The cell-specific expression and tissue distribution of c-erbA proteins alpha and beta is still unknown. To address this problem, we prepared anti-peptide antibodies directed against epitopes of human (h) c-erbA, specific for the alpha or beta form of thyroid hormone receptors. The cDNAs coding for h c-erbA beta-1, alpha-1 and alpha-2 were transcribed and the mRNAs were translated in vitro in the presence of 35S-methionine, and then their reactivity with the antisera was evaluated. The antiserum anti-beta-62-81 immunoprecipitated only the beta-1 receptor. The antiserum anti-alpha-144-162 determined precipitation of both alpha-1 and alpha-2 proteins but not of the beta-1 receptor. Anti-alpha-2 431-451 produced a selective precipitation of alpha-2, and had no effect on alpha-1 or beta-1 receptor. In order to study the interaction of the antibodies with native T3 receptor we evaluated the binding of antibodies to rat liver T3 receptors by Sephacryl S300 chromatography: both antisera anti-beta-62-81 and anti-alpha-144-162 caused a partial shift of the labeled T3-receptor complex to a higher molecular form, while the antibody directed against cerbA alpha-2 did not produce any significant shift. The anti-peptide antibodies were then immunopurified by affinity chromatography and used to immunolocalize the different forms of c-erb A proteins in adult and fetal rat liver, by a sensitive immunohistochemical technique. All 3 antibodies stained mainly the nuclei of the majority of adult liver cells. No staining was detectable when the original antiserum was deprived of anti-peptide antibodies by running through the affinity columns or when the antibodies were pre-absorbed with the homologous peptide. No significant staining was present in the liver from rat fetus.
Site-specific anti-c-erb A antibodies recognizing native thyroid hormone receptors: their use to detect the expression and localization of alpha and beta c-erb A proteins in rat liver
MACCHIA, ENRICO;BOGAZZI, FAUSTO;FONTANINI, GABRIELLA;
1992-01-01
Abstract
The cell-specific expression and tissue distribution of c-erbA proteins alpha and beta is still unknown. To address this problem, we prepared anti-peptide antibodies directed against epitopes of human (h) c-erbA, specific for the alpha or beta form of thyroid hormone receptors. The cDNAs coding for h c-erbA beta-1, alpha-1 and alpha-2 were transcribed and the mRNAs were translated in vitro in the presence of 35S-methionine, and then their reactivity with the antisera was evaluated. The antiserum anti-beta-62-81 immunoprecipitated only the beta-1 receptor. The antiserum anti-alpha-144-162 determined precipitation of both alpha-1 and alpha-2 proteins but not of the beta-1 receptor. Anti-alpha-2 431-451 produced a selective precipitation of alpha-2, and had no effect on alpha-1 or beta-1 receptor. In order to study the interaction of the antibodies with native T3 receptor we evaluated the binding of antibodies to rat liver T3 receptors by Sephacryl S300 chromatography: both antisera anti-beta-62-81 and anti-alpha-144-162 caused a partial shift of the labeled T3-receptor complex to a higher molecular form, while the antibody directed against cerbA alpha-2 did not produce any significant shift. The anti-peptide antibodies were then immunopurified by affinity chromatography and used to immunolocalize the different forms of c-erb A proteins in adult and fetal rat liver, by a sensitive immunohistochemical technique. All 3 antibodies stained mainly the nuclei of the majority of adult liver cells. No staining was detectable when the original antiserum was deprived of anti-peptide antibodies by running through the affinity columns or when the antibodies were pre-absorbed with the homologous peptide. No significant staining was present in the liver from rat fetus.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
