Cell Fractionation smooth microsome fraction guinea pig pancreasJamieson, James D5/1/19613.25 in. x 4 in. Lantern SlidesCell fractionation confirmed that newly synthesized acinar cell secretory proteins moved from the RER to the periphery of the Golgi in the lumen of a smooth-surfaced membrane bounded compartment. This paper also describes the pancreatic slice system and the pulse-chase protocol used to label newly synthesized secretory proteins with radioactive leucine. The micrograph shows smooth microsomes obtained from the top band in the photograph of sucrose density gradient.Original Magnification: x10,000still image