Departament de Bioquímica i Biologia Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain.
Plant Signal Behav. 2011 Aug;6(8):1127-31. doi: 10.4161/psb.6.8.16363. Epub 2011 Aug 1.
The enzyme HMG-CoA reductase (HMGR) has a key regulatory role in the mevalonate pathway for isoprenoid biosynthesis, critical not only for normal plant development, but also for the adaptation to demanding environmental conditions. Consistent with this notion, plant HMGR is modulated by many diverse endogenous signals and external stimuli. Protein phosphatase 2A (PP2A) is involved in auxin, abscisic acid, ethylene and brassinosteroid signaling and now emerges as a positive and negative multilevel regulator of plant HMGR, both during normal growth and in response to a variety of stress conditions. The interaction with HMGR is mediated by B" regulatory subunits of PP2A, which are also calcium binding proteins. The new discoveries uncover the potential of PP2A to integrate developmental and calcium-mediated environmental signals in the control of plant HMGR.
羟甲基戊二酰辅酶 A 还原酶（HMGR）在异戊烯基生物合成的甲羟戊酸途径中具有关键的调节作用，这不仅对植物的正常发育至关重要，而且对适应苛刻的环境条件也至关重要。与这一观点一致的是，植物 HMGR 受到许多不同的内源性信号和外部刺激的调节。蛋白磷酸酶 2A（PP2A）参与生长素、脱落酸、乙烯和油菜素内酯信号转导，现在作为植物 HMGR 的正、负多级调节剂出现，无论是在正常生长过程中，还是在应对各种胁迫条件下。与 HMGR 的相互作用是由 PP2A 的 B"调节亚基介导的，B"调节亚基也是钙结合蛋白。这些新发现揭示了 PP2A 在控制植物 HMGR 方面整合发育和钙介导的环境信号的潜力。
