Wei Shao, Zhan Ding, Zeng-Zhang Zheng, Ji-Jia Shen, Yu-Xian Shen, Jia Pu, Yu-Jie Fan, Charles C Query, and Yong-Zhen Xu
Nucleic Acids Res (2020), gkaa311, doi:10.1093/nar/gkaa311
Understanding the coupling between steps in gene expression is currently one of the grand challenges in biology. This paper provides strong evidence that the ATP-dependence of pre-spliceosome formation (which is dispensable) is a key player in the coupling between transcription and splicing. Why pre-spliceosome formation is ATP-dependent has been a perplexing question for many years, and this paper provides further support for the notion that this requirement is due to coupling. These authors’ findings also suggest that parts of the core splicing machinery evolved functions not related to intron-removal per se, but rather to facilitate co-transcriptional pre-mRNA processing. Moreover, this coupling may impact both splicing fidelity and the production of intron-less genes in yeast.