| abstract |
The peptides, or pharmaceutically- or biologically-acceptable salts thereof, comprise the amino acid sequence of formula (I) wherein: aa 1 is histidine or isoleucine, aa 2 represents a spacing amino acid, aa 3 is cysteine or serine, n = 0 or 1; the amino acids constituting the peptide are L-amino acids, said amino acids being positioned in the peptide sequence in the order indicated in formula (I) or in the reverse order. Said peptides translocate through and penetrate the cell membrane, travelling specifically to the nucleolus. These properties render it useful as a system of directing a second molecule to the nucleolus. Tyr-Lys-Gln-(aa 3 )-(aa 1 )-Lys-Lys-Gly-Gly-(aa 2 ) n -Lys-Lys-Gly-Ser-Gly (I). |