Backbone Assignments of Human MCM6 NTD1 and Evaluation of Its Interaction with Peptides Originated from BLM Helicase

Abstract

MCM6 is a core subunit of the eukaryotic MCM2 to 7 helicase essential for DNA replication and often overexpressed in various cancers. We report backbone assignments for the human MCM6 N-terminal domain 1 (NTD1), spanning residues 15-115, and test its binding to BLM peptides MBD-N and MBD-D. The [1H- 15N] HSQC spectrum indicates that the MCM6 NTD1 is well folded. Chemical shift–based analysis supports a compact α/β architecture consistent with AlphaFold and cryo-EM models of the MCM complex. HSQC titrations with both BLM peptides show no significant chemical shift perturbations, indicating no detectable binding under the conditions used. These data suggest that additional regions or oligomeric context are required for stable MCM6–BLM interaction.