Chiquet-Ehrismann R, Matsuoka Y, Hofer U, Spring J, Bernasconi C, Chiquet M
Friedrich Miescher Institute, Basel, Switzerland.
Cell Regul. 1991 Nov;2(11):927-38. doi: 10.1091/mbc.2.11.927.
In the chicken, three tenascin variants have been characterized that are generated by alternative splicing of 3 of its 11 fibronectin type III repeats. Using monoclonal antibodies that react with common regions versus extra repeats of tenascin, we could distinguish and separate tenascin variants and investigate their interaction with fibronectin using multiple experimental procedures. Interestingly, in all assays used the smallest tenascin variant bound more strongly to fibronectin than the larger ones. These biochemical data were paralleled by the observation that in chick embryo fibroblast cultures only the smallest form of tenascin could be detected in the fibronectin-rich extracellular matrix network laid down by the cells. Furthermore, each tissue present in adult chicken gizzard contained a distinct set of tenascin variants. Those tissues particularly rich in extracellular matrix, such as the tendon, contained the smallest tenascin only. Intermediate-sized tenascin was present in smooth muscle, whereas the largest form was exclusively detectable underneath the epithelial lining of the villi. Thus it appears that cell type-specific forms of tenascin exist that are appropriate for the functional requirements of the respective extracellular matrices.
在鸡中，已鉴定出三种腱生蛋白变体，它们是由其11个III型纤连蛋白重复序列中的3个通过可变剪接产生的。使用与腱生蛋白的共同区域和额外重复序列反应的单克隆抗体，我们能够区分和分离腱生蛋白变体，并使用多种实验方法研究它们与纤连蛋白的相互作用。有趣的是，在所有使用的测定中，最小的腱生蛋白变体比更大的变体与纤连蛋白的结合更强。这些生化数据与以下观察结果一致：在鸡胚成纤维细胞培养物中，在细胞分泌的富含纤连蛋白的细胞外基质网络中只能检测到最小形式的腱生蛋白。此外，成年鸡砂囊中存在的每个组织都含有一组不同的腱生蛋白变体。那些细胞外基质特别丰富的组织，如肌腱，只含有最小的腱生蛋白。中等大小的腱生蛋白存在于平滑肌中，而最大形式的腱生蛋白仅在绒毛上皮衬里下方可检测到。因此，似乎存在适合各自细胞外基质功能需求的细胞类型特异性腱生蛋白形式。
