Structural insights into mouse anti-apoptotic Bcl-xl reveal affinity for Beclin 1 and gossypol.
This study reports the crystal structures of Bcl-xl wild type and three Bcl-xl mutants (Y101A, F105A, and R139A) with amino acid substitutions in the hydrophobic groove of the Bcl-xl BH3 domain. An additional 12 ordered residues were observed in a highly flexible loop between the alpha1 and alpha2 helices, and were recognized as an important deamidation site for the regulation of apoptosis. The autophagy-effector protein, Beclin 1, contains a novel BH3 domain (residues 101-125), which binds to the surface cleft of Bcl-xl, as confirmed by nuclear magnetic resonance (NMR) spectroscopy and analytical gel-filtration results. Gossypol, a potent inhibitor of Bcl-xl, had a K(d) value of 0.9 microM. In addition, the structural and biochemical analysis of five Bcl-xl substitution mutants will provide structural insights into the design and development of anti-cancer drugs.
Priyadarshi
Amit
A
Biomedical Research Center, KIST, Republic of Korea.
Roy
Ankoor
A
Kim
Key-Sun
KS
Kim
Eunice EunKyeong
EE
Hwang
Kwang Yeon
KY
D019943:Amino Acid Substitution; D000818:Animals; D000970:Antineoplastic Agents / Q000737:chemistry; D051017:Apoptosis Regulatory Proteins / Q000737:chemistry*; D000071186:Beclin-1; D002850:Chromatography, Gel; D018360:Crystallography, X-Ray; D015195:Drug Design; D006072:Gossypol / Q000737:chemistry*; D051379:Mice; D019906:Nuclear Magnetic Resonance, Biomolecular; D011485:Protein Binding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D051020:bcl-X Protein / Q000037:antagonists & inhibitors* / Q000737:chemistry* / Q000235:genetics
D000970:Antineoplastic Agents; D051017:Apoptosis Regulatory Proteins; C494812:Bcl2l1 protein, mouse; D000071186:Beclin-1; C115010:Becn1 protein, mouse; D051020:bcl-X Protein; D006072:Gossypol