STIL

SCL-interrupting locus protein is a protein that in humans is encoded by the STIL gene. STIL is present in many different cell types and is essential for centriole biogenesis. This gene encodes a cytoplasmic protein implicated in regulation of the mitotic spindle checkpoint, a regulatory pathway that monitors chromosome segregation during cell division to ensure the proper distribution of chromosomes to daughter cells. The protein is phosphorylated in mitosis and in response to activation of the spindle checkpoint, and disappears when cells transition to G1 phase. It interacts with a mitotic regulator, and its expression is required to efficiently activate the spindle checkpoint.

It is proposed to regulate Cdc2 kinase activity during spindle checkpoint arrest. Chromosomal deletions that fuse this gene and the adjacent locus commonly occur in T cell leukemias, and are thought to arise through illegitimate recombination events. Multiple transcript variants encoding different isoforms have been found for this gene. Multiple types of cancer produce STIL, and its expression is linked to an increased mitotic index and cancer development. Hedgehog family-mediated signaling events are one of its associated pathways. The development and function of the nervous system are impacted by STIL. The sequence of STIL gene is highly conserved in vertebrate species .Both fetal and adult tissues express the STIL gene. Its expression levels fluctuate with the cell cycle, making it challenging to detect in a complete tissue, particularly if the cells are not synchronized.