiber wall underwent continual thickening with aging, and polylaminate structure gradually appeared. While the agglutinated nucleus, transfer vesicles, plasma membrane and plasmodesmata still presented. During the secondary wall formation of fiber, H -ATPase, Ca2 -ATPase and APase also sustainablely remained in plasma membrane, plasma membrane invagination, plasmodesmata, transfer vesicles and agglutinated nucleus. The results demonstrated that (1) the fiber cell of P. edulis culm is a special long-lived cell, which differs from that of woody dicotyledons, and (2) the sustainable persistence of ATPase and APase in fiber protoplast is closely correlated to the continual thickening of secondary wall with ageing.