O'Keefe R T, Mayeda A, Sadowski C L, Krainer A R, Spector D L
Cold Spring Harbor Laboratory, New York 11724.
J Cell Biol. 1994 Feb;124(3):249-60. doi: 10.1083/jcb.124.3.249.
We have examined the functional significance of the organization of pre-mRNA splicing factors in a speckled distribution in the mammalian cell nucleus. Upon microinjection into living cells of oligonucleotides or antibodies that inhibit pre-mRNA splicing in vitro, we observed major changes in the organization of splicing factors in vivo. Interchromatin granule clusters became uniform in shape, decreased in number, and increased in both size and content of splicing factors, as measured by immunofluorescence. These changes were transient and the organization of splicing factors returned to their normal distribution by 24 h following microinjection. Microinjection of these oligonucleotides or antibodies also resulted in a reduction of transcription in vivo, but the oligonucleotides did not inhibit transcription in vitro. Control oligonucleotides did not disrupt splicing or transcription in vivo. We propose that the reorganization of splicing factors we observed is the result of the inhibition of splicing in vivo.
我们研究了哺乳动物细胞核中以斑点状分布的前体mRNA剪接因子组织的功能意义。将在体外抑制前体mRNA剪接的寡核苷酸或抗体显微注射到活细胞中后，我们在体内观察到剪接因子组织的主要变化。通过免疫荧光测量，染色质间颗粒簇形状变得均匀，数量减少，并且在大小和剪接因子含量上均增加。这些变化是短暂的，显微注射后24小时内剪接因子的组织恢复到正常分布。这些寡核苷酸或抗体的显微注射还导致体内转录减少，但这些寡核苷酸在体外不抑制转录。对照寡核苷酸在体内不破坏剪接或转录。我们提出，我们观察到的剪接因子的重新组织是体内剪接受到抑制的结果。
