The tumor susceptibility gene 101 (TSG101) was first discovered in a screen for potential tumor suppressors. Altered transcripts of this gene have been detected in sporadic breast carcinomas and other malignancies. In mice the gene has been shown to be essential for growth, proliferation and survival of mammary epithelial cells. TSG101 is also a component of the ESCRt-1 complex, a regulator of the vesicular trafficking process. In addition it is required for the sorting of endocytic ubiquitinated cargos into multivesicular bodies and is involved the budding of many viruses.Synonyms: ESCRT-I complex subunit TSG101, Tumor susceptibility gene 101 protein