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 four 3-helix bundles 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
- ↑ Sjoblom B, Salmazo A, Djinovic-Carugo K. Alpha-actinin structure and regulation. Cell Mol Life Sci. 2008 Sep;65(17):2688-701. doi: 10.1007/s00018-008-8080-8. PMID:18488141 doi:https://dx.doi.org/10.1007/s00018-008-8080-8
- ↑ Bunnell TM, Burbach BJ, Shimizu Y, Ervasti JM. β-Actin specifically controls cell growth, migration, and the G-actin pool. Mol Biol Cell. 2011 Nov;22(21):4047-58. PMID:21900491 doi:10.1091/mbc.E11-06-0582
- ↑ Borrego-Diaz E, Kerff F, Lee SH, Ferron F, Li Y, Dominguez R. Crystal structure of the actin-binding domain of alpha-actinin 1: evaluating two competing actin-binding models. J Struct Biol. 2006 Aug;155(2):230-8. Epub 2006 Apr 25. PMID:16698282 doi:https://dx.doi.org/10.1016/j.jsb.2006.01.013
