Insulin stimulation of high frequency phosphorylation dynamics in murine erythroleukemia cells

Ferreira, Gisela; Hammond, Kate; Gilbert, D.A.

doi:10.1016/0303-2647(94)90059-0

Cited by 23 publications

(8 citation statements)

References 17 publications

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“…Expression of PP1 and PP2A in proliferating and HMBA treated MEL cells clearly showed temporal changes for the time intervals studied. The results provide further evidence for the existence of oscillations, consistent with our earlier studies relating to protein phosphorylation and the expression of kinases and phosphatases, and to the expression of other key proteins in these and HL60 (human promyelocytic leukaemia) cells (Bhoola and Hammond, 2000;Hammond, 2002, 2003;Ferreira et al, 1994b;Hammond et al, 1985Hammond et al, , 1989Hammond et al, , 1998Hammond et al, , 2000a.…”

Section: Methodssupporting

confidence: 90%

Temporal changes in the expression of protein phosphatase 1 and protein phosphatase 2A in proliferating and differentiating murine erythroleukaemia cells

Bodalina

Hammond

Gilbert³

2005

Cell Biology International

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Rhythmic changes in the expression of protein phosphatase 1 (PP1) and protein phosphatase 2A (PP2A) were investigated during hexamethylene bisacetamide (HMBA) induced differentiation of murine erythroleukaemic (MEL) cells. Cell extracts were analysed by SDS-PAGE and western immunoblotting using specific antibodies. An immunospecific band of molecular mass 36 kDa (catalytic subunit) was detected for PP1. For PP2A, two immunospecific bands of 32 kDa (proteolytically cleaved catalytic subunit) and 36 kDa (catalytic subunit) were observed. Comparisons of proliferating and differentiating cells using only one time point showed no significant differences between mean values for the expression of the PP1 or PP2A enzyme proteins. This kind of analysis, implying that HMBA had little effect, proved misleading, as comparisons using multiple time points showed rhythmic patterns of protein expression which were modulated by the differentiating agent. The effects were complex affecting both the frequency and phasing of rhythms. The results add further support for the view that live cells are multi-oscillators and for the concept that differentiation depends on changes in temporal organization of complex autodynamic feedback loops and multiple interactions between control circuits performing in parallel. In particular, modulation of the dynamics of key proteins, such as PP1 and PP2A, may be a possible mechanism for controlling cellular function and reversing transformation in accordance with long standing theoretical and other experimental data.

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Section: Methodssupporting

confidence: 90%

Temporal changes in the expression of protein phosphatase 1 and protein phosphatase 2A in proliferating and differentiating murine erythroleukaemia cells

Bodalina

Hammond

Gilbert³

2005

Cell Biology International

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“…The following step is alteration of the activity of calcium-dependent protein kinases and, therewith, protein phosphorylation, as was shown in some studies (Goldering et al, 1985;Kreutter et al, 1987;Chan, 1989;Yates et al, 1989;Yu et al, 1994;Berrie and Cobbold, 1995;Nagai, 1995;Ferrari et al, 1995;Arakane et al, 1995). Some stages of the synchronization of oscillations of the protein metabolism have been recently described in studies of the kinetics of protein kinases and phosphorylation (Ferreira et al, 1994;Hammond et al, 1998;Calvert-Evers and Hammond, 2000;Bhoola and Hammond, 2000).…”

Section: Resultsmentioning

confidence: 81%

Age-related features of protein synthesis rhythm. Effects of extracellular medium

et al. 2005

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Circahoralian, or ultradian, intracellular rhythms, including protein synthesis rhythm, were described in various cells both in situ and in vitro (for reviews see Brodsky, 1975; Ultradian Rhythms …, 1992). They have been studied for a long time in the cultures of hepatocytes as well. Visualization of any rhythm in a cell culture is only possible when oscillations are synchronized due to intercellular cooperation. The rhythm expression depends on the degree of synchrony, i.e., on cooperative activity of cell in the formation of an aggregate rhythm of a cell population. The amplitude of rhythm, or range of oscillations, is a visible reflection of this cooperation. In the case when each individual cell has a rhythm, but oscillations in different cells are antiphasic, the aggregate kinetics of a population will not be oscillatory. When the phases of oscillations correspond to each other, a rhythm is visualized and, the closer the phases of oscillations of individual cells, the higher the amplitude of the aggregate rhythm.We have already shown that the amplitude of oscillations of protein synthesis intensity in the cultures of hepatocytes from old rats is lower than that from young animals (Brodsky et al. , 2001), which characterized a low cooperative activity of the cells of old animals. However, these data were preliminary: we assayed the kinetics of protein synthesis only in two old rats. In order to confirm the first observations, it was necessary to carry out experiments of a larger material and, in case of a positive result, clarify possible causes of agerelated changes and establish to what extent they are reversible.When studying intercellular cooperation, we investigated dense, fast self-synchronizing in a fresh medium, hepatocytes and sparse asynchronous cultures (Brodsky et al. , 1994(Brodsky et al. , , 1996a. We used the synchronizers we found earlier: gangliosides (Brodsky et al. , 1996a(Brodsky et al. , , 1997Zvezdina et al. , 2000). Gangliosides are cell membrane glycolipids; they are constantly secreted in extracellular medium and incorporated in other cells and affect many intracellular processes (for reviews see Hakomori, 1981Hakomori, , 2000Tettamanti and Riboni, 1994;Yates and Rampersaud, 1998). In our experiments, asynchronous sparse cultures of hepatocytes were synchronized soon after addition of a standard mix of bovine brain gangliosides (BBG: 20% GM1, 40% GD1a, 16% GD1b, and ca. 4% of others) or individual fractions (GM1 or GD1a). The synchronizing effect of gangliosides can be reproduced by a medium conditioned by dense cultures (Brodsky et al. , 1995(Brodsky et al. , , 2000b.In order to simulate the influence of gangliosides on intracellular processes, we studied their well known effect on the concentration of calcium ions in the cytoAbstract -Cell interactions have been studied in cultures pf hepatocytes from young and old rats. The rhythm of protein synthesis is an index of cell interaction and synchronization in culture, while the amplitude of oscillations characterized cell cooperation i...

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“…Protein phosphorylation can be a crucial factor in the organization of some ultradian rhythms (enzyme activity, protein content, etc.) has been shown by the Gilbert and Hammond group (Ferreira et al, 1994;Calvert-Evers and Hammond, 2000;Bhoola and Hammond, 2000). In other work, melatonin activated protein kinase C activity and influences the organization of the cytoskeleton by the phosphorylation of proteins (Benitez-King, 2000Tepperman et al, 2005).…”

Section: Melatonin As a Synchronizer Of Protein Synthesis Oscillationmentioning

confidence: 85%

Melatonin as the most effective organizer of the rhythm of protein synthesis in hepatocytes in vitro and in vivo

Brodsky

Zvezdina

2010

Cell Biology International

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Recent data has extended a large array of melatonin functions by the discovery of melatonin's involvement in the organization and regulation of the rhythm of intracellular protein synthesis. An ultradian rhythm in total protein synthesis has been detected in primary hepatocyte cultures 5 min after addition of 1-5 nM melatonin to the medium. The melatonin effect was mediated via its receptors (as shown in experiments with luzindole), leading to the cell synchronization as well as the mean rate of protein synthesis rate being increased. The chain of processes synchronizing the oscillation of the rate protein synthesis throughout the hepatocyte population includes Ca²+ fluxes {experiments with BAPTA-AM [1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (acetomethyl ester)]}. Inhibition of protein kinase activity (experiments with H7) inhibited the synchronizing function of melatonin. Activation of protein kinase activity results in a shift of the protein synthesis oscillation; the effect was the same as melatonin added to the culture medium. In another series of experiments, after melatonin was intraperitoneally injected to rat (0.015-0.020 μg/kg), hepatocytes were isolated and cultures established. A synchronizing effect of melatonin in vivo was detected as early as in the estimates from the direct action of melatonin on cell cultures. In the cultures obtained from old rats provided with melatonin, the amplitude of protein synthesis rhythm was enhanced, i.e. cell-cell interactions were increased, as well as rate of the protein synthesis being enhanced.

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Insulin stimulation of high frequency phosphorylation dynamics in murine erythroleukemia cells

Cited by 23 publications

References 17 publications

Temporal changes in the expression of protein phosphatase 1 and protein phosphatase 2A in proliferating and differentiating murine erythroleukaemia cells

Temporal changes in the expression of protein phosphatase 1 and protein phosphatase 2A in proliferating and differentiating murine erythroleukaemia cells

Age-related features of protein synthesis rhythm. Effects of extracellular medium

Melatonin as the most effective organizer of the rhythm of protein synthesis in hepatocytes in vitro and in vivo

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