Link Manuela, Rausch Thomas, Greiner Steffen
Heidelberg Institute of Plant Sciences (HIP), Im Neuenheimer Feld 360, D-69120 Heidelberg, Germany.
FEBS Lett. 2004 Aug 27;573(1-3):105-9. doi: 10.1016/j.febslet.2004.07.062.
Plant cell wall (CWI) and vacuolar invertases (VI) play important roles in carbohydrate metabolism, stress responses and sugar signaling. Addressing the regulation of invertase activities by inhibitor proteins (C/VIF, cell wall/vacuolar inhibitor of fructosidase), we have identified two C/VIFs from Arabidopsis thaliana. AtC/VIF1 showed specific inhibition of VI activity, whereas AtC/VIF2 inhibited both, CWI and VI. Expression analysis revealed that expression of AtC/VIF1 was restricted to specific organs, AtC/VIF2, however, was weakly expressed throughout plant development. Promoter::GUS transformants confirmed pronounced differences of tissue/cell type-specific expression between both isoforms. Growth of an AtC/VIF1 T-DNA KO mutant was unaffected, but VI activity and hexose content were slightly increased.
植物细胞壁转化酶（CWI）和液泡转化酶（VI）在碳水化合物代谢、应激反应和糖信号传导中发挥着重要作用。在研究抑制剂蛋白（C/VIF，细胞壁/液泡果糖苷酶抑制剂）对转化酶活性的调控时，我们从拟南芥中鉴定出了两种C/VIF。AtC/VIF1对VI活性表现出特异性抑制，而AtC/VIF2则同时抑制CWI和VI。表达分析表明，AtC/VIF1的表达局限于特定器官，然而，AtC/VIF2在植物发育过程中均有微弱表达。启动子::GUS转化体证实了这两种同工型在组织/细胞类型特异性表达上存在明显差异。AtC/VIF1 T-DNA敲除突变体的生长未受影响，但VI活性和己糖含量略有增加。
