What does membrane fraction RNA-seq means in ENCODE project

Question

[Proxy Agent]

Hello everyone, I found that the RNA-Seq data of membrane fraction in the ENCODE project is quite confusing. What does the "membrane fraction" mean? Does it includes nuclear membrane, the ER membrane, etc? Could someone help me out? Thank you!

[GenoMax]

Take a look at the abstract of this paper for a possible explanation of membrane fraction. Someone else may have a direct link/explanation as applicable to ENCODE.