DNA-binding protein involved in S phase checkpoint control-coupled apoptosis by mediating p53/TP53-induced apoptosis. Has the ability to inhibit DNA synthesis and S phase arrest coupled to apoptosis. Has affinity to both double- and single-stranded DNA.
Cell growth arrest and apoptosis are two best-known biological functions of tumor-suppressor p53. However, genetic evidence indicates that not only is p21 the major mediator of G(1) arrest, but also it can prevent apoptosis with an unknown mechanism. Here, we report the discovery of a p53 target gene dubbed killin, which lies in close proximity to pten on human chromosome 10 and encodes a 20-kDa nuclear protein. We show that Killin is not only necessary but also sufficient for p53-induced apoptosis. Genetic and biochemical analysis demonstrates that Killin is a high-affinity DNA-binding protein, which potently inhibits eukaryotic DNA synthesis in vitro and appears to trigger S phase arrest before apoptosis in vivo. The DNA-binding domain essential for DNA synthesis inhibition was mapped to within 42 amino acid residues near the N terminus of Killin. These results support Killin as a missing link between p53 activation and S phase checkpoint control designed to eliminate replicating precancerous cells, should they escape G(1) blockade mediated by p21.
A programmed cell death process which begins when a cell receives an internal (e.g. DNA damage) or external signal (e.g. an extracellular death ligand), and proceeds through a series of biochemical events (signaling pathways) which typically lead to rounding-up of the cell, retraction of pseudopodes, reduction of cellular volume (pyknosis), chromatin condensation, nuclear fragmentation (karyorrhexis), plasma membrane blebbing and fragmentation of the cell into apoptotic bodies. The process ends when the cell has died. The process is divided into a signaling pathway phase, and an execution phase, which is triggered by the former.
The progression of biochemical and morphological phases and events that occur in a cell during successive cell replication or nuclear replication events. Canonically, the cell cycle comprises the replication and segregation of genetic material followed by the division of the cell, but in endocycles or syncytial cells nuclear replication or nuclear division may not be followed by cell division.
Protein involved in apoptotic programmed cell death. Apoptosis is characterized by cell morphological changes, including blebbing, cell shrinkage, nuclear fragmentation, chromatin condensation and chromosomal DNA fragmentation, and eventually death. Unlike necrosis, apoptosis produces cell fragments, called apoptotic bodies, that phagocytic cells are able to engulf and quickly remove before the contents of the cell can spill out onto surrounding cells and cause damage. In general, apoptosis confers advantages during an organism's life cycle.
Protein involved in the complex series of events by which the cell duplicates its contents and divides into two. The eukaryotic cell cycle can be divided in four phases termed G1 (first gap period), S (synthesis, phase during which the DNA is replicated), G2 (second gap period) and M (mitosis). The prokaryotic cell cycle typically involves a period of growth followed by DNA replication, partition of chromosomes, formation of septum and division into two similar or identical daughter cells.
A reference proteome is a set of protein sequences derived from a complete proteome which constitutes a defined standard for a particular user community. Reference proteomes are manually defined according to a number of criteria. They cover the proteomes of well- studied model organisms and other proteomes of interest for biomedical and biotechnological research. Reference proteomes have been selected to provide broad coverage of the tree of life, and constitute a representative cross-section of the taxonomic diversity to be found within UniProtKB.