The erythrocyte skeletons of beta-adducin deficient mice have altered levels of tropomyosin, tropomodulin and EcapZ.
The erythrocyte membrane cytoskeleton is organized as a polygonal spectrin network linked to short actin filaments that are capped by adducin at the barbed ends. We have constructed a mouse strain deficient in beta-adducin having abnormal erythrocytes. We show here that the levels of several skeletal proteins from beta-adducin mutant erythrocytes are altered. In fact, CapZ, the main muscle actin-capping protein of the barbed ends that in the erythrocytes is cytoplasmic, is 9-fold upregulated in mutant skeletons of erythrocytes suggesting a compensatory mechanism. We also detected upregulation of tropomodulin and downregulation of alpha-tropomyosin and actin. In addition, purified adducin can be re-incorporated into adducin-deficient ghosts.
International Centre for Genetic Engineering and Biotechnology, Padriciano 99, I 34012, Trieste, Italy.
Fabiola
F
Porro
Luisa
L
Costessi
Martín L
ML
Marro
Francisco E
FE
Baralle
Andrés F
AF
Muro
D000199:Actins / Q000378:metabolism*; D000818:Animals; D002148:Calmodulin-Binding Proteins / Q000172:deficiency* / Q000378:metabolism*; D002352:Carrier Proteins / Q000378:metabolism*; D015536:Down-Regulation; D004910:Erythrocyte Membrane / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008840:Microfilament Proteins / Q000378:metabolism*; D017510:Protein Folding; D051348:Tropomodulin; D014335:Tropomyosin / Q000378:metabolism*; D015854:Up-Regulation; D000099291:Adducins
D000199:Actins; D002148:Calmodulin-Binding Proteins; D002352:Carrier Proteins; D008840:Microfilament Proteins; D051348:Tropomodulin; D014335:Tropomyosin; D000099291:Adducins; C495831:Tmod1 protein, mouse