First Author | Bruce LJ | Year | 2003 |
Journal | Blood | Volume | 101 |
Issue | 10 | Pages | 4180-8 |
PubMed ID | 12531814 | Mgi Jnum | J:83442 |
Mgi Id | MGI:2662026 | Doi | 10.1182/blood-2002-09-2824 |
Citation | Bruce LJ, et al. (2003) A band 3-based macrocomplex of integral and peripheral proteins in the RBC membrane. Blood 101(10):4180-8 |
abstractText | We have studied the membrane proteins of band 3 anion exchanger (AE1)-deficient mouse and human red blood cells. It has been shown previously that proteins of the band 3 complex are reduced or absent in these cells. In this study we show that proteins of the Rh complex are also greatly reduced (Rh-associated glycoprotein, Rh polypeptides, CD47, glycophorin B) or absent (LW). These observations suggest that the Rh complex is associated with the band 3 complex in healthy RBCs. Mouse band 3(-/-) RBCs differed from the human band 3-deficient RBCs in that they retained CD47. Aquaporin 1 was reduced, and its glycosylation was altered in mouse and human band 3-deficient RBCs. Proteins of the glycophorin C complex, and other proteins with independent cytoskeletal interactions, were present in normal or increased amounts. To obtain direct evidence for the association of the band 3 and the Rh protein complexes in the RBC, we examined whether Rh complex proteins were coimmunoprecipitated with band 3 from membranes. RhAG and Rh were found to be efficiently coimmunoprecipitated with band 3 from deoxycholate-solubilized membranes. Results suggest that band 3 forms the core of a macrocomplex of integral and peripheral RBC membrane proteins. The presence of these proteins in a single structural macrocomplex makes it likely that they have linked functional or regulatory roles. We speculate that this macrocomplex may function as an integrated CO(2)/O(2) gas exchange unit (metabolon) in the erythrocyte. |