Research output: Contribution to journal › Article › peer-review
Structural and aggregation features of a human κ-Casein fragment with antitumor and cell-penetrating properties. / Chinak, Olga A.; Shernyukov, Andrey V.; Ovcherenko, Sergey S. et al.
In: Molecules, Vol. 24, No. 16, 2919, 12.08.2019.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Structural and aggregation features of a human κ-Casein fragment with antitumor and cell-penetrating properties
AU - Chinak, Olga A.
AU - Shernyukov, Andrey V.
AU - Ovcherenko, Sergey S.
AU - Sviridov, Evgeniy A.
AU - Golyshev, Victor M.
AU - Fomin, Alexander S.
AU - Pyshnaya, Inna A.
AU - Kuligina, Elena V.
AU - Richter, Vladimir A.
AU - Bagryanskaya, Elena G.
PY - 2019/8/12
Y1 - 2019/8/12
N2 - Intrinsically disordered proteins play a central role in dynamic regulatory and assembly processes in the cell. Recently, a human κ-casein proteolytic fragment called lactaptin (8.6 kDa) was found to induce apoptosis of human breast adenocarcinoma MCF-7 and MDA-MB-231 cells with no cytotoxic activity toward normal cells. Earlier, we had designed some recombinant analogs of lactaptin and compared their biological activity. Among these analogs, RL2 has the highest antitumor activity, but the amino acid residues and secondary structures that are responsible for RL2's activity remain unclear. To elucidate the structure-activity relations of RL2, we studied the structural and aggregation features of this fairly large intrinsically disordered fragment of human milk κ-casein by a combination of physicochemical methods: NMR, paramagnetic relaxation enhancement (PRE), Electron Paramagnetic Resonance (EPR), circular dichroism, dynamic light scattering, atomic force microscopy, and a cytotoxic activity assay. It was found that in solution, RL2 exists as stand-alone monomeric particles and large aggregates. Whereas the disulfide-bonded homodimer turned out to be more prone to assembly into large aggregates, the monomer predominantly forms single particles. NMR relaxation analysis of spin-labeled RL2 showed that the RL2 N-terminal region, which is essential not only for multimerization of the peptide but also for its proapoptotic action on cancer cells, is more ordered than its C-terminal counterpart and contains a site with a propensity for ff-helical secondary structure.
AB - Intrinsically disordered proteins play a central role in dynamic regulatory and assembly processes in the cell. Recently, a human κ-casein proteolytic fragment called lactaptin (8.6 kDa) was found to induce apoptosis of human breast adenocarcinoma MCF-7 and MDA-MB-231 cells with no cytotoxic activity toward normal cells. Earlier, we had designed some recombinant analogs of lactaptin and compared their biological activity. Among these analogs, RL2 has the highest antitumor activity, but the amino acid residues and secondary structures that are responsible for RL2's activity remain unclear. To elucidate the structure-activity relations of RL2, we studied the structural and aggregation features of this fairly large intrinsically disordered fragment of human milk κ-casein by a combination of physicochemical methods: NMR, paramagnetic relaxation enhancement (PRE), Electron Paramagnetic Resonance (EPR), circular dichroism, dynamic light scattering, atomic force microscopy, and a cytotoxic activity assay. It was found that in solution, RL2 exists as stand-alone monomeric particles and large aggregates. Whereas the disulfide-bonded homodimer turned out to be more prone to assembly into large aggregates, the monomer predominantly forms single particles. NMR relaxation analysis of spin-labeled RL2 showed that the RL2 N-terminal region, which is essential not only for multimerization of the peptide but also for its proapoptotic action on cancer cells, is more ordered than its C-terminal counterpart and contains a site with a propensity for ff-helical secondary structure.
KW - Casein micelle
KW - Dimerization
KW - Disulfide bond
KW - Intrinsically disordered protein
KW - β-mercaptoethanol adduct
KW - APOPTOSIS
KW - intrinsically disordered protein
KW - beta-mercaptoethanol adduct
KW - dimerization
KW - casein micelle
KW - UNFOLDED PROTEINS
KW - LACTAPTIN
KW - PEPTIDE
KW - NMR CHARACTERIZATION
KW - disulfide bond
KW - INTRINSICALLY DISORDERED PROTEINS
KW - GROWTH
KW - DYNAMICS
UR - http://www.scopus.com/inward/record.url?scp=85070725238&partnerID=8YFLogxK
U2 - 10.3390/molecules24162919
DO - 10.3390/molecules24162919
M3 - Article
C2 - 31408975
AN - SCOPUS:85070725238
VL - 24
JO - Molecules
JF - Molecules
SN - 1420-3049
IS - 16
M1 - 2919
ER -
ID: 21238269