AJP - Cell Physiology, Vol 253, Issue 2 C286-C295, Copyright © 1987 by American Physiological Society
Band 3 tyrosine kinase in avian erythrocyte plasma membrane is immunologically related to pp60c-src
D. Hillsgrove, C. G. Shores, J. C. Parker and P. F. Maness
We have identified in the plasma membrane of the chicken erythrocyte a
60-kDa tyrosine-specific protein kinase immunologically related to the
transforming protein pp60v-src of Rous sarcoma virus. The erythrocyte
protein kinase phosphorylated heavy chains of tumor-bearing rabbit (TBR)
antibodies reactive with pp60c-src at tyrosine in immune complex protein
kinase assays. The kinase was identified as a 60-kDa protein by
[35S]methionine labeling of erythrocytes and by autophosphorylation in
immune complexes. The kinase migrated on two-dimensional gel
electrophoresis with an apparent pI and molecular mass similar to
pp60c-src. A plasma membrane-enriched fraction isolated from chicken red
cells contained the majority of the kinase activity. The kinase was
solubilized from the plasma membrane by the detergents 0.5% (wt/vol)
Na-deoxycholate and 1% (vol/vol) Nonidet P-40. One molar NaCl was much less
effective, indicating a strong association of the kinase with the plasma
membrane. Incubation of the plasma membrane fraction with [32P]ATP resulted
in tyrosine phosphorylation of the anion transport protein band 3. Band 3
phosphorylation was blocked by TBR antibodies, indicating that the kinase
recognized by pp60c-src antibodies was responsible for band 3
phosphorylation. These results demonstrate that the avian erythrocyte
plasma membrane contains a tightly bound tyrosine-specific protein kinase
identical or closely related to pp60c-src and that this kinase is
responsible for band 3 phosphorylation in vitro.
