Overview:

ADD1 or Adducin 1 is a heterodimeric protein associated with the erythrocyte membrane skeleton, which promotes binding of spectrin to actin, and is a substrate for PKC and PKA (1). Alpha- and gamma-adducins are ubiquitously expressed while beta-adducin is expressed at high levels in brain and hematopoietic tissues. ADD1 can completely block elongation and depolymerization at the fast-growing barbed ends of actin filaments in vitro and this suggests that adducin restrict actin filament length in erythrocytes (2).

References:

1. Gardner, K. et.al: A new erythrocyte membrane-associated protein with calmodulin binding activity: identification and purification. J. Biol. Chem. 261: 1339-1348, 1986.

2. Kuhlman. et.al: A new functions for adducin: calcium/calmodulin-regulated capping of the barbed ends of actin filaments. J. Biol. Chem. 271: 7986-7991, 1996.