Institut de Biologie Moléculaire des Plantes du CNRS, University of Strasbourg, Strasbourg, Alsace, France.
Plant Signal Behav. 2011 May;6(5):748-50. doi: 10.4161/psb.6.5.15148. Epub 2011 May 1.
The novel pentatricopeptide repeat protein PNM1 has recently been shown to be dual localized to the nucleus and mitochondria. In the nucleus it binds proteins involved in regulating gene expression, especially a TCP transcription factor. This class of proteins was recently shown to control the expression of nuclear genes encoding mitochondrial proteins that contain cis-acting "site II" regulatory elements in their promoter regions. The analysis of mutant plants showed that some genes with site II elements have increased expression levels when PNM1 is not present in the nucleus. This suggests that PNM1 might act as a negative regulator for the expression of an unknown number of genes with site II elements. Altogether, PNM1 might act as a nuclear regulator and / or could be a retrograde messenger molecule from mitochondria to the nucleus for the fine-tuning of nuclear gene expression required for mitochondrial biogenesis.
最近的研究表明，新型五肽重复蛋白 PNM1 双重定位于细胞核和线粒体。在细胞核中，它与参与调节基因表达的蛋白质结合，特别是 TCP 转录因子。最近的研究表明，这类蛋白质控制着编码线粒体蛋白质的核基因的表达，这些蛋白质在其启动子区域含有顺式作用的“位点 II”调节元件。对突变体植物的分析表明，当 PNM1 不存在于细胞核中时，一些具有位点 II 元件的基因的表达水平会增加。这表明 PNM1 可能作为一个未知数量的具有位点 II 元件的基因表达的负调节剂。总的来说，PNM1 可能作为一个核调节剂，或者可以作为从线粒体到细胞核的逆行信使分子，用于微调线粒体生物发生所需的核基因表达。
