Transfer cell induction in cotyledons of Vicia faba L.
Transfer cell induction in cotyledons of Vicia faba L.
复制标题
DOI：
10.1007/bf01280734
复制
发表时间：
1997-01-01
期刊：
影响因子：
2.9
通讯作者：
Sutton, EG
中科院分区：
文献类型：
--
作者：
Offler, CE;Liet, E;Sutton, EG
在蚕豆种子饱满前，子叶的远轴面分化出一个由表皮细胞和亚表皮细胞组成的表皮转移细胞复合体。在此期间的复杂的体内分化，种子质外液的主要糖的变化从己糖，葡萄糖和果糖，蔗糖。在转移细胞复合体分化之前从种子中取出子叶，并在琼脂基培养基上在黑暗中培养6天，使子叶的远轴面与含有100 mM己糖（等摩尔浓度的葡萄糖和果糖）或100 mM蔗糖的培养基接触。在两种培养基上，子叶生长速率在整个培养期间保持在等于或高于体内生长的子叶的发育年龄。当子叶培养在含有葡萄糖和果糖的培养基上，表皮细胞的ab-and adaxial表面发展壁向内生长的外周壁和他们的细胞质变得致密，泡状，和丰富的线粒体。广泛的向内生长沉积也发生在表皮下细胞和几排下面的储存细胞的壁上，它们覆盖细胞间隙。后者向内生长的发展是明显的子叶表面上，但延伸到更多的底层细胞层上的子叶的索状端的远轴面。在体内生长的子叶中，这种向内生长发育仅限于远轴面的表皮下细胞。向内生长的形态与体内生长的子叶的转移细胞的形态相当。在含有葡萄糖和果糖的培养基上观察到的诱导，与蔗糖作为唯一的糖源培养的子叶表现出没有向内生长的沉积或小的壁向内生长在一些远轴表皮细胞。虽然潜在的糖信号机制是未知的，这种培养系统提供了一个令人兴奋的机会，探索转移细胞发育的分子生物学。
Immediately prior to seed fill, a dermal transfer cell complex, comprised of epidermal and subepidermal cells, differentiates on the abaxial surface of the cotyledons in seed of Vicia faba. Over the period of differentiation of this complex in vivo, the principal sugars of the seed apoplasmic sap change from hexoses, glucose and fructose, to sucrose. Cotyledons were removed from seeds before differentiation of the transfer cell complex and cultured for 6 days on an agar-based medium in the dark with their abaxial surface in contact with a medium containing either 100 mM hexoses (glucose and fructose in equimolar concentrations) or 100 mM sucrose. On both media, cotyledon growth rate was maintained throughout the culture period at, or above, that of in vivo grown cotyledons of equivalent developmental age. When cotyledons were cultured on a medium containing glucose and fructose, epidermal cells of both the ab-and adaxial surfaces developed wall ingrowths on their outer periclinal walls and their cytoplasm became dense, vesicular, and rich in mitochondria. Extensive ingrowth deposition also occurred on walls of the subepidermal cells and several rows of underlying storage cells where they abutted intercellular spaces. This latter ingrowth development was apparent on both cotyledon surfaces, but extended into more of the underlying cell layers on the abaxial surface at the funicular end of the cotyledon. In in vivo grown cotyledons, such ingrowth development is restricted to the subepidermal cells of the abaxial surface. Ingrowth morphology was commensurate with that of transfer cells of in vivo grown cotyledons. In contrast to the observed induction on a medium containing glucose and fructose, cotyledons cultured with sucrose as the sole sugar source exhibited no ingrowth deposition or small wall ingrowths in some abaxial epidermal cells. While the potential sugar signalling mechanism is unknown, this culture system offers an exciting opportunity to explore the molecular biology of transfer cell development.