Transcription and RNA processing factors play complex roles in DT40 cells.

Functional analysis of factors involved in transcription and RNA processing is difficult in vivo because of the importance of these processes to maintain cell viability. The ability to perform conditional knockouts and to generate stable transfectants in DT40 cells has facilitated the study of general transcription factors such as TATA binding proteins, essential splicing factors such as ASF/SF2 and crucial polyadenylation factors such as CstF64, as well as a number of more specific regulators of gene expression. The complexity of transcriptional regulation and the coupled mechanisms of RNA processing lead to the delineation of sometimes surprising roles for these factors in DT40 cells. Specifically, many of the components of the RNA transcriptional/processing machinery function to regulate cell proliferation in some manner, causing cell cycle abnormalities or cell death when cellular expression of any one of these components are altered. Additionally, only one of the factors described affected RNA synthesis in a global manner.