Acts as a transcriptional coactivator for NOTCH proteins. Has been shown to amplify NOTCH-induced transcription of HES1. Potentiates activation by NOTCH3 and NOTCH4 more efficiently than MAML1 or MAML3. Interacts through its N-terminal region with the ankyrin repeat region of the Notch proteins NOTCH1, NOTCH2, NOTCH3 and NOTCH4. Forms a DNA-binding complex with Notch proteins and RBPSUH/RBP-J kappa. Nuclear, in a punctate manner. Widely expressed with high levels detected in placenta, salivary gland and skeletal muscle. The C-terminal domain is required for transcriptional activation. A chromosomal aberration involving MAML2 is found in mucoepidermoid carcinomas, benign Warthin tumors and clear cell hidradenomas. Translocation t(11;19)(q21;p13) with CRTC1. The fusion protein consists of the N-terminus of CRTC1 joined to the C-terminus of MAML2. The reciprocal fusion protein consisting of the N-terminus of MAML2 joined to the C-terminus of CRTC1 has been detected in a small number of mucoepidermoid carcinomas. Belongs to the mastermind family. Extended N-terminus.