Fibrillarin

Fibrillarin is a vital protein found in the nucleus of cells, primarily within structures called nucleoli, where it plays a key role in making ribosomes—the cell's protein factories. It functions as an enzyme that helps modify and process a type of RNA called pre-rRNA, ensuring proper assembly and function of ribosomes. Because ribosomes are essential for producing proteins, fibrillarin is crucial for cell growth and health. Abnormal levels or activity of fibrillarin are sometimes associated with diseases like cancer, highlighting its importance in normal cellular operations.