This entry represents target of rapamycin complex subunit LST8 (MLST8 or GbetaL), a component of both mTORC1 and mTORC2, complexes that regulate cell growth in response to nutrients. The mTORC1 complex consists of MTOR, MLST8, RPTOR, AKT1S1/PRAS40 and DEPTOR. The mTORC2 complex contains MTOR, MLST8, PRR5, RICTOR, MAPKAP1 and DEPTOR []. In mTORC1, MLST8 interacts directly with MTOR and enhances its kinase activity [].This entry also includes the target of rapamycin complex subunit wat1 (pop3 or wat1) from Schizosaccharomyces pombe, which is also a component of yeast TORC1 and TORC2 complexes. The subunits of TORC1 in fission yeasts are known as mip1, pop3/wat1, tco89, toc1 and tor2; and the subunits of the TORC2 complex are bit61, pop3/wat1, sin1, ste20 and tor1 [].