Carvalho_2009_J.Membr.Biol_228_89

Reference

Title : Modulation of erythrocyte acetylcholinesterase activity and its association with G protein-band 3 interactions - Carvalho_2009_J.Membr.Biol_228_89
Author(s) : Carvalho FA , de Almeida JP , Freitas-Santos T , Saldanha C
Ref : J Membr Biol , 228 :89 , 2009
Abstract :

Circulating acetylcholine, substrate of membrane acetylcholinesterase (AChE), is known to enhance the band 3 protein degree of phosphorylation. The purpose of this study was to verify whether the band 3 phosphorylation status is associated with a G protein and whether it is an influent factor on AChE enzyme activity. From blood samples of healthy donors, erythrocyte suspensions were prepared and incubated with AChE substrate (acetylcholine) and inhibitor (velnacrine), along with protein tyrosine kinase (PTK) and tyrosine phosphatase (PTP) inhibitors. AChE activity was determined by spectrophotometry and extract samples were analyzed by western blotting using primary antibodies to different G protein subunits. Our results with phosphorylated band 3 (PTP inhibitor) show an increase in erythrocyte AChE (p < 0.0001). A dephosphorylated band 3 state (PTK inhibitor) shows a significant decrease. We identified a potential linkage of protein subunits Galpha(i1/2) and G(beta) with band 3 protein. Galpha(i1/2) and G(beta) may be linked to the band 3 C-terminal site. Galpha(i1/2) is associated with the band 3 N-terminal domain, except for the control and ACh aliquots. G(beta) is associated with both phosphorylated and dephosphorylated band 3 in the presence of velnacrine. We conclude that an erythrocyte G protein with subunits Galpha(i1/2) and G(beta) is associated with band 3. AChE depends on the degree of band 3 phosphorylation and its association with Galpha(i1/2) and G(beta).

PubMedSearch : Carvalho_2009_J.Membr.Biol_228_89
PubMedID: 19294450

Related information

Inhibitor Velnacrine

Citations formats

Carvalho FA, de Almeida JP, Freitas-Santos T, Saldanha C (2009)
Modulation of erythrocyte acetylcholinesterase activity and its association with G protein-band 3 interactions
J Membr Biol 228 :89

Carvalho FA, de Almeida JP, Freitas-Santos T, Saldanha C (2009)
J Membr Biol 228 :89