Coilin is a

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respo ...

that in humans is encoded by the ''COIL''

gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a ba ...

. Coilin got its name from the coiled shape of the

Cajal bodies Cajal bodies (CBs) also coiled bodies, are spherical nuclear bodies of 0.3–1.0 µm in diameter found in the nucleus of proliferative cells like embryonic cells and tumor cells, or metabolically active cells like neurons. CBs are membrane-le ...

in which it is found. It was first identified using human autoimmune serum.

Function

Coilin protein is one of the main molecular components of Cajal bodies. Cajal bodies are non-membrane bound

nuclear bodies Nuclear bodies (also known as nuclear domains, or nuclear dots) are membraneless structures found in the cell nuclei of eukaryotic cells. Nuclear bodies include Cajal bodies, the nucleolus, and promyelocytic leukemia protein (PML) nuclear bodies ...

of varying number and composition that are involved in the

post-transcriptional modification Transcriptional modification or co-transcriptional modification is a set of biological processes common to most eukaryotic cells by which an RNA primary transcript is chemically altered following transcription from a gene to produce a mature, func ...

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 nucleolus (, plural: nucleoli ) is the largest structure in the nucleus of eukaryotic cells. It is best known as the site of ribosome biogenesis, which is the synthesis of ribosomes. The nucleolus also participates in the formation of sig ...

. The

N-terminus The N-terminus (also known as the amino-terminus, NH2-terminus, N-terminal end or amine-terminus) is the start of a protein or polypeptide, referring to the free amine group (-NH2) located at the end of a polypeptide. Within a peptide, the ami ...

of the coilin protein directs its self-oligomerization while the

C-terminus The C-terminus (also known as the carboxyl-terminus, carboxy-terminus, C-terminal tail, C-terminal end, or COOH-terminus) is the end of an amino acid chain (protein or polypeptide), terminated by a free carboxyl group (-COOH). When the protein is ...

influences the number of nuclear bodies assembled per cell. Differential

methylation In the chemical sciences, methylation denotes the addition of a methyl group on a substrate, or the substitution of an atom (or group) by a methyl group. Methylation is a form of alkylation, with a methyl group replacing a hydrogen atom. These t ...

and

phosphorylation In chemistry, phosphorylation is the attachment of a phosphate group to a molecule or an ion. This process and its inverse, dephosphorylation, are common in biology and could be driven by natural selection. Text was copied from this source, wh ...

of coilin likely influences its localization among nuclear bodies and the composition and assembly of Cajal bodies. This gene has

pseudogene Pseudogenes are nonfunctional segments of DNA that resemble functional genes. Most arise as superfluous copies of functional genes, either directly by DNA duplication or indirectly by Reverse transcriptase, reverse transcription of an mRNA trans ...

s on chromosome 4 and chromosome 14. To study CBs, coilin can be combined with GFP (

Green Fluorescent Protein The green fluorescent protein (GFP) is a protein that exhibits bright green fluorescence when exposed to light in the blue to ultraviolet range. The label ''GFP'' traditionally refers to the protein first isolated from the jellyfish ''Aequorea ...

) to form Coilin-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

snRNP snRNPs (pronounced "snurps"), or small nuclear ribonucleoproteins, are RNA-protein complexes that combine with unmodified pre-mRNA and various other proteins to form a spliceosome, a large RNA-protein molecular complex upon which splicing of pre- ...

s and nucleolar snoRNPs. Coilin has been shown to

interact Advocates for Informed Choice, dba interACT or interACT Advocates for Intersex Youth, is a 501(c)(3) nonprofit organization using innovative strategies to advocate for the legal and human rights of children with intersex traits. The organizati ...

with

ataxin 1 Ataxin-1 is a DNA-binding protein which in humans is encoded by the ''ATXN1'' gene. Mutations in ataxin-1 cause spinocerebellar ataxia type 1, an inherited Neurodegeneration, neurodegenerative disease characterized by a progressive loss of cerebe ...

nucleolar phosphoprotein p130 Nucleolar phosphoprotein p130 is a protein that in humans is encoded by the ''NOLC1'' gene. Interactions Nucleolar phosphoprotein p130 has been shown to interact with coilin and CEBPB CCAAT/enhancer-binding protein beta is a protein that in ...

, SMN, and

SNRPB Small nuclear ribonucleoprotein-associated proteins B and B' is a protein that in humans is encoded by the ''SNRPB'' gene. Function The protein encoded by this gene is one of several nuclear proteins that are found in common among U1, U2, U4/U ...

Function

References

Further reading