Tubulin pools in human erythrocytes: altered distribution in hypertensive patients affects Na⁺, K⁺-ATPase activity

• Published in: Cellular and molecular life sciences : CMLS Vol. 68; no. 10; pp. 1755 - 1768
• Main Authors: Amaiden, Marina R, Santander, Verónica S, Monesterolo, Noelia E, Campetelli, Alexis N, Rivelli, Juan F, Previtali, Gabriela, Arce, Carlos A, Casale, César H
• Format: Journal Article
• Language: English
• Published: Basel Basel : SP Birkhäuser Verlag Basel 01-05-2011; SP Birkhäuser Verlag Basel
• Subjects: Acetylation; Adult; Aged; antibodies; Antibodies, Monoclonal - immunology; Biochemistry; Biomedical and Life Sciences; Biomedicine; Cell Biology; Cell Membrane - metabolism; enzyme inhibition; enzymes; erythrocytes; Erythrocytes - drug effects; Erythrocytes - enzymology; Female; Humans; Hypertension - blood; Hypertension - enzymology; Life Sciences; Male; Middle Aged; Nocodazole - pharmacology; paclitaxel; Paclitaxel - pharmacology; patients; Research Article; sodium; Sodium-Potassium-Exchanging ATPase - metabolism; tubulin; Tubulin - metabolism; Hypertension; Human erythrocytes; Na; ATPase; Detyrosinated tubulin; K; Acetylated tubulin
• ISSN: 1420-682X; 1420-9071
• DOI: 10.1007/s00018-010-0549-6

The presence of tubulin in human erythrocytes was demonstrated using five different antibodies. Tubulin was distributed among three operationally distinguishable pools: membrane, sedimentable structure and soluble fraction. It is known that in erythrocytes from hypertensive subjects (HS), the Na⁺, K⁺-ATPase (NKA) activity is partially inhibited as compared with erythrocytes from normal subjects (NS). In erythrocytes from HS the membrane tubulin pool is increased by ~150%. NKA was found to be forming a complex with acetylated tubulin that results in inhibition of enzymes. This complex was also increased in erythrocytes from HS. Treatment of erythrocytes from HS with nocodazol caused a decrease of acetylated tubulin in the membrane and stimulation of NKA activity, whereas taxol treatment on erythrocytes from NS had the opposite effect. These results suggest that, in erythrocytes from HS, tubulin was translocated to the membrane, where it associated with NKA with the consequent enzyme inhibition.