MAD2L1 Protein, Human (His-SUMO)

MAD2L1, a crucial component of the spindle-assembly checkpoint, plays a pivotal role in preventing anaphase onset until proper chromosome alignment is achieved at the metaphase plate. During prometaphase, MAD2L1, in its closed conformation, forms a heterotetrameric complex with MAD1L1 at unattached kinetochores, recruiting open conformation molecules of MAD2L1 (O-MAD2) and facilitating the conversion to the closed conformation. Essential for executing the mitotic checkpoint, MAD2L1 monitors kinetochore-spindle attachment, inhibits the anaphase promoting complex by sequestering CDC20, and ensures chromosomes' alignment before anaphase initiation. MAD2L1 can exist as a monomer, homodimer, or heterodimer with MAD1L1, forming a tetrameric core complex. It interacts with various proteins, including MAD2L1BP, ADAM17/TACE, CDC20, BUB1B, TTK, TPR, UBD, NEK2, and HSF1, contributing to its multifaceted roles in cell cycle regulation and mitotic progression. Interactions with isoforms of MAD1L1 lead to cytoplasmic sequestration, adding an additional layer of complexity to MAD2L1's regulatory functions.