GDP-GTP exchange factor for TEM1, a Ras-like protein, component of the mitotic exit network (MEN). Activation of TEM1 by LTE1 in the bud ultimately leads to activation of CDC15 followed by the release of CDC14 from the nucleolus, which then inactivates cyclin-dependent kinases (CDKs) activity by several mechanism. Required for TEM1 localization to the bud cortex during mitotic exit. Fine-tunes the timing of the mitotic exit and couples this event with cytokinesis. Involved in proprotein-processing like proalpha factor-processing in the secretory pathway. Interacts with CDC24, CDC42, KEL1, KEL2, RAS2 and TEM1. The localization to the bud requires interaction with KEL1, as well as the presence of septins, CDC42, CLA4 and RAS2. Phosphorylated by CDC28 in a cell cycle-dependent manner and in response to nocodazole. Dephosphorylion by CDC14 triggers LTE1 release from bud cortex during the exit of mitosis. Present with 304 molecules/cell in log phase SD medium. Belongs to the LTE1 family.