A protein precursor, also called a pro-protein or pro-peptide, is an inactive protein (or peptide) that can be turned into an active form by post-translational modification, such as breaking off a piece of the molecule or adding on another molecule. The name of the precursor for a protein is often prefixed by pro-. Examples include proinsulin and proopiomelanocortin, which are both prohormones.
Protein precursors are often used by an organism when the subsequent protein is potentially harmful, but needs to be available on short notice and/or in large quantities. Enzyme precursors are called zymogens or proenzymes. Examples are enzymes of the digestive tract in humans.
Some protein precursors are secreted from the cell. Many of these are synthesized with an N-terminal signal peptide that targets them for secretion. Like other proteins that contain a signal peptide, their name is prefixed by pre. They are thus called pre-pro-proteins or pre-pro-peptides.[1] The signal peptide is cleaved off in the endoplasmic reticulum.[1] An example is preproinsulin.
Pro-sequences are areas in the protein that are essential for its correct folding, usually in the transition of a protein from an inactive to an active state. Pro-sequences may also be involved in pro-protein transport and secretion.[2]
Pro-domain (or prodomain) is the domain of a proprotein.
Referencesedit
^ abAlberts, Bruce (2002). Molecular biology of the cell. New York: Garland Science. p. 760. ISBN0-8153-3218-1.
^Eder J, Fersht AR (May 1995). "Pro-sequence-assisted protein folding". Mol. Microbiol. 16 (4): 609–14. doi:10.1111/j.1365-2958.1995.tb02423.x. PMID 7476156.
External linksedit
Media related to Precursor proteins at Wikimedia Commons
This protein-related article is a stub. You can help Wikipedia by expanding it.
protein, precursor, protein, precursor, also, called, protein, peptide, inactive, protein, peptide, that, turned, into, active, form, post, translational, modification, such, breaking, piece, molecule, adding, another, molecule, name, precursor, protein, often. A protein precursor also called a pro protein or pro peptide is an inactive protein or peptide that can be turned into an active form by post translational modification such as breaking off a piece of the molecule or adding on another molecule The name of the precursor for a protein is often prefixed by pro Examples include proinsulin and proopiomelanocortin which are both prohormones Protein precursors are often used by an organism when the subsequent protein is potentially harmful but needs to be available on short notice and or in large quantities Enzyme precursors are called zymogens or proenzymes Examples are enzymes of the digestive tract in humans Some protein precursors are secreted from the cell Many of these are synthesized with an N terminal signal peptide that targets them for secretion Like other proteins that contain a signal peptide their name is prefixed by pre They are thus called pre pro proteins or pre pro peptides 1 The signal peptide is cleaved off in the endoplasmic reticulum 1 An example is preproinsulin Pro sequences are areas in the protein that are essential for its correct folding usually in the transition of a protein from an inactive to an active state Pro sequences may also be involved in pro protein transport and secretion 2 Pro domain or prodomain is the domain of a proprotein References edit a b Alberts Bruce 2002 Molecular biology of the cell New York Garland Science p 760 ISBN 0 8153 3218 1 Eder J Fersht AR May 1995 Pro sequence assisted protein folding Mol Microbiol 16 4 609 14 doi 10 1111 j 1365 2958 1995 tb02423 x PMID 7476156 External links edit nbsp Media related to Precursor proteins at Wikimedia Commons nbsp This protein related article is a stub You can help Wikipedia by expanding it vte Retrieved from https en wikipedia org w index php title Protein precursor amp oldid 997716466, wikipedia, wiki, book, books, library,
