A little question about internal promoter^_^

[CuteGold0407]

Hi,

Thank you for sharing your work!

I had a problem while reading your work. In the published paper, you said "We excluded internal promoters from our analysis with the junction read counts methods since the junction reads mapping to an internal intron cannot be unambiguously assigned to the promoters.", I wonder why the junction read mapping an internal intron cannot be? Is it for the biological reason(due to that it's a internal promoter? but why?) or the computational reason? and may I ask what is "the promoter that uses an internal intron"? Is that mean the promoter has a part of intron?

Sorry to disturb you and my question may sounds funny, but after googling I still didn't figure it out...Any reply is appreciated! Thanks!

Best wishes

Jeep Li