dc.creator | Wallis, C. J. | |
dc.creator | Wenegieme, Elizabeth F. | |
dc.creator | Babitch, Joseph A. | |
dc.date.accessioned | 2022-12-07T16:35:55Z | |
dc.date.available | 2022-12-07T16:35:55Z | |
dc.date.issued | 1992 | |
dc.identifier.uri | https://doi.org/10.1016/s0021-9258(18)42839-6 | |
dc.identifier.uri | https://repository.tcu.edu/handle/116099117/56606 | |
dc.description.abstract | Brain spectrin alpha and beta chains bind 45Ca2+, as shown by the calcium overlay method. Flow dialysis measurements revealed eight high affinity binding sites/tetramer that comprise two binding components (determined by nonlinear regression analysis). The first component has one or two sites (kd = 2-30 x 10(-8) M), depending on the ionic strength of the binding buffer, with the remaining high affinity sites in the second component (kd = 1-3 x 10(-6) M). In addition, there is a variable, low affinity binding component (n = 100-400, kd = 1-2 x 10(-4) M). Magnesium inhibits calcium binding to the low affinity sites with a K1 = 1.21 mM. Proteolytic fragments from trypsin or chymotrypsin digests of brain spectrin bind 45Ca2+ if they include alpha domain IV, alpha domain III, or the amino-terminal half of the beta chain (but more than 25 kDa from the amino-terminal). These data suggest that calcium ions bind with high affinity to the putative EF-hands in alpha domain IV and to one site in the amino-terminal half of the beta chain that is associated with alpha domain IV in the native dimer. The localization is consistent with a direct calcium modulation of the spectrin-actin-protein 4.1 interaction. In addition, there appears to be one high affinity site near the hypersensitive region of alpha brain spectrin. All four proposed binding sites occur near probable calmodulin-binding or calcium-dependent protease cleavage sites. | |
dc.language.iso | en_US | en_US |
dc.publisher | American Society for Biochemistry and Molecular Biology Inc. | |
dc.source | The Journal of biological chemistry | |
dc.subject | Binding site | |
dc.subject | Biophysics | |
dc.subject | Chemistry | |
dc.subject | Protease | |
dc.subject | Chymotrypsin | |
dc.subject | Tetramer | |
dc.subject | Trypsin | |
dc.subject | Spectrin | |
dc.subject | Calcium | |
dc.subject | Biochemistry | |
dc.subject | Dissociation constant | |
dc.subject | Animals | |
dc.subject | Autoradiography | |
dc.subject | Binding Sites | |
dc.subject | Blotting, Western | |
dc.subject | Brain/metabolism | |
dc.subject | Calcium/metabolism | |
dc.subject | Calmodulin/metabolism | |
dc.subject | Cations, Divalent | |
dc.subject | Cattle | |
dc.subject | Chymotrypsin/metabolism | |
dc.subject | Electrophoresis, Polyacrylamide Gel | |
dc.subject | Horses | |
dc.subject | Hydrolysis | |
dc.subject | Osmolar Concentration | |
dc.subject | Spectrin/metabolism | |
dc.subject | Trypsin/metabolism | |
dc.title | Characterization of calcium binding to brain spectrin | |
dc.type | Article | |
dc.rights.license | CC BY 4.0 | |
local.college | College of Science and Engineering | |
local.department | Chemistry and Biochemistry | |
local.persons | All (CHEM) | |