Hormonal regulation of thyroidal protein phosphokinase activities

Delbauffe, D.; Ohayon, Renée; Pavlović-Hournac, M.

doi:10.1016/0303-7207(79)90102-3

Cited by 17 publications

(6 citation statements)

References 57 publications

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“…Histone H I kinase activity measured in the presence of 2 pM cyclic-AMP and [3H]-cyclic-AMP binding occurs predominantly as a single peak at 155 mM KC1 (range 145-163 mM; n = 3). This finding is in agreement with Leonard et a1 [24] and Combest et a1 [27], but is in some disagreement with other findings [25]. Polyamine inhibition of the partially purified enzyme is qualitatively similar to studies performed using the crude supernatant fraction (data not shown).…”

Section: Resultssupporting

confidence: 92%

Differential effects of polyamines on rat thyroid protein kinase activities

Levasseur

Henricks

Poleck

et al. 1985

J of Cellular Biochemistry

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Ornithine decarboxylase, the rate-limiting enzyme in polyamine biosynthesis, has been shown to be regulated in thyroid by thyrotropin both in vivo and in vitro. Little, however, is known of the role of polyamines in thyroid cell function. Since studies in other tissues suggest that polyamines may influence protein phosphorylation, we studied the effect of the polyamines on various protein kinase activities in rat thyroid. Putrescine, spermidine, and spermine inhibit cyclic-AMP-dependent histone H1 kinase activity when measured in the cytosol fraction of rat thyroid; this effect is largely reproduced by NaCl concentrations of equivalent ionic strength. Both spermidine and spermine effect a 1.6-2.4-fold increase in cytosolic cyclic-AMP-independent (messenger-independent) casein kinase activity; stimulation by both polyamines is maximal at 5mM. A similar profile of stimulation is observed for messenger-independent casein kinase activity in crude nuclear preparations. Sodium chloride fails to stimulate both cytosolic and nuclear messenger-independent casein kinase activities at ionic strength equivalent to the spermine concentrations used. Spermine, but not putrescine, spermidine, or sodium chloride, inhibits calcium/phospholipid-dependent protein kinase C activity in cytosol extracts partially purified by DEAE chromatography. These findings suggest that regulation of protein kinase(s) by polyamines may represent a proximal locus (i) of action of thyrotropin-regulated ornithine decarboxylase activity in thyroid.

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Section: Resultssupporting

confidence: 92%

Differential effects of polyamines on rat thyroid protein kinase activities

Levasseur

Henricks

Poleck

et al. 1985

J of Cellular Biochemistry

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“…Our previous data had suggested that in thyroid glands PK II has apparently a greater instability than PK I; however from these data it was not possible to know if the more rapid decrease of PK II after some treatments was due to the selective degradation of the regulatory or of the catalytic subunits [18]. These results show that, upon dissociation, a part of the catalytic activity arising from PK II is selectively lost.…”

Section: Discussionmentioning

confidence: 81%

“…Under these conditions thyroidal cAMP-dependent protein kinases were recovered in 2 peaks: type I kinase corresponds to peak 1 which sediments at 4.9 S; type II kinase corresponds to peak 2, which sediments at 6.2 S [ 18,20]. For the estimation of sedimentation coefficients, myoglobin (S2o,w = 2) and glucose-oxidase (S2o,w = 7.93) were used as internal markers.…”

Section: Fractionation Of Protein Kinases By Sucrose Gradient Ultracementioning

confidence: 99%

“…Incubations were done at 30°C for 5 or 10 min. At the end of the incubation 150/al of the incubation mixture was spotted onto 2 cm discs of Whatmann 3 MM filter paper, which were thereafter processed as in [ 18].…”

Section: Estimation Of Protein Kinase Activitymentioning

confidence: 99%

“…A very small difference was also noted in their amino acid composition and primary structure [7]. Some data suggest that the 2 PK from several organs could have different stability upon hormonal and other treatments [16][17][18][19], but it is not known whether this is due to the properties of regulatory or catalytic subunits.…”

Section: Introductionmentioning

confidence: 99%

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Heterogeneity of the catalytic activity arising from thyroidal cAMP‐dependent protein kinase type II

1982

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Membrane IgM cross‐linking is not coupled to protein kinase C translocation in WEHI‐231 B lymphoma cells

1989

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The early molecular events involved in the process of signal transduction via membrane immunoglobulins (mIg) include phosphatidyl inositol metabolism, intracellular Ca2+ mobilization, and protein kinase C (PKC) activation. Anti-mIg antibodies exert either stimulating or inhibitory effects depending on the activation state and/or the differentiation stage of B cells. WEHI-231 is a murine B lymphoma that becomes inactivated upon anti-mIg treatment. This lymphoma has an immature B cell phenotype and is considered as a model for tolerance induction in B lymphocytes. In this study, we have investigated the relationship between mIg triggering, Ca2+ elevation, PKC translocation, and growth inhibition in WEHI-231 cells. Monoclonal antibodies to mu and kappa chains of the mIgM receptor promoted a rapid increase in intracytoplasmic Ca2+ and were potent inhibitors of cell growth. Ca2+ elevation and PKC translocation have been previously shown to be associated in B lymphocytes. To study the subcellular distribution of PKC in WEHI-231 cells, we used enzymatic assays and immunodetection methods. Although phorbol 12-myristate 13-acetate induced a rapid and almost complete redistribution of cytosolic PKC to the membrane fraction, anti-mIg treatment failed to modify the compartmentalization of PKC. These findings extend recent observations suggesting that B cell triggering through mIg receptors may involve additional pathways independent from PKC activation. PKC activation in normal B cells is also believed to provide a regulatory signal which limits the magnitude of the early signals produced by anti-mIg. Such a regulatory control is unlikely in WEHI-231 cells, due to the dissociation between Ca2+ mobilization and PKC translocation. Our findings therefore suggest that the sensitivity of immature B cells such as WEHI-231 to the inhibitory effects of anti-mIg antibodies may result in part from alterations of the phosphoinositide signal transduction pathway.

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Hormonal regulation of thyroidal protein phosphokinase activities

Cited by 17 publications

References 57 publications

Differential effects of polyamines on rat thyroid protein kinase activities

Differential effects of polyamines on rat thyroid protein kinase activities

Heterogeneity of the catalytic activity arising from thyroidal cAMP‐dependent protein kinase type II

Membrane IgM cross‐linking is not coupled to protein kinase C translocation in WEHI‐231 B lymphoma cells

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