p19^INK4d: More than Just a Cyclin-Dependent Kinase Inhibitor

Cyclin-dependent kinase inhibitors (CDKIs) are important cell cycle regulators. The CDKI family is composed of the INK4 family and the CIP/KIP family. p19INK4d belongs to the INK4 gene family and is involved in a series of normal physiological activities and the pathogenesis of diseases. Many factors play regulatory roles in the p19INK4d gene expression at the transcriptional and posttranscriptional levels. p19INK4d not only regulates the cell cycle but also plays regulatory roles in apoptosis, DNA damage repair, cell differentiation of hematopoietic cells, and cellular senescence. In this review, the regulatory network of the p19INK4d gene expression and its biological functions are summarized, which provides a basis for further study of p19INK4d as a drug target for disease treatment.