Does anybody know whether human angiogenin is inside the cell or on the cell surface? Do all kind of human cells have it? Its concentration inside the cell is low or kind of high? Thanks a lot.

The protein is endocytosed and translocated from the cell surface to the nucleus and goes to the nucleoli in endothelial cells. PLease read the following paper

http://www.pnas.org/cgi/reprint/91/5/1677.pdf#search=%22angiogenin%20is%20inside%20the%20cell%20or%20on%20the%20cell%20surface%22