AJP - Cell Physiology, Vol 248, Issue 1 70-C79, Copyright © 1985 by American Physiological Society
Human erythrocyte membrane proteins of zone 4.5 exist as families of related proteins
C. F. Whitfield, D. B. Coleman, M. M. Kay, K. A. Shiffer, J. Miller and S. R. Goodman
An analysis of the polypeptide composition of zone 4.5 of human erythrocyte
membranes has been done by immunoautoradiographic and two-dimensional
peptide mapping techniques. Results of these studies demonstrated that the
Coomassie blue profile was constant, with 14 well-resolved bands present.
Zone 4.5 polypeptides existed as at least four families of two or more
components with closely related polypeptide backbones. The families could
be distinguished on the basis of their extraction characteristics,
immunological cross-reactivity, and two-dimensional peptide maps. One
family was related to protein 4.1, one family was related to band 3, and
two families were independent and not similar to other larger membrane
proteins. The data show that all of the visualized bands in zone 4.5 do not
have the same protein composition and that several closely related forms of
some polypeptides are present.
