ACTN4
ACTN4 (actinin alpha 4, also known as alpha-actinin-4 or FSGS1) is a nonmuscle F-actin cross-linking and bundling protein that is thought to anchor actin to a range of intracellular structures. It belongs to the alpha-actinin family. Browse Assay Genie's current range of ACTN4 research reagents below, or read on for the biology behind the target.
ACTN4 is an F-actin cross-linking protein with bundling activity, thought to anchor actin to a variety of intracellular structures. It is probably involved in vesicular trafficking through its association with the CART complex, which is necessary for efficient transferrin receptor recycling but not for EGFR degradation. In epithelial cells, ACTN4 is implicated in tight junction assembly, probably through interaction with MICALL2: it links MICALL2 to the actin cytoskeleton and recruits it to tight junctions.
Beyond the cytoskeleton, ACTN4 may act as a transcriptional coactivator, stimulating transcription mediated by the nuclear hormone receptors PPARG and RARA. Its association with IGSF8 regulates immune synapse formation and is required for efficient T-cell activation. This breadth of roles is reflected in its subcellular distribution, which spans the cytoplasm, stress fibres, perinuclear region, cell junctions and nucleus.
The ACTN4 gene encodes a nonmuscle alpha-actinin isoform that is concentrated in the cytoplasm. Alpha-actinins belong to the spectrin gene superfamily, which also includes the spectrins and dystrophins. In nonmuscle cells the cytoskeletal isoform lies along microfilament bundles and adherens-type junctions, where it binds actin to the membrane. ACTN4 is thought to be involved in metastatic processes, and mutations in the gene have been associated with focal and segmental glomerulosclerosis, which accounts for the earlier name focal segmental glomerulosclerosis 1 (FSGS1). Researchers studying the ACTN4 protein often compare it with other alpha-actinins such as ACTN3.
ACTN4 cross-links and bundles F-actin and is thought to anchor actin to intracellular structures, including stress fibres and adherens-type junctions.
ACTN4 is probably involved in tight junction assembly, linking MICALL2 to the actin cytoskeleton and recruiting it to junctions.
Mutations in the ACTN4 gene have been associated with focal and segmental glomerulosclerosis, making it a focus for glomerular disease studies.
ACTN4 association with IGSF8 regulates immune synapse formation and is required for efficient T-cell activation.
ACTN4 is an F-actin cross-linking and bundling protein thought to anchor actin to intracellular structures. It is probably involved in vesicular trafficking via the CART complex and in tight junction assembly via MICALL2, and may act as a coactivator of PPARG- and RARA-mediated transcription.
ACTN4 stands for actinin alpha 4, and UniProt names the protein alpha-actinin-4. The gene was previously designated FSGS1, from its former name focal segmental glomerulosclerosis 1, reflecting the disease association of its mutations. HGNC places it in the actinins gene group.
The gene has mouse and rat orthologs, both named Actn4, so it can be studied in rodent systems; check the datasheet of any product for its validated reactivity. Mutations in human ACTN4 have been associated with focal and segmental glomerulosclerosis, and the protein is thought to be involved in metastatic processes.
Other alpha-actinin family members and cytoskeletal targets with products at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt O43707; product specifications from Assay Genie datasheets.