RESUMO
A structurally novel liver X receptor (LXR) agonist (1) was identified from internal compound collection utilizing the combination of structure-based virtual screening and high-throughput gene profiling. Compound 1 increased ABCA1 gene expression by eightfold and SREBP1c by threefold in differentiated THP-1 macrophage cell lines. Confirmation of its agonistic activity against LXR was obtained in the co-factor recruitment and reporter transactivation assays. Structure-activity relationship studies on compound 1 are described.
Assuntos
Proteínas de Ligação a DNA/agonistas , Regulação da Expressão Gênica/efeitos dos fármacos , Indóis/farmacologia , Macrófagos/efeitos dos fármacos , Monócitos/efeitos dos fármacos , Receptores Citoplasmáticos e Nucleares/agonistas , Transportador 1 de Cassete de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Linhagem Celular , Regulação da Expressão Gênica/fisiologia , Humanos , Indóis/síntese química , Receptores X do Fígado , Macrófagos/metabolismo , Modelos Químicos , Monócitos/citologia , Receptores Nucleares Órfãos , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Relação Estrutura-AtividadeRESUMO
Dipeptidyl peptidase IV (DPPIV) is a serine protease, a member of the prolyl oligopeptidase (POP) family, and has been implicated in several diseases. Therefore, it seems important to develop selective inhibitors for human DPPIV (hDPPIV) that are able to control the biological function of hDPPIV. In order to elucidate the binding mode and substrate specificity, we determined the crystal structure complex of hDPPIV and diprotin A (IIe-Pro-IIe), a slowly hydrolyzed substrate of hDPPIV, at 2.2 A resolution. In this paper, we discuss the molecular interaction mechanism of diprotin A with hDPPIV based on the X-ray crystal structure.
Assuntos
Dipeptidil Peptidase 4/química , Oligopeptídeos/química , Sítios de Ligação , Cristalização , Cristalografia por Raios X , Humanos , Modelos Moleculares , Conformação Proteica , Estrutura Terciária de ProteínaRESUMO
Dipeptidyl peptidase IV (DPPIV) is a serine protease, a member of the prolyl oligopeptidase (POP) family, and has been implicated in several diseases. Therefore, the development of DPPIV selective inhibitors, which are able to control the biological function of DPPIV, is important. We determined the crystal structure of human DPPIV at 2.6A resolution. The molecule consists of a unique eight-bladed beta-propeller domain in the N-terminal region and a serine protease domain in the C-terminal region. Also, the large "cave" structure, which is thought to control the access of the substrate, is found on the side of the beta-propeller fold. Comparison of the overall amino acid sequence between human DPPIV and POP shows low homology (12.9%). In this paper, we report the structure of human DPPIV, especially focusing on a unique eight-bladed beta-propeller domain. We also discuss the way for the access of the substrate to this domain.
Assuntos
Dipeptidil Peptidase 4/química , Estrutura Secundária de Proteína , Sequência de Aminoácidos , Domínio Catalítico , Dipeptidil Peptidase 4/genética , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Prolil Oligopeptidases , Estrutura Terciária de Proteína , Alinhamento de Sequência , Serina Endopeptidases/química , Serina Endopeptidases/genéticaRESUMO
Human DPPIV has been expressed in the baculovirus system and purified and crystallized using the hanging-drop method. A crystal was obtained from 180 mM Gly-NaOH buffer pH 9.5 containing 18% PEG 4000 and 180 mM sodium acetate. The crystal belongs to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 118.04, b = 125.92, c = 136.84 A, and diffracts beyond 2.6 A resolution. There are two molecules per asymmetric unit, indicating a solvent content of 57.6%.