perinatal. relating to the period shortly before and after birth; the actual time varies between species. The last 10 to 15% of the pregnancy before parturition to the end of a comparable period after birth would cover present usage of the term. perinatal mortality. the percentage of animals in the danger period which die, as a ratio of the total number exposed.
Normal Gene Tumor Suppressor Gene Is nicknamed the Guardian of the Genome.. Can arrest the cell cycle, trigger apoptosis or senescence, and repair DNA. Chromosome 17 Cell Survival Produces a protein called tumor protein p53, which regulates cell division.
The cell cycle is controlled by the products of two classes of genes, proto-oncogenes and tumor suppressor genes. Normally the expression of these genes is balanced. 1. Proto-oncogenes encode proteins that promote cell division (These proteins act like the gas pedal on a car.. Cyclins: a family of proteins that regulate the timing of the cell cycle. These proteins trigger cell division. Internal regulators: several proteins make sure the cell cycle does not proceed unless certain processes have happened inside the cell.