Monkeypox virus M1R protein (M1R)

The Monkeypox virus M1R protein is a highly conserved, myristoylated surface membrane protein located on the intracellular mature virion (IMV) form of the virus. It functions as a key component of the entry-fusion complex (EFC), which consists of 11 proteins and mediates the entry of the virion core into host cells during infection.[2][6][9] M1R shows 98.4% homology to the L1R protein of vaccinia virus, supporting its role in viral assembly and cellular entry processes essential for MPXV replication.[2] It exhibits high cross-reactivity (94%) with antibodies, particularly in B-cell epitopes overlapping regions 69–91 and 137–155 amino acids, making it a prominent immunogen.[2] M1R has been identified in vaccine candidates, such as multivalent nanoparticle vaccines displaying M1R alongside E8 and B6 proteins to elicit Th1/Th2 cellular immune responses including IFNγ, IL-2, and IL-4.[7] Structurally, it contributes to IMV envelopment and has been observed in plasma membrane-like or inclusion body formations.[2] As part of MPXV's conserved core genome, M1R supports the virus's brick-shaped morphology and cytoplasmic replication cycle, aiding dissemination in human hosts during mpox outbreaks.[2][4] No small-molecule drugs directly targeting M1R are reported, but its immunogenicity positions it for antibody-based therapeutics or diagnostics.[2][7]

Other names

L1R homolog