[en] Rhophilin 2 is a Rho GTPase binding protein initially isolated by differential screening of a chronically thyrotropin (TSH)-stimulated dog thyroid cDNA library. In thyroid cell culture, expression of rhophilin 2 mRNA and protein is enhanced following TSH stimulation of the cyclic AMP (cAMP) transduction cascade. Yeast two-hybrid screening and coimmunoprecipitation have revealed that the GTP-bound form of RhoB and components of the cytoskeleton are protein partners of rhophilin 2. These results led us to suggest that rhophilin 2 could play an important role downstream of RhoB in the control of endocytosis during the thyroid secretory process which follows stimulation of the TSH/cAMP pathway. To validate this hypothesis, we generated rhophilin 2-deficient mice and analyzed their thyroid structure and function. Mice lacking rhophilin 2 develop normally, have normal life spans, and are fertile. They have no visible goiter and no obvious clinical signs of hyper- or hypothyroidism. The morphology of thyroid cells and follicles in these mice were normal, as were the different biological tests performed to investigate thyroid function. Our results indicate that rhophilin 2 does not play an essential role in thyroid physiology
Behrends, J.; Université Libre de Bruxelles - ULB > Institut de Recherches Interdisciplinaires en Biologie Humaine et Moléculaire, Faculté de Médecine
Clement, S.; Université Libre de Bruxelles - ULB > Institut de Recherches Interdisciplinaires en Biologie Humaine et Moléculaire, Faculté de Médecine
Pajak, B.; Université Libre de Bruxelles - ULB > Institut de Biologie et de Médecine Moléculaires
Pohl, V.; Université Libre de Bruxelles - ULB > Institut de Recherches Interdisciplinaires en Biologie Humaine et Moléculaire, Faculté de Médecine
Maenhaut, C.; Université Libre de Bruxelles - ULB > Institut de Recherches Interdisciplinaires en Biologie Humaine et Moléculaire, Faculté de Médecine
Dumont, J. E.; Université Libre de Bruxelles - ULB > Institut de Recherches Interdisciplinaires en Biologie Humaine et Moléculaire, Faculté de Médecine
Schurmans, Stéphane ; Université Libre de Bruxelles - ULB > Institut de Recherche Interdisciplinaire en Biologie Humaine et Moleculaire
Language :
English
Title :
Normal thyroid structure and function in rhophilin 2-deficient mice
Publication date :
2005
Journal title :
Molecular and Cellular Biology
ISSN :
0270-7306
eISSN :
1098-5549
Publisher :
American Society for Microbiology (ASM), Washington, United States - District of Columbia
Volume :
25
Pages :
2846-2852
Peer reviewed :
Peer Reviewed verified by ORBi
Name of the research project :
EU Biomed 2 grant; Belgian Program on Interuniversity Poles of Attraction initiated by the Belgian State; Grant BE 2156
Funders :
FRSM - Fonds de la Recherche Scientifique Médicale DFG - Deutsche Forschungsgemeinschaft F.R.S.-FNRS - Fonds de la Recherche Scientifique
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