Pathobiology Area Graduate Program, Christopher S. Bond Life Sciences Center, School of Medicine, University of Missouri-Columbia, Columbia, MO 65211, USA.
Christopher S. Bond Life Sciences Center, Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri-Columbia, Columbia, MO 65211, USA.
Viruses. 2020 Nov 30;12(12):1368. doi: 10.3390/v12121368.
Specific chromatin immunoprecipitation of salt-fractionated infected cell extracts has demonstrated that the CCCTC-binding factor (CTCF), a highly conserved, 11-zinc-finger DNA-binding protein with known roles in cellular and viral genome organization and gene expression, specifically binds the genome of Minute Virus of Mice (MVM). Mutations that diminish binding of CTCF to MVM affect processing of the P4-generated pre-mRNAs. These RNAs are spliced less efficiently to generate the R1 mRNA, and definition of the NS2-specific exon upstream of the small intron is reduced, leading to relatively less R2 and the generation of a novel exon-skipped product. These results suggest a model in which CTCF is required for proper engagement of the spliceosome at the MVM small intron and for the first steps of processing of the P4-generated pre-mRNA.
盐析感染细胞提取物的特定染色质免疫沉淀已证明，CCCTC 结合因子（CTCF）是一种高度保守的、具有 11 个锌指的 DNA 结合蛋白，已知在细胞和病毒基因组组织和基因表达中具有作用，特异性结合小鼠微小病毒（MVM）的基因组。降低 CTCF 与 MVM 结合的突变会影响 P4 产生的前体 mRNA 的加工。这些 RNA 的剪接效率降低，从而生成 R1 mRNA，并且小内含子上游的 NS2 特异性外显子的定义减少，导致相对较少的 R2 和产生新的外显子跳过产物。这些结果表明，CTCF 是正确参与 MVM 小内含子中的剪接体所必需的，并且是 P4 产生的前体 mRNA 加工的第一步所必需的。
