Coilin

Coilin, also known as COIL, is a human gene.

Coilin protein is one of the main molecular components of Cajal bodies (CBs). Cajal bodies are nuclear suborganelles of varying number and composition that are involved in the post-transcriptional modification of small nuclear and small nucleolar RNAs. In addition to its structural role, coilin acts as glue to connect the CB to the nucleolus. The N-terminus of the coilin protein directs its self-oligomerization while the C-terminus influences the number of nuclear bodies assembled per cell. Differential methylation and phosphorylation of coilin likely influences its localization among nuclear bodies and the composition and assembly of Cajal bodies. This gene has pseudogenes on chromosome 4 and chromosome 14.

To study CBs, coilin can be combined with GFP (Green Fluorescent Protein) to form Colin-GFP hybrid protein. The hybrid protein can then be used to locate CBs underneath a microscope, usually near the nucleolus of the cell. Other proteins that make up the CB include snRNPs and nucleolar snoRNPs.

Coilin got its name from the coiled shaped of the CB in which it is found. It was first identified using human autoimmune serum.