Similar Intracellular Peptide Profile of TAP1/beta 2 Microglobulin Double-Knockout Mice and C57BL/6 Wild-Type Mice as Revealed by Peptidomic Analysis

• Autor(a) principal: Castro, Leandro Mantovani de [UNIFESP]
• Data de Publicação: 2010
• Outros Autores: Berti, Denise A., Russo, Lilian C., Coelho, Veronica, Gozzo, Fabio C., Oliveira, Vitor [UNIFESP], Ferro, Emer Suavinho [UNIFESP]
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNIFESP
• Texto Completo: http://repositorio.unifesp.br/handle/11600/33096; http://dx.doi.org/10.1208/s12248-010-9224-y
• topic: intracellular peptide; mass spectrometry; MHC-I antigen presentation; peptidome; proteasome

Cells produce and use peptides in distinctive ways. in the present report, using isotope labeling plus semi-quantitative mass spectrometry, we evaluated the intracellular peptide profile of TAP1/beta 2m(-/-) (transporter associated with antigen-processing 1/beta 2 microglobulin) double-knockout mice and compared it with that of C57BL/6 wild-type animals. Overall, 92 distinctive peptides were identified, and most were shown to have a similar concentration in both mouse strains. However, some peptides showed a modest increase or decrease (similar to 2-fold), whereas a glycine-rich peptide derived from the C-terminal of neurogranin (KGPGPGGPGGAGGARGGAGGGPSGD) showed a substantial increase (6-fold) in TAP1/beta 2m(-/-) mice. Thus, TAP1 and beta 2microglobulin have a small influence on the peptide profile of neuronal tissue, suggesting that the presence of peptides derived from intracellular proteins in neuronal tissue is not associated with antigens of the class I major histocompatibility complex. Therefore, it is possible that these intracellular peptides play a physiological role.