Recent Advances on Nucleolar Functions in Health and Disease.

The nucleolus is an internuclear organelle without a visible membrane via the light microscope inside the cell nucleus. It is the main site for synthesis of ribosome as a complex machine for coordinating protein production. It forms around a specific chromosomal feature called the nucleolar organizing region (NOR) which possesses numerous ribosomal DNA (rDNA). Although the nucleolus is best known as coordinator of ribosomal biogenesis and protein synthesis, recently, there is exciting awareness both on better understanding of ribosome biogenesis and non-ribosomal nucleolar functions. A great amount of research has clearly indicated that the nucleolus has functional activities in both ribosomal and non-ribosomal conditions such as development, aging, cell cycle, gene stability, lifespan regulation, and progeria. Through recent sophisticated and advanced technologies such as genomics, proteomics, metabolomics, advances of knowledge in RNA species and new approaches in microscopic analysis methods, researchers have shown that perturbation in the nucleolar structure and function (nucleolar stress) have been associated with human diseases including cancer, viral infection, cardiovascular and neurodegenerative diseases. In this review, we discuss the impact of current research providing new information regarding nucleolar roles and functions in some human diseases and aging.