Theoretical studies of the role of C-terminal cysteines in the process of S-nitrosylation of human Src kinases

Autor(es)

Andre, Fernanda R. ^[1] ; dos Santos, Paloma Freire ^[1] ; Rando, Daniela G. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Paulo, Inst Ciencias Ambientais Quim & Farmaceut, Campus Diadema, Rua Sao Nicolau 210, 2 Andar, Diadema, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Molecular Modeling; v. 22, n. 1 JAN 2016.
• Citações Web of Science: 5

Resumo

Src tyrosine kinases are a family of non-receptor proteins that are responsible for the growth process, cellular proliferation, differentiation and survival. Lack of Src kinase control has been associated with the development of certain human cancers. This family of proteins is constituted of four domains, with SH1 being the kinase or catalytic domain. SH1 also presents three important regulatory sites. Two residues, Tyr416 and Tyr527, are responsible for important phosphorylation processes that lead to, respectively, activation and deactivation of these kinases. More recently, however, a set of four cysteine residues located near the C-terminus-Cys483, Cys487, Cys496 and Cys498-has been associated with the activation of the Src kinases through S-nitrosylation reactions. Particularly, the Cys498 has been specified as a fundamental residue when considering this regulatory mechanism. Aiming to understand the role of these four cysteines in S-nitrosylation, theoretical studies of electrostatic, steric and hydrophobic properties were performed with a sequence of 20 amino acids, enclosing the four cysteine residues under study, extracted from the PDB coordinates of the crystal obtained from the inactive state of Src kinase. Results indicate that Cys498 is buried deeply in the protein, in hydrophobic surroundings in which NO is more likely to suffer decomposition into the electrophilic intermediates known to be responsible for S-nitrosylation reactions. Electronic calculated properties, such as punctual atomic charges, electrostatic potentials and molecular orbital energy, also demonstrated the good nucleophilic potential of Cys498. (AU)

• Processo FAPESP: 13/01875-0 - Síntese paralela, screening in vitro e estudos de relação estrutura-atividade de nitroderivados ativos contra patógenos infectantes de macrófagos: Mycobacterium tuberculosis formas NRP e Leishmania sp
• Beneficiário: Daniela Goncales Galasse Rando
• Modalidade de apoio: Auxílio à Pesquisa - Regular