Pawar Vidya, Poulet Axel, Détourné Gwénaëlle, Tatout Christophe, Vanrobays Emmanuel, Evans David E, Graumann Katja
Department of Biological and Medical Sciences, Faculty of Health and Life Sciences, Oxford Brookes University, Oxford, OX3 0BP, UK UMR CNRS 6293 INSERM U 1103 Clermont Université, GReD, Avenue des Landais 63171 Aubière Cedex, France.
UMR CNRS 6293 INSERM U 1103 Clermont Université, GReD, Avenue des Landais 63171 Aubière Cedex, France.
J Exp Bot. 2016 Oct;67(19):5699-5710. doi: 10.1093/jxb/erw332. Epub 2016 Sep 14.
This paper describes the characterisation of a new family of higher plant nuclear envelope-associated proteins (NEAPs) that interact with other proteins of the nuclear envelope. In the model plant Arabidopsis thaliana, the family consists of three genes expressed ubiquitously (AtNEAP1-3) and a pseudogene (AtNEAP4). NEAPs consist of extensive coiled-coil domains, followed by a nuclear localisation signal and a C-terminal predicted transmembrane domain. Domain deletion mutants confirm the presence of a functional nuclear localisation signal and transmembrane domain. AtNEAP proteins localise to the nuclear periphery as part of stable protein complexes, are able to form homo- and heteromers, and interact with the SUN domain proteins AtSUN1 and AtSUN2, involved in the linker of nucleoskeleton and cytoskeleton (LINC) complex. An A. thaliana cDNA library screen identified a putative transcription factor called AtbZIP18 as a novel interactor of AtNEAP1, which suggest a connection between NEAP and chromatin. An Atneap1 Atneap3 double-knockout mutant showed reduced root growth, and altered nuclear morphology and chromatin structure. Thus AtNEAPs are suggested as inner nuclear membrane-anchored coiled-coil proteins with roles in maintaining nuclear morphology and chromatin structure.
本文描述了一个与核膜其他蛋白相互作用的高等植物核膜相关蛋白（NEAPs）新家族的特征。在模式植物拟南芥中，该家族由三个普遍表达的基因（AtNEAP1 - 3）和一个假基因（AtNEAP4）组成。NEAPs由广泛的卷曲螺旋结构域组成，随后是一个核定位信号和一个C端预测的跨膜结构域。结构域缺失突变体证实了功能性核定位信号和跨膜结构域的存在。AtNEAP蛋白作为稳定蛋白复合物的一部分定位于核周，能够形成同聚体和异聚体，并与参与核骨架与细胞骨架连接复合体（LINC复合体）的SUN结构域蛋白AtSUN1和AtSUN2相互作用。对拟南芥cDNA文库的筛选鉴定出一种名为AtbZIP18的假定转录因子作为AtNEAP1的新型相互作用蛋白，这表明NEAP与染色质之间存在联系。Atneap1 Atneap3双敲除突变体显示出根生长减少，以及核形态和染色质结构改变。因此，AtNEAPs被认为是锚定在内核膜上的卷曲螺旋蛋白，在维持核形态和染色质结构方面发挥作用。
