Cell cycle dependent exposure of a high molecular weight protein on the surface of mouse L cells

The non-penetrating lactoperoxidase iodination probe has been employed in conjunction with synchronously dividing populations of mouse L cells to identify a high molecular weight protein which is preferentially exposed on the L cell surface during G1 phase of the cell cycle. Progression of cells from G1 to S is accompanied by a marked decrease in the availability of this structure, called band 1, to lactoperoxidase-catalyzed iodination and it remains unavailable until cells re-enter G1. It is suggested that the band 1 polypeptide may be functionally involved in the regulation of L cell growth.