Hemoglobin-Spectrin Complexes: Interference with Spectrin Tetramer Assembly as a Mechanism for Compartmentalization of Band 1 and Band 2 Complexes
Abstract
The irreducible complexation of hemoglobin with spectrin is a natural phenomenon of red cell aging, positively correlating with increasing cell density and decreasing cell deformability. The current study begins to address the role of these complexes in the disruption of membrane skeletal physiology and structure. The effect of bound hemoglobin on spectrin dimer self-association was investigated in vitro. The extent of conversion of isolated spectrin dimers to tetramers was evaluated as a function of peroxide-induced globin complexation prior to the conversion incubations. The incremental accumulation of tetramer was observed to decrease with increasing peroxide concentration used in the globin complexation step. The role of oxidized heme in this process was made apparent by the inability of carboxyhemoglobin to inhibit tetramer accumulation. A Western blot analysis of naturally formed globin-spectrin conjugates demonstrated irreducible complexes of globin with both bands 1 and 2. The complexes are tentatively designated "h1" and "h2". This analysis also demonstrated that hi is completely extractable from cell ghosts, whereas h2 is only 50% extractable. These findings are incorporated into a hypothesis linking globin-spectrin complexation and the consequent inhibition of spectrin dimer self-association to the clustered band 3 senescence antigen.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 06, 1994
- Accession Number
- ADA360323
Entities
People
- C. R. Kiefer
- C. R. Valeri
- J. B. Mckenney
- J. F. Trainor
- L. M. Snyder
Organizations
- Boston University