Kinetic analysis of the internalization and recycling of [3H]TRH and C-terminal truncations of the long isoform of the rat thyrotropin-releasing hormone receptor-1.

摘要: The C-terminal tail of the long splice variant rat thyrotropin-releasing hormone (TRH) receptor-1 (TRHR-1L) comprises around 93 amino acids. A series truncations was constructed and expressed transiently in HEK-293 cells. extent steady-state internalization these response to [(3)H]TRH dependent upon degree truncation. Little effect produced by deletion 50 acids, although there a substantial decrease 45-46 rate TRHR-1L ligand substantially decreased acid-wash procedures often used analysis cellular distribution receptors with peptide ligands, thus an alternative procedure using Mes-containing buffer employed present study. Apart from truncation anticipated eliminate post-translational acylation re-ceptor, which altered both association dissociation rates [(3)H]TRH, kinetics binding were unaffected Equally, recycling plasma membrane internalized Although full-length receptor impaired pre-exposure cells TRH, this not true mutants, displayed limited ratios. mutant also functional desensitization compared receptor.