Abstract
Not all of the effects of thyroid-stimulating hormone (TSH) on the thyroid are mediated by activation of the adenylate cyclase-cyclic AMP system, indicating that other control systems must also exist. Although a calcium-phospholipid-dependent protein kinase (protein kinase C) and specific substrates had been identified in thyroid tissue, their responsiveness to TSH and other stimulators has not been determined. In thyroid cells which had been preloaded with [32P]orthophosphate, TSH and 12-O-tetradecanoyl-phor-bol-13-acetate (TPA) increased the phosphorylation of a 33K polypeptide substrate within 5 min in a dose-dependent fashion. The effect was observed with 1 mU/ml TSH and 3 nm TPA and was maximal with 100 mU/ml TSH and 100 nm TPA. The biologically inactive analog of TPA, 4α-phorbol, had no effect. Isobutylmethylxanthine (IBMX) decreased the phosphorylation of the 33K polypeptide and inhibited the effect of TSH and TPA, indicating that the phosphorylation is not mediated by cyclic AMP. TSH and IBMX, but not TPA, augmented phosphorylation of a 38K polypeptide, suggesting involvement of cyclic AMP. In contrast TPA, but not TSH, increased the phosphorylation of 58K and 28K polypeptides. TSH, but not TPA or 4α-phorbol, elevated the cyclic AMP level of thyroid slices. Incubation of thyroid slices with TSH or TPA significantly decreased protein kinase C activity in the 100,000g cytosol fraction and increased it in an extract of plasma membranes. The effect was present within 5 min and was maximal by 30 min. The effect was observed with 100 mU/ml TSH or 1 nm TPA. The stimulation by TSH or TPA of protein kinase C and its translocation from the cytosol to the plasma membranes of thyroid tissue may provide another mechanism for control of thyroid Cell metabolism.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 92-99 |
| Number of pages | 8 |
| Journal | Archives of Biochemistry and Biophysics |
| Volume | 243 |
| Issue number | 1 |
| DOIs | |
| State | Published - Nov 15 1985 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Biochemistry
- Biophysics
- Molecular Biology
Cite this
Thyroid cell responses to thyrotropin and 12-O-tetradecanoyl-phorbol-13-acetate : Translocation of protein kinase C and phosphorylation of thyroid cell polypeptide substrates. / Tanabe, Akira; Nielsen, Thor B.; Kadapakkam, Sheela R; Field, James B.
In: Archives of Biochemistry and Biophysics, Vol. 243, No. 1, 15.11.1985, p. 92-99.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Thyroid cell responses to thyrotropin and 12-O-tetradecanoyl-phorbol-13-acetate
T2 - Translocation of protein kinase C and phosphorylation of thyroid cell polypeptide substrates
AU - Tanabe, Akira
AU - Nielsen, Thor B.
AU - Kadapakkam, Sheela R
AU - Field, James B.
PY - 1985/11/15
Y1 - 1985/11/15
N2 - Not all of the effects of thyroid-stimulating hormone (TSH) on the thyroid are mediated by activation of the adenylate cyclase-cyclic AMP system, indicating that other control systems must also exist. Although a calcium-phospholipid-dependent protein kinase (protein kinase C) and specific substrates had been identified in thyroid tissue, their responsiveness to TSH and other stimulators has not been determined. In thyroid cells which had been preloaded with [32P]orthophosphate, TSH and 12-O-tetradecanoyl-phor-bol-13-acetate (TPA) increased the phosphorylation of a 33K polypeptide substrate within 5 min in a dose-dependent fashion. The effect was observed with 1 mU/ml TSH and 3 nm TPA and was maximal with 100 mU/ml TSH and 100 nm TPA. The biologically inactive analog of TPA, 4α-phorbol, had no effect. Isobutylmethylxanthine (IBMX) decreased the phosphorylation of the 33K polypeptide and inhibited the effect of TSH and TPA, indicating that the phosphorylation is not mediated by cyclic AMP. TSH and IBMX, but not TPA, augmented phosphorylation of a 38K polypeptide, suggesting involvement of cyclic AMP. In contrast TPA, but not TSH, increased the phosphorylation of 58K and 28K polypeptides. TSH, but not TPA or 4α-phorbol, elevated the cyclic AMP level of thyroid slices. Incubation of thyroid slices with TSH or TPA significantly decreased protein kinase C activity in the 100,000g cytosol fraction and increased it in an extract of plasma membranes. The effect was present within 5 min and was maximal by 30 min. The effect was observed with 100 mU/ml TSH or 1 nm TPA. The stimulation by TSH or TPA of protein kinase C and its translocation from the cytosol to the plasma membranes of thyroid tissue may provide another mechanism for control of thyroid Cell metabolism.
AB - Not all of the effects of thyroid-stimulating hormone (TSH) on the thyroid are mediated by activation of the adenylate cyclase-cyclic AMP system, indicating that other control systems must also exist. Although a calcium-phospholipid-dependent protein kinase (protein kinase C) and specific substrates had been identified in thyroid tissue, their responsiveness to TSH and other stimulators has not been determined. In thyroid cells which had been preloaded with [32P]orthophosphate, TSH and 12-O-tetradecanoyl-phor-bol-13-acetate (TPA) increased the phosphorylation of a 33K polypeptide substrate within 5 min in a dose-dependent fashion. The effect was observed with 1 mU/ml TSH and 3 nm TPA and was maximal with 100 mU/ml TSH and 100 nm TPA. The biologically inactive analog of TPA, 4α-phorbol, had no effect. Isobutylmethylxanthine (IBMX) decreased the phosphorylation of the 33K polypeptide and inhibited the effect of TSH and TPA, indicating that the phosphorylation is not mediated by cyclic AMP. TSH and IBMX, but not TPA, augmented phosphorylation of a 38K polypeptide, suggesting involvement of cyclic AMP. In contrast TPA, but not TSH, increased the phosphorylation of 58K and 28K polypeptides. TSH, but not TPA or 4α-phorbol, elevated the cyclic AMP level of thyroid slices. Incubation of thyroid slices with TSH or TPA significantly decreased protein kinase C activity in the 100,000g cytosol fraction and increased it in an extract of plasma membranes. The effect was present within 5 min and was maximal by 30 min. The effect was observed with 100 mU/ml TSH or 1 nm TPA. The stimulation by TSH or TPA of protein kinase C and its translocation from the cytosol to the plasma membranes of thyroid tissue may provide another mechanism for control of thyroid Cell metabolism.
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UR - http://www.scopus.com/inward/citedby.url?scp=0022403377&partnerID=8YFLogxK
U2 - 10.1016/0003-9861(85)90776-3
DO - 10.1016/0003-9861(85)90776-3
M3 - Article
C2 - 2415065
AN - SCOPUS:0022403377
VL - 243
SP - 92
EP - 99
JO - Archives of Biochemistry and Biophysics
JF - Archives of Biochemistry and Biophysics
SN - 0003-9861
IS - 1
ER -