Using the technique of fluorescence redistribution after photobleaching, we are studying the cellular mechanisms involved in localizing surface molecules to particular domains. A number of antigens localized to discrete surface regions have been identified with monoclonal antibodies on guinea pig sperm cells ( Primakoff , P., and D. G. Myles , 1983, Dev. Biol., 98:417-428). One of these monoclonal antibodies, PT-1, binds exclusively to the posterior tail region of the sperm cell surface. PT-1 recognizes an integral membrane protein that in complex with n-octyl-beta-D-glucopyranoside has a sedimentation coefficient of 6.8S in sucrose density gradients. Fluorescence redistribution after photobleaching measurements reveal that within its surface domain the PT-1 antigen diffuses rapidly (D = 2.5 X 10(-9) cm2/s) and completely (greater than 90% recovery after bleaching). These results rule out for this membrane protein all models that invoke immobilization as a mechanism for maintaining localization. We propose that the mechanism for localization of the PT-1 antigen may be a barrier to diffusion at the domain boundary.
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Article| May 01 1984
A localized surface protein of guinea pig sperm exhibits free diffusion in its domain.
D G Myles
D E Koppel
Online ISSN: 1540-8140
Print ISSN: 0021-9525
J Cell Biol (1984) 98 (5): 1905–1909.
D G Myles, P Primakoff, D E Koppel; A localized surface protein of guinea pig sperm exhibits free diffusion in its domain.. J Cell Biol 1 May 1984; 98 (5): 1905–1909. doi: https://doi.org/10.1083/jcb.98.5.1905
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