Coactosin-like Protein (CotL1) is a cytoskeletal protein that is part of the ADF/Actin Depolymerizing Factor family of actin-binding proteins. Human CotL1 is 142 amino acids (aa) in length with a predicted molecular weight of approximately 16 kDa. It shares 95% aa sequence identity with the mouse and rat orthologs. It is principally composed of one ADF-H domain (aa 2-130) that contains a phosphorylation site at Ser115, and two acetylation sites at Lys102 and Lys126. There is one potential isoform variant that shows a 106 aa substitution for aa 1-53. Additionally, CotL1 may form noncovalent homodimers and oligomers when not bound to F-actin. CotL1 is widely expressed with the highest expression levels being found in placental, lung, kidney, and peripheral neutrophils. CotL1 has been found in low levels in the pancreas, liver, and brain. CotL1 interacts noncovalently with both F-actin and 5-Lipoxygenase/5LO. Research has also shown that CotL1 may function as a potential growth cone marker in elongating neurons.