Departament de Bioquímica i Biologia Molecular, Facultat de Biociències, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain.
Mol Cell Biochem. 2011 Oct;356(1-2):233-40. doi: 10.1007/s11010-011-0970-7. Epub 2011 Jul 8.
Despite increasing progress in the study of CK2 activity in plants, a clear understanding of its functional role remains elusive. The high pleiotropic nature of the enzyme, the fact that it is absolutely necessary to maintain life, and the existence of multiple isoforms have made it difficult to obtain loss-of-function mutants with which to study the impact of CK2 depletion in the organisms. To avoid all these difficulties, we have used a dominant-negative mutant approach, by constructing a CK2α kinase-inactive subunit (CKA3mut) that was cloned downstream of an inducible promoter. Stably transformed Arabidopsis plants showed that longtime inductions of the transgene were lethal, causing growth and development arrests and ultimately resulting in plant death. However, short-time inductions were not lethal and revealed broad phenotypical changes that uncovered novel functions of CK2 in plants. The high pleiotropy of CK2 was sustained by analysis of global transcript profiles that showed a huge number of genes affected, involved in a wide variety of cellular processes.
尽管在研究 CK2 在植物中的活性方面取得了越来越多的进展，但对其功能作用仍未完全了解。该酶具有高度的多效性，是维持生命所必需的，而且存在多种同工酶，这使得获得能够研究 CK2 耗竭对生物体影响的功能丧失突变体变得困难。为了避免所有这些困难，我们使用了显性负突变体方法，构建了 CK2α 激酶无活性亚基（CKA3mut），该亚基克隆在诱导型启动子的下游。稳定转化的拟南芥植物表明，长时间诱导转基因是致命的，导致生长和发育停滞，最终导致植物死亡。然而，短时间诱导不会导致死亡，并揭示了广泛的表型变化，揭示了 CK2 在植物中的新功能。通过分析显示受影响的基因数量巨大，涉及多种细胞过程的全转录谱分析，维持了 CK2 的高度多效性。
