Dunoyer Patrice, Pfeffer Sébastien, Fritsch Christiane, Hemmer Odile, Voinnet Olivier, Richards K E
Institut de Biologie Moléculaire des Plantes du CNRS et de l'Université Louis Pasteur, 12 Rue du Général Zimmer, 67084 Strasbourg, France.
Plant J. 2002 Mar;29(5):555-67. doi: 10.1046/j.0960-7412.2001.01242.x.
In plants, post-transcriptional gene silencing (PTGS) is part of a defence mechanism against virus infection. Several plant viruses have been shown to encode proteins which can counteract PTGS. In this paper it is demonstrated that P15 of peanut clump pecluvirus (PCV) has anti-PTGS activity. P15 is a small cysteine-rich protein with no sequence similarity to previously described PTGS-suppressor proteins which has several novel properties. It possesses four C-terminal proximal heptad repeats that can potentially mediate a coiled-coil interaction and is targeted to peroxisomes via a C-terminal SKL motif. The coiled-coil sequence is necessary for the anti-PTGS activity of P15, but the peroxisomal localization signal is not, although it is required for efficient intercellular movement of the virus.
在植物中，转录后基因沉默（PTGS）是抵御病毒感染的防御机制的一部分。已有研究表明，几种植物病毒编码的蛋白质能够对抗PTGS。本文证明花生丛簇病毒（PCV）的P15具有抗PTGS活性。P15是一种富含半胱氨酸的小蛋白，与先前描述的PTGS抑制蛋白没有序列相似性，具有几个新特性。它具有四个靠近C端的七肽重复序列，可能介导卷曲螺旋相互作用，并通过C端的SKL基序定位于过氧化物酶体。卷曲螺旋序列对于P15的抗PTGS活性是必需的，但过氧化物酶体定位信号不是必需的，尽管它是病毒有效细胞间移动所必需的。
