Function
Actinin attaches the protein actin to the Z-lines in skeletal muscle cells and to dense bodies in smooth muscle cells.[1] Both ends of actinin contain an actin-binding domain (ABD). Actinin is encoded by different genes:
- ACTN1 encodes α-actinin-1 (aA1) which is a cytoskeletal isoform.
- ACTN2 encodes an isoform aA2 found in cardiac and skeletal muscles. For more details on ACTN2 see Group:MUZIC:actinin2.
- ACTN3 encodes aA3 which anchors actin at the muscle Z-disk.
- ACTN4 encodes aA4 which is found in the cytoplasm and is thought to be involved in metastasis.
- beta-ACTN regulates cell migration and gene expression through control of the cellular G-actin pool[2].
Structural highlights
Actinin contain which are called spectrin repeat (SR).[3] SR are found in proteins belonging to the cytoskeletal structure like spectrin and dystrophin.
3D Structures of Actinin
Actinin 3D structures