Meimoun Patrice, Gousset-Dupont Aurélie, Lebouteiller Bénédicte, Ambard-Bretteville Françoise, Besin Evelyne, Lelarge Caroline, Mauve Caroline, Hodges Michael, Vidal Jean
Institut de Biotechnologie des Plantes, Centre National de la Recherche Scientifique Unité Mixte de Recherche 8618, Université Paris-Sud 11, Orsay Cedex, France.
FEBS Lett. 2009 May 19;583(10):1649-52. doi: 10.1016/j.febslet.2009.04.030. Epub 2009 May 4.
Two phosphoenolpyruvate carboxylase (PEPC) kinase genes (PPCk1 and PPCk2) are present in the Arabidopsis genome; only PPCk1 is expressed in rosette leaves. Homozygous lines of two independent PPCk1 T-DNA-insertional mutants showed very little (dln1), or no (csi8) light-induced PEPC phosphorylation and a clear retard in growth under our greenhouse conditions. A mass-spectrometry-based analysis revealed significant changes in metabolite profiles. However, the anaplerotic pathway initiated by PEPC was only moderately altered. These data establish the PPCk1 gene product as responsible for leaf PEPC phosphorylation in planta and show that the absence of PEPC phosphorylation has pleiotropic consequences on plant metabolism.
拟南芥基因组中存在两个磷酸烯醇式丙酮酸羧化酶（PEPC）激酶基因（PPCk1和PPCk2）；只有PPCk1在莲座叶中表达。两个独立的PPCk1 T-DNA插入突变体的纯合系在我们的温室条件下显示出极少（dln1）或没有（csi8）光诱导的PEPC磷酸化，并且生长明显迟缓。基于质谱的分析揭示了代谢物谱的显著变化。然而，由PEPC启动的回补途径仅发生了适度改变。这些数据表明PPCk1基因产物负责植物叶片中的PEPC磷酸化，并表明PEPC磷酸化的缺失对植物代谢具有多效性影响。
