Cofactor for the transcription factor TCF7. Involved in regulation of lymphoid development by driving multipotent hematopoietic progenitor cells towards a T-cell fate. Interacts with HSPA8 and LAMP2 isoform A; the interaction may target MLLT11 for degradation via chaperone-mediated autophagy. Interacts with TCF7. Continuous nuclear export is followed by degradation. Ubiquitinated, leading to degradation. Belongs to the MLLT11 family.