Oligomerization of the plasma membrane calcium pump involves two regions with different thermal stability.
Ca(2+) pump dimerization was studied by using a combined approach of thermal denaturation and fluorescence resonance energy transfer. The measurement of calcium pump ability to dimerize after the unfolding of individual functional domains of the enzyme demonstrated the existence of two different regions involved in the self-association process. One of these regions is highly susceptible to thermal unfolding and was identified as the calmodulin (CaM)-binding domain. The other region whose thermal stability is higher than those of the catalytic and CaM-binding domains could be related with the previously found C28W-binding regions.
Levi
V
V
Departamento de Química Biológica-IQUIFIB, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, 1113 Buenos Aires, Argentina.
Rossi
J P
JP
Castello
P R
PR
González Flecha
F L
FL
D001665:Binding Sites; D000252:Calcium-Transporting ATPases / Q000737:chemistry* / Q000378:metabolism; D002147:Calmodulin / Q000378:metabolism; D002148:Calmodulin-Binding Proteins / Q000737:chemistry / Q000378:metabolism; D019281:Dimerization; D004910:Erythrocyte Membrane / Q000201:enzymology; D005453:Fluorescence; D006801:Humans; D007700:Kinetics; D011485:Protein Binding; D017510:Protein Folding; D013050:Spectrometry, Fluorescence; D013816:Thermodynamics
D002147:Calmodulin; D002148:Calmodulin-Binding Proteins; D000252:Calcium-Transporting ATPases