Mohajan Suman, Rubio Linda S, Gross David S
Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, LA 71130.
bioRxiv. 2025 Jan 2:2025.01.01.631024. doi: 10.1101/2025.01.01.631024.
The nuclear pore complex (NPC), a multisubunit complex located within the nuclear envelope, regulates RNA export and the import and export of proteins. Here we address the role of the NPC in driving thermal stress-induced 3D genome repositioning of () genes in yeast. We found that two nuclear basket proteins, Mlp1 and Nup2, although dispensable for NPC integrity, are required for driving genes into coalesced chromatin clusters, consistent with their strong, heat shock-dependent recruitment to gene regulatory and coding regions. gene clustering occurs predominantly within the nucleoplasm and is independent of the essential scaffold-associated proteins Nup1 and Nup145. Notably, double depletion of Mlp1 and Nup2 has little effect on the formation of Heat Shock Factor 1 (Hsf1)-containing transcriptional condensates, Hsf1 and Pol II recruitment to genes, or mRNA abundance. Our results define a 3D genome restructuring role for nuclear basket proteins extrinsic to the NPC and downstream of gene activation.
核孔复合体（NPC）是位于核膜内的多亚基复合体，负责调节RNA输出以及蛋白质的输入和输出。在此，我们探讨了NPC在驱动酵母中热应激诱导的（）基因三维基因组重定位中的作用。我们发现，两种核篮蛋白Mlp1和Nup2，虽然对于NPC的完整性并非必需，但对于将基因驱动到凝聚的染色质簇中却是必需的，这与它们在热休克依赖下被强力招募到基因调控区和编码区一致。基因聚类主要发生在核质内，且独立于必需的支架相关蛋白Nup1和Nup145。值得注意的是，Mlp1和Nup2的双重缺失对含热休克因子1（Hsf1）的转录凝聚物的形成、Hsf1和Pol II募集到基因上，或mRNA丰度几乎没有影响。我们的结果确定了核篮蛋白在NPC外部且在基因激活下游的三维基因组重组作用。
