nMagHigh1 is a negatively charged engineered domain that can heterodimerize with a compatible positively charged 'pMag'-type domain upon stimulation with blue light. nMagHigh1 is based on VVD, a small light-oxygen-voltage (LOV) domain-containing protein encoded by the Neurospora crassa Vivid gene (UniProtKB:Q9C3Y6). It lacks the N-terminal 36 residues (to increase stability of the protein) and contains the amino acid substitutions I52D, M55G, M135I and M165I relative to the wild-type sequence (PMID:25708714).