I'm studying alternative splicing in the context of cotranscriptional splicing. I've found a paper (Saeki & Svejstrup 2009, Sigurdsson et al. 2010, Close et al. 2012) that mentions that A-rich tracts cause pausing. The first paper does not provide a reference on this but all the other cite it and each other.
Is pol II pausing by A-rich tracts common knowledge or can anyone point me to some references?