Absence of fodrin (spectrin-like protein) under the pseudopod membrane in stimulated thyroid cells.
A fodrin-like protein purified from porcine thyroid cells and characterized by its properties identical to those of pig brain spectrin (F. Regnouf et al., Eur. J. Biochem. 153, 313-319 (1985)) has been localized by immunofluorescence and electron immunocytochemistry in porcine and rat thyroid. Fodrin-like polypeptides were detected in subplasmalemmal meshworks of microfilaments attached to isolated or in situ plasma membranes. In resting cells, fodrin was found under apical and basolateral membrane domains, whereas it was always absent under the pseudopod membrane domain induced by acute TSH stimulation in vitro, using monolayers of porcine cultured cells attached to collagen permeable substrates, as well as in vivo, using rats intravenously treated with TSH. Thyroid fodrin could be involved in exocytosis and membrane stabilization which occurs during the formation of pseudopods induced by TSH stimulation.
Gabrion
J B
JB
Laboratoire de Neurobiologie Endocrinologique, UA CNRS 1197, Université de Montpellier II, France.
Barrière
H
H
Nguyen Than Dao
B
B
Chambard
M
M
Mauchamp
J
J
Regnouf
F
F
Pradel
L A
LA
D000818:Animals; D000911:Antibodies, Monoclonal; D002352:Carrier Proteins / Q000032:analysis*; D002478:Cells, Cultured; D015925:Cryopreservation; D005455:Fluorescent Antibody Technique; D015151:Immunoblotting; D007124:Immunoenzyme Techniques; D008297:Male; D008565:Membrane Proteins / Q000032:analysis; D008840:Microfilament Proteins / Q000032:analysis*; D016253:Microscopy, Immunoelectron; D011554:Pseudopodia / Q000737:chemistry*; D051381:Rats; D011919:Rats, Inbred Strains; D013049:Spectrin / Q000032:analysis*; D013552:Swine; D013961:Thyroid Gland / Q000737:chemistry* / Q000166:cytology / Q000187:drug effects; D013972:Thyrotropin / Q000494:pharmacology
D000911:Antibodies, Monoclonal; D002352:Carrier Proteins; D008565:Membrane Proteins; D008840:Microfilament Proteins; D013049:Spectrin; D013972:Thyrotropin