Actinin
Encyclopedia
Actinin is a microfilament
protein. α-Actinin
is necessary for the attachment of actin
filaments to the Z-line
s in skeletal muscle cells, and to the dense bodies in smooth muscle cells. The functional protein is an anti-parallel dimer
, which cross-links the thin filaments in adjacent sarcomeres, and therefore coordinated contractions between sarcomeres in the horizontal axis.
The non-sarcomeric α-actinins (ACTN1 and ACTN4) are widely expressed. Both ends of the rod-shaped α-actinin dimer contain actin-binding domains.
Mutations in ACTN4 can cause the kidney disease focal segmental glomerulosclerosis
.
Microfilament
Microfilaments are the thinnest filaments of the cytoskeleton, a structure found in the cytoplasm of all eukaryotic cells. These linear polymers of actin subunits are flexible and relatively strong, resisting buckling by multi-piconewton compressive forces and filament fracture by nanonewton...
protein. α-Actinin
ACTN1
Alpha-actinin-1 is a protein that in humans is encoded by the ACTN1 gene.-Interactions:Actinin, alpha 1 has been shown to interact with PDLIM1, Collagen, type XVII, alpha 1, CDK5R1, Zyxin, Protein kinase N1, GIPC1, SSX2IP and CDK5R2....
is necessary for the attachment of actin
Actin
Actin is a globular, roughly 42-kDa moonlighting protein found in all eukaryotic cells where it may be present at concentrations of over 100 μM. It is also one of the most highly-conserved proteins, differing by no more than 20% in species as diverse as algae and humans...
filaments to the Z-line
Sarcomere
A sarcomere is the basic unit of a muscle. Muscles are composed of tubular muscle cells . Muscle cells are composed of tubular myofibrils. Myofibrils are composed of repeating sections of sarcomeres, which appear under the microscope as dark and light bands...
s in skeletal muscle cells, and to the dense bodies in smooth muscle cells. The functional protein is an anti-parallel dimer
Protein dimer
In biochemistry, a dimer is a macromolecular complex formed by two, usually non-covalently bound, macromolecules like proteins or nucleic acids...
, which cross-links the thin filaments in adjacent sarcomeres, and therefore coordinated contractions between sarcomeres in the horizontal axis.
The non-sarcomeric α-actinins (ACTN1 and ACTN4) are widely expressed. Both ends of the rod-shaped α-actinin dimer contain actin-binding domains.
Mutations in ACTN4 can cause the kidney disease focal segmental glomerulosclerosis
Focal segmental glomerulosclerosis
Focal segmental glomerulosclerosis is a cause of nephrotic syndrome in children and adolescents, as well as an important cause of kidney failure in adults.It is also known as "focal glomerular sclerosis" or "focal nodular glomerulosclerosis"....
.