NLS are present only in nuclear proteins A typical NLs contains several consecutive basic amino acids (the positively charged Aa: Lys, Arg) Normal pyruvate kinase: Chimeric pyruvate kinase in cytosol containing sv40 Nls: in nucleus➢ NLS are present only in nuclear proteins A typical NLS contains several consecutive basic amino acids (the positively charged Aa: Lys, Arg) Normal pyruvate kinase: in cytosol Chimeric pyruvate kinase containing SV40 NLS: in nucleus