The interaction between chromatin and the nuclear lamina (NL) is intrinsically important to the establishment of three-dimensional chromatin architecture and spatiotemporal regulation of gene expression. However, critical regulators involved in this process are poorly understood in plants. Here, we report that Arabidopsis PNET2 and its two homologs are bona fide inner nuclear membrane proteins and integral components of the NL. PNET2s physically interact with the plant nucleoskeleton and engage nucleosome-enriched chromatin at the nuclear periphery. Loss of all three PNET2s leads to severely disrupted growth and development, concomitant activation of abiotic and biotic stress responses, and ultimate lethality in Arabidopsis. The pent2 triple mutant also displays drastic transcriptome changes accompanied by a globally altered chromatin architecture revealed by HiC analysis. Our study identified PNET2 as an inner nuclear membrane (INM) component of the NL, which associates with chromatin and play a critical role in orchestrating gene expression and chromatin organization in plants.

染色质和核层 (NL) 之间的相互作用对于建立三维染色质结构和基因表达的时空调控具有内在的重要性。然而，在植物中对这一过程所涉及的关键调节因子知之甚少。在这里，我们报告拟南芥PNET2 及其两个同源物是真正的内核膜蛋白和 NL 的组成部分。PNET2s 与植物核骨架发生物理相互作用，并在核外围与富含核小体的染色质结合。所有三个 PNET2 的缺失都会导致生长和发育严重中断，同时激活非生物和生物应激反应，并最终导致拟南芥死亡。pent2 _三重突变体还显示出剧烈的转录组变化，并伴随着 HiC 分析揭示的全局改变的染色质结构。我们的研究将 PNET2 确定为 NL 的内核膜 (INM) 成分，它与染色质相关，并在协调植物中的基因表达和染色质组织中发挥关键作用。