Cargando…

ProSAAS-Derived Peptides Are Differentially Processed and Sorted in Mouse Brain and AtT-20 Cells

ProSAAS is the precursor for some of the most abundant peptides found in mouse brain and other tissues, including peptides named SAAS, PEN, and LEN. Both SAAS and LEN are found in big and little forms due to differential processing. Initial processing of proSAAS is mediated by furin (and/or furin-li...

Descripción completa

Detalles Bibliográficos
Autores principales: Wardman, Jonathan H., Fricker, Lloyd D.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Public Library of Science 2014
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4141687/
https://www.ncbi.nlm.nih.gov/pubmed/25148519
http://dx.doi.org/10.1371/journal.pone.0104232
_version_ 1782331672258150400
author Wardman, Jonathan H.
Fricker, Lloyd D.
author_facet Wardman, Jonathan H.
Fricker, Lloyd D.
author_sort Wardman, Jonathan H.
collection PubMed
description ProSAAS is the precursor for some of the most abundant peptides found in mouse brain and other tissues, including peptides named SAAS, PEN, and LEN. Both SAAS and LEN are found in big and little forms due to differential processing. Initial processing of proSAAS is mediated by furin (and/or furin-like enzymes) and carboxypeptidase D, while the smaller forms are generated by secretory granule prohormone convertases and carboxypeptidase E. In mouse hypothalamus, PEN and big LEN colocalize with neuropeptide Y. In the present study, little LEN and SAAS were detected in mouse hypothalamus but not in cell bodies of neuropeptide Y-expressing neurons. PEN and big LEN show substantial colocalization in hypothalamus, but big LEN and little LEN do not. An antiserum to SAAS that detects both big and little forms of this peptide did not show substantial colocalization with PEN or big LEN. To further study this, the AtT-20 cells mouse pituitary corticotrophic cell line was transfected with rat proSAAS and the distribution of peptides examined. As found in mouse hypothalamus, only some of the proSAAS-derived peptides colocalized with each other in AtT-20 cells. The two sites within proSAAS that are known to be efficiently cleaved by furin were altered by site-directed mutagenesis to convert the P4 Arg into Lys; this change converts the sequences from furin consensus sites into prohormone convertase consensus sites. Upon expression of the mutated form of proSAAS in AtT-20 cells, there was significantly more colocalization of proSAAS-derived peptides PEN and SAAS. Taken together, these results indicate that proSAAS is initially cleaved in the Golgi or trans-Golgi network by furin and/or furin-like enzymes and the resulting fragments are sorted into distinct vesicles and further processed by additional enzymes into the mature peptides.
format Online
Article
Text
id pubmed-4141687
institution National Center for Biotechnology Information
language English
publishDate 2014
publisher Public Library of Science
record_format MEDLINE/PubMed
spelling pubmed-41416872014-08-25 ProSAAS-Derived Peptides Are Differentially Processed and Sorted in Mouse Brain and AtT-20 Cells Wardman, Jonathan H. Fricker, Lloyd D. PLoS One Research Article ProSAAS is the precursor for some of the most abundant peptides found in mouse brain and other tissues, including peptides named SAAS, PEN, and LEN. Both SAAS and LEN are found in big and little forms due to differential processing. Initial processing of proSAAS is mediated by furin (and/or furin-like enzymes) and carboxypeptidase D, while the smaller forms are generated by secretory granule prohormone convertases and carboxypeptidase E. In mouse hypothalamus, PEN and big LEN colocalize with neuropeptide Y. In the present study, little LEN and SAAS were detected in mouse hypothalamus but not in cell bodies of neuropeptide Y-expressing neurons. PEN and big LEN show substantial colocalization in hypothalamus, but big LEN and little LEN do not. An antiserum to SAAS that detects both big and little forms of this peptide did not show substantial colocalization with PEN or big LEN. To further study this, the AtT-20 cells mouse pituitary corticotrophic cell line was transfected with rat proSAAS and the distribution of peptides examined. As found in mouse hypothalamus, only some of the proSAAS-derived peptides colocalized with each other in AtT-20 cells. The two sites within proSAAS that are known to be efficiently cleaved by furin were altered by site-directed mutagenesis to convert the P4 Arg into Lys; this change converts the sequences from furin consensus sites into prohormone convertase consensus sites. Upon expression of the mutated form of proSAAS in AtT-20 cells, there was significantly more colocalization of proSAAS-derived peptides PEN and SAAS. Taken together, these results indicate that proSAAS is initially cleaved in the Golgi or trans-Golgi network by furin and/or furin-like enzymes and the resulting fragments are sorted into distinct vesicles and further processed by additional enzymes into the mature peptides. Public Library of Science 2014-08-22 /pmc/articles/PMC4141687/ /pubmed/25148519 http://dx.doi.org/10.1371/journal.pone.0104232 Text en © 2014 Wardman, Fricker http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited.
spellingShingle Research Article
Wardman, Jonathan H.
Fricker, Lloyd D.
ProSAAS-Derived Peptides Are Differentially Processed and Sorted in Mouse Brain and AtT-20 Cells
title ProSAAS-Derived Peptides Are Differentially Processed and Sorted in Mouse Brain and AtT-20 Cells
title_full ProSAAS-Derived Peptides Are Differentially Processed and Sorted in Mouse Brain and AtT-20 Cells
title_fullStr ProSAAS-Derived Peptides Are Differentially Processed and Sorted in Mouse Brain and AtT-20 Cells
title_full_unstemmed ProSAAS-Derived Peptides Are Differentially Processed and Sorted in Mouse Brain and AtT-20 Cells
title_short ProSAAS-Derived Peptides Are Differentially Processed and Sorted in Mouse Brain and AtT-20 Cells
title_sort prosaas-derived peptides are differentially processed and sorted in mouse brain and att-20 cells
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4141687/
https://www.ncbi.nlm.nih.gov/pubmed/25148519
http://dx.doi.org/10.1371/journal.pone.0104232
work_keys_str_mv AT wardmanjonathanh prosaasderivedpeptidesaredifferentiallyprocessedandsortedinmousebrainandatt20cells
AT frickerlloydd prosaasderivedpeptidesaredifferentiallyprocessedandsortedinmousebrainandatt20cells