title: An alpha-subunit-secreting cell line derived from a mouse thyrotrope tumor.
abstract: The anterior pituitary contains multiple distinct endocrine cell types that secrete individual hormones. To derive a pure cell culture population in which to study the regulation of the alpha-subunit of TSH free of other hormones and cell types, we have developed a clonal continuous cell line from the transplantable thyrotrope tumor MGH101A. This cell line expresses alpha-subunit mRNA, secretes alpha-subunit protein, and has maintained a stable phenotype for over 3 yr in culture. However, as is the case for the transplantable tumor from which they are derived, these cells do not express the beta-subunit of TSH or respond to TRH or thyroid hormone. We have used this cell line to investigate regulation of the alpha-subunit mRNA by the second messengers, cAMP and phorbol esters, and by glucocorticoids. Phorbol esters increase alpha-subunit mRNA levels significantly (3.5-fold), as does cAMP (1.8-fold). In contrast, glucocorticoids decrease mRNA levels from cAMP-induced or basal levels (2-fold). These cells should prove valuable for study of alpha-subunit gene expression in an isolated renewable clonal cell culture system.
authors.affiliation: Regulatory Biology Laboratory, Salk Institute, La Jolla, California 92037.
authors.forename: I E
authors.initials: IE
authors.lastname: Akerblom
authors.forename: E C
authors.initials: EC
authors.lastname: Ridgway
authors.forename: P L
authors.initials: PL
authors.lastname: Mellon
mesh_terms: D000818:Animals; D002460:Cell Line; D005576:Colforsin / Q000494:pharmacology; D000242:Cyclic AMP / Q000494:pharmacology; D017362:Cyclic AMP Response Element-Binding Protein; D004268:DNA-Binding Proteins / Q000502:physiology; D003907:Dexamethasone / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000187:drug effects*; D015292:Glycoprotein Hormones, alpha Subunit / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D010903:Pituitary Gland, Anterior / Q000378:metabolism / Q000473:pathology*; D010911:Pituitary Neoplasms / Q000473:pathology*; D012045:Regulatory Sequences, Nucleic Acid; D015290:Second Messenger Systems; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D013973:Thyrotropin-Releasing Hormone / Q000494:pharmacology; D014157:Transcription Factors / Q000502:physiology; D014407:Tumor Cells, Cultured / Q000378:metabolism
chemical_list: D017362:Cyclic AMP Response Element-Binding Protein; D004268:DNA-Binding Proteins; D015292:Glycoprotein Hormones, alpha Subunit; D014157:Transcription Factors; D005576:Colforsin; D013973:Thyrotropin-Releasing Hormone; D003907:Dexamethasone; D000242:Cyclic AMP; D013755:Tetradecanoylphorbol Acetate