Rylott EL, Metzlaff K, Rawsthorne S
John Innes Centre, Norwich Research Park, Colney, Norwich NR4 7UH, United Kingdom.
Plant Physiol. 1998 Dec;118(4):1277-84. doi: 10.1104/pp.118.4.1277.
Cellular anatomy and expression of glycine decarboxylase (GDC) protein were studied during leaf development of the C3-C4 intermediate species Moricandia arvensis. Leaf anatomy was initially C3-like and the number and profile area of mitochondria in the bundle-sheath cells were the same as those in adjacent mesophyll cells. Between a leaf length of 6 and 12 mm there was a bundle-sheath-specific, 4-fold increase in the number of mitochondrial profiles, followed by a doubling of their individual profile areas as the leaves expanded further. Subunits of GDC were present in whole-leaf extracts before the anatomical development of bundle-sheath cells. Whereas the GDC H-protein content of leaves increased steadily throughout development, the increase in GDC P-protein was synchronous with the development of mitochondria in the bundle sheath. The P-protein was confined to bundle-sheath mitochondria throughout leaf development, and its content in individual mitochondria increased before the anatomical development of the bundle sheath. Anatomical and biochemical attributes of the C3-C4 character were present in the cotyledons and sepals but not in other photosynthetic organs/tissues. In leaves and cotyledons that developed in the dark, the expression of the P-protein and the organellar development were reduced but the bundle-sheath cell specificity was retained.
在C3 - C4中间型物种田野滨藜叶片发育过程中，对甘氨酸脱羧酶（GDC）蛋白的细胞解剖结构和表达进行了研究。叶片解剖结构最初类似C3植物，维管束鞘细胞中线粒体的数量和轮廓面积与相邻叶肉细胞中的相同。在叶片长度为6至12毫米之间，线粒体轮廓数量出现了维管束鞘特异性的4倍增加，随着叶片进一步扩展，其单个轮廓面积又增加了一倍。在维管束鞘细胞进行解剖发育之前，GDC亚基就已存在于全叶提取物中。尽管叶片的GDC H蛋白含量在整个发育过程中稳步增加，但GDC P蛋白的增加与维管束鞘中线粒体的发育同步。在叶片整个发育过程中，P蛋白都局限于维管束鞘线粒体中，并且其在单个线粒体中的含量在维管束鞘进行解剖发育之前就增加了。C3 - C4特征的解剖学和生化特性存在于子叶和萼片中，但不存在于其他光合器官/组织中。在黑暗中发育的叶片和子叶中，P蛋白的表达和细胞器发育减少，但维管束鞘细胞特异性得以保留。
