Differential regulation of the coexpressed calcitonin/alpha-CGRP and beta-CGRP neuroendocrine genes.
The rat calcitonin/alpha-CGRP and beta-CGRP genes are members of a neuroendocrine gene family that are coexpressed in a distinct cell-specific pattern. The alpha- and beta-CGRP gene sequences predict highly related peptides that differ by only a single amino acid. Using rat medullary thyroid carcinoma cells as an in vitro system for testing hormone responsiveness, we have shown that the calcitonin/alpha-CGRP and beta-CGRP genes are differentially regulated. The synthetic glucocorticoid, dexamethasone, caused a 2- to 5-fold increase in calcitonin and alpha-CGRP mRNAs due to an increase in the nuclear transcription rate. In contrast, the levels of beta-CGRP mRNA did not significantly change following dexamethasone treatment. Differential regulation within neuroendocrine gene families might be a common mechanism for generating functionally similar peptides in response to a variety of hormonal signals.
Russo
A F
AF
Howard Hughes Medical Institute, School of Medicine, University of California, San Diego, La Jolla 92093.
Nelson
C
C
Roos
B A
BA
Rosenfeld
M G
MG
D002116:Calcitonin / Q000235:genetics*; D015740:Calcitonin Gene-Related Peptide; D002460:Cell Line; D003907:Dexamethasone / Q000494:pharmacology; D005796:Genes; D005809:Genes, Regulator; D006801:Humans; D009479:Neuropeptides / Q000235:genetics*; D013964:Thyroid Neoplasms; D014158:Transcription, Genetic / Q000187:drug effects
D009479:Neuropeptides; D003907:Dexamethasone; D002116:Calcitonin; D015740:Calcitonin Gene-Related Peptide