<named-content content-type="genus-species">Escherichia coli</named-content> SRP, Its Protein Subunit Ffh, and the Ffh M Domain Are Able To Selectively Limit Membrane Protein Expression When Overexpressed

ABSTRACT The Escherichia coli signal recognition particle (SRP) system plays an important role in membrane protein biogenesis. Previous studies have suggested indirectly that in addition to its role during the targeting of ribosomes translating membrane proteins to translocons, the SRP might also ha...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	Ido Yosef, Elena S. Bochkareva, Eitan Bibi
Formato:	article
Lenguaje:	EN
Publicado:	American Society for Microbiology 2010
Materias:	Microbiology QR1-502
Acceso en línea:	https://doaj.org/article/6cce861069d9431db3be6a36ad1e1510
Etiquetas:	Agregar Etiqueta Sin Etiquetas, Sea el primero en etiquetar este registro!

id	oai:doaj.org-article:6cce861069d9431db3be6a36ad1e1510
record_format	dspace
spelling	oai:doaj.org-article:6cce861069d9431db3be6a36ad1e15102021-11-15T15:38:12Z<named-content content-type="genus-species">Escherichia coli</named-content> SRP, Its Protein Subunit Ffh, and the Ffh M Domain Are Able To Selectively Limit Membrane Protein Expression When Overexpressed10.1128/mBio.00020-102150-7511https://doaj.org/article/6cce861069d9431db3be6a36ad1e15102010-06-01T00:00:00Zhttps://journals.asm.org/doi/10.1128/mBio.00020-10https://doaj.org/toc/2150-7511ABSTRACT The Escherichia coli signal recognition particle (SRP) system plays an important role in membrane protein biogenesis. Previous studies have suggested indirectly that in addition to its role during the targeting of ribosomes translating membrane proteins to translocons, the SRP might also have a quality control role in preventing premature synthesis of membrane proteins in the cytoplasm. This proposal was studied here using cells simultaneously overexpressing various membrane proteins and either SRP, the SRP protein Ffh, its 4.5S RNA, or the Ffh M domain. The results show that SRP, Ffh, and the M domain are all able to selectively inhibit the expression of membrane proteins. We observed no apparent changes in the steady-state mRNA levels or membrane protein stability, suggesting that inhibition may occur at the level of translation, possibly through the interaction between Ffh and ribosome-hydrophobic nascent chain complexes. Since E. coli SRP does not have a eukaryote-like translation arrest domain, we discuss other possible mechanisms by which this SRP might regulate membrane protein translation when overexpressed. IMPORTANCE The eukaryotic SRP slows down translation of SRP substrates by cytoplasmic ribosomes. This activity is important for preventing premature synthesis of secretory and membrane proteins in the cytoplasm. It is likely that an analogous quality control step would be required in all living cells. However, on the basis of its composition and domain structure and limited in vitro studies, it is believed that the E. coli SRP is unable to regulate ribosomes translating membrane proteins. Nevertheless, several in vivo studies have suggested otherwise. To address this issue further in vivo, we utilized unbalanced conditions under which E. coli simultaneously overexpresses SRP and each of several membrane or cytosolic proteins. Surprisingly, our results clearly show that the E. coli SRP is capable of regulating membrane protein synthesis and demonstrate that the M domain of Ffh mediates this activity. These results thus open the way for mechanistic characterization of this quality control process in bacteria.Ido YosefElena S. BochkarevaEitan BibiAmerican Society for MicrobiologyarticleMicrobiologyQR1-502ENmBio, Vol 1, Iss 2 (2010)
institution	DOAJ
collection	DOAJ
language	EN
topic	Microbiology QR1-502
spellingShingle	Microbiology QR1-502 Ido Yosef Elena S. Bochkareva Eitan Bibi <named-content content-type="genus-species">Escherichia coli</named-content> SRP, Its Protein Subunit Ffh, and the Ffh M Domain Are Able To Selectively Limit Membrane Protein Expression When Overexpressed
description	ABSTRACT The Escherichia coli signal recognition particle (SRP) system plays an important role in membrane protein biogenesis. Previous studies have suggested indirectly that in addition to its role during the targeting of ribosomes translating membrane proteins to translocons, the SRP might also have a quality control role in preventing premature synthesis of membrane proteins in the cytoplasm. This proposal was studied here using cells simultaneously overexpressing various membrane proteins and either SRP, the SRP protein Ffh, its 4.5S RNA, or the Ffh M domain. The results show that SRP, Ffh, and the M domain are all able to selectively inhibit the expression of membrane proteins. We observed no apparent changes in the steady-state mRNA levels or membrane protein stability, suggesting that inhibition may occur at the level of translation, possibly through the interaction between Ffh and ribosome-hydrophobic nascent chain complexes. Since E. coli SRP does not have a eukaryote-like translation arrest domain, we discuss other possible mechanisms by which this SRP might regulate membrane protein translation when overexpressed. IMPORTANCE The eukaryotic SRP slows down translation of SRP substrates by cytoplasmic ribosomes. This activity is important for preventing premature synthesis of secretory and membrane proteins in the cytoplasm. It is likely that an analogous quality control step would be required in all living cells. However, on the basis of its composition and domain structure and limited in vitro studies, it is believed that the E. coli SRP is unable to regulate ribosomes translating membrane proteins. Nevertheless, several in vivo studies have suggested otherwise. To address this issue further in vivo, we utilized unbalanced conditions under which E. coli simultaneously overexpresses SRP and each of several membrane or cytosolic proteins. Surprisingly, our results clearly show that the E. coli SRP is capable of regulating membrane protein synthesis and demonstrate that the M domain of Ffh mediates this activity. These results thus open the way for mechanistic characterization of this quality control process in bacteria.
format	article
author	Ido Yosef Elena S. Bochkareva Eitan Bibi
author_facet	Ido Yosef Elena S. Bochkareva Eitan Bibi
author_sort	Ido Yosef
title	<named-content content-type="genus-species">Escherichia coli</named-content> SRP, Its Protein Subunit Ffh, and the Ffh M Domain Are Able To Selectively Limit Membrane Protein Expression When Overexpressed
title_short	<named-content content-type="genus-species">Escherichia coli</named-content> SRP, Its Protein Subunit Ffh, and the Ffh M Domain Are Able To Selectively Limit Membrane Protein Expression When Overexpressed
title_full	<named-content content-type="genus-species">Escherichia coli</named-content> SRP, Its Protein Subunit Ffh, and the Ffh M Domain Are Able To Selectively Limit Membrane Protein Expression When Overexpressed
title_fullStr	<named-content content-type="genus-species">Escherichia coli</named-content> SRP, Its Protein Subunit Ffh, and the Ffh M Domain Are Able To Selectively Limit Membrane Protein Expression When Overexpressed
title_full_unstemmed	<named-content content-type="genus-species">Escherichia coli</named-content> SRP, Its Protein Subunit Ffh, and the Ffh M Domain Are Able To Selectively Limit Membrane Protein Expression When Overexpressed
title_sort	<named-content content-type="genus-species">escherichia coli</named-content> srp, its protein subunit ffh, and the ffh m domain are able to selectively limit membrane protein expression when overexpressed
publisher	American Society for Microbiology
publishDate	2010
url	https://doaj.org/article/6cce861069d9431db3be6a36ad1e1510
work_keys_str_mv	AT idoyosef namedcontentcontenttypegenusspeciesescherichiacolinamedcontentsrpitsproteinsubunitffhandtheffhmdomainareabletoselectivelylimitmembraneproteinexpressionwhenoverexpressed AT elenasbochkareva namedcontentcontenttypegenusspeciesescherichiacolinamedcontentsrpitsproteinsubunitffhandtheffhmdomainareabletoselectivelylimitmembraneproteinexpressionwhenoverexpressed AT eitanbibi namedcontentcontenttypegenusspeciesescherichiacolinamedcontentsrpitsproteinsubunitffhandtheffhmdomainareabletoselectivelylimitmembraneproteinexpressionwhenoverexpressed
_version_	1718427829739192320

<named-content content-type="genus-species">Escherichia coli</named-content> SRP, Its Protein Subunit Ffh, and the Ffh M Domain Are Able To Selectively Limit Membrane Protein Expression When Overexpressed

Ejemplares similares