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How is the balance between protein synthesis and degradation achieved?

Rothman S - Theor Biol Med Model (2010)

Bottom Line: Unlike most substances that cells manufacture, proteins are not produced and broken down by a common series of chemical reactions, but by completely different (independent and disconnected) mechanisms that possess no intrinsic means of making the rates of the two processes equal and attaining steady state concentrations.Balance between them is achieved extrinsically and is often imagined today to be the result of the actions of chemical feedback agents.Those "other means" necessarily involve reversible mass action or equilibrium-based interactions between native and altered forms of protein molecules somewhere in time and space between their synthesis and degradation.

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Affiliation: University of California, San Francisco, San Francisco, CA 94143, USA. stephen.rothman@ucsf.edu

ABSTRACT
Unlike most substances that cells manufacture, proteins are not produced and broken down by a common series of chemical reactions, but by completely different (independent and disconnected) mechanisms that possess no intrinsic means of making the rates of the two processes equal and attaining steady state concentrations. Balance between them is achieved extrinsically and is often imagined today to be the result of the actions of chemical feedback agents. But however instantiated, chemical feedback or any similar mechanism can only rectify induced imbalances in a system previously balanced by other means. Those "other means" necessarily involve reversible mass action or equilibrium-based interactions between native and altered forms of protein molecules somewhere in time and space between their synthesis and degradation.

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The feedback regulation of protein synthesis. Shown are events of protein synthesis that are affected either directly or indirectly by feedback agents (italics)(see The effect of feedback).
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Figure 1: The feedback regulation of protein synthesis. Shown are events of protein synthesis that are affected either directly or indirectly by feedback agents (italics)(see The effect of feedback).

Mentions: If the mechanisms that determine the rate at which a protein is made and those that determine the rate at which it is broken down possess no intrinsic means of making the two equal, then balance between them requires a mechanism that is extrinsic to these processes. As said, this is usually, though not uniformly, imagined today in terms of chemical feedback. Chemical agents or signals, acting separately or together, synergistically or antagonistically, on one process or both, feedback on various steps in synthetic and degradative pathways adjusting their rates to achieve metabolic balance (figures 1 and 2)[1,2].


How is the balance between protein synthesis and degradation achieved?

Rothman S - Theor Biol Med Model (2010)

The feedback regulation of protein synthesis. Shown are events of protein synthesis that are affected either directly or indirectly by feedback agents (italics)(see The effect of feedback).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2909984&req=5

Figure 1: The feedback regulation of protein synthesis. Shown are events of protein synthesis that are affected either directly or indirectly by feedback agents (italics)(see The effect of feedback).
Mentions: If the mechanisms that determine the rate at which a protein is made and those that determine the rate at which it is broken down possess no intrinsic means of making the two equal, then balance between them requires a mechanism that is extrinsic to these processes. As said, this is usually, though not uniformly, imagined today in terms of chemical feedback. Chemical agents or signals, acting separately or together, synergistically or antagonistically, on one process or both, feedback on various steps in synthetic and degradative pathways adjusting their rates to achieve metabolic balance (figures 1 and 2)[1,2].

Bottom Line: Unlike most substances that cells manufacture, proteins are not produced and broken down by a common series of chemical reactions, but by completely different (independent and disconnected) mechanisms that possess no intrinsic means of making the rates of the two processes equal and attaining steady state concentrations.Balance between them is achieved extrinsically and is often imagined today to be the result of the actions of chemical feedback agents.Those "other means" necessarily involve reversible mass action or equilibrium-based interactions between native and altered forms of protein molecules somewhere in time and space between their synthesis and degradation.

View Article: PubMed Central - HTML - PubMed

Affiliation: University of California, San Francisco, San Francisco, CA 94143, USA. stephen.rothman@ucsf.edu

ABSTRACT
Unlike most substances that cells manufacture, proteins are not produced and broken down by a common series of chemical reactions, but by completely different (independent and disconnected) mechanisms that possess no intrinsic means of making the rates of the two processes equal and attaining steady state concentrations. Balance between them is achieved extrinsically and is often imagined today to be the result of the actions of chemical feedback agents. But however instantiated, chemical feedback or any similar mechanism can only rectify induced imbalances in a system previously balanced by other means. Those "other means" necessarily involve reversible mass action or equilibrium-based interactions between native and altered forms of protein molecules somewhere in time and space between their synthesis and degradation.

Show MeSH
Related in: MedlinePlus