van Wijnen A J, Bidwell J P, Fey E G, Penman S, Lian J B, Stein J L, Stein G S
Department of Cell Biology, University of Massachusetts Medical Center, Worcester 01655.
Biochemistry. 1993 Aug 24;32(33):8397-402. doi: 10.1021/bi00084a003.
The association of DNA binding proteins with the nuclear matrix may be related to a functional role of this subcellular structure in chromatin organization and gene regulation. In this study, nuclear matrix preparations from human HeLa S3 cervical carcinoma and rat ROS 17/2.8 osteosarcoma cells were assayed for the presence of DNA binding activities using consensus binding sequences of well-characterized transcription factors as probes. Competition analysis shows that each probe interacts with different nuclear matrix proteins in a sequence-specific manner and that DNA binding activities related to or identical with SP-1, ATF, CCAAT, C/EBP, OCT-1, and AP-1 are present in the nuclear matrix fraction of different cell types. Comparison of the relative abundance of these transcription factor binding activities in nuclear matrix and nonmatrix nuclear fractions suggests that the distribution between these two fractions is cell type specific, cell growth dependent, or independent of these biological parameters. These results are consistent with the postulated role of the nuclear matrix in transcriptional regulation of gene expression.
DNA结合蛋白与核基质的关联可能与这种亚细胞结构在染色质组织和基因调控中的功能作用有关。在本研究中，使用特征明确的转录因子的共有结合序列作为探针，检测了来自人宫颈癌HeLa S3细胞和大鼠骨肉瘤ROS 17/2.8细胞的核基质制剂中DNA结合活性的存在情况。竞争分析表明，每个探针以序列特异性方式与不同的核基质蛋白相互作用，并且与SP-1、ATF、CCAAT、C/EBP、OCT-1和AP-1相关或相同的DNA结合活性存在于不同细胞类型的核基质组分中。对这些转录因子结合活性在核基质和非基质核组分中的相对丰度进行比较表明，这两个组分之间的分布是细胞类型特异性的、细胞生长依赖性的或独立于这些生物学参数的。这些结果与核基质在基因表达转录调控中的假定作用一致。
