Occurrence of GTP-binding proteins in the ascomycete Saccobolus platensis

We have previously shown that in the ascomycete Saccobolus platensis the presence of cyclic AMP can overcome the requirement for light to produce apothecia. With the aim to gain insight into the phototransduction mechanism the existence of G protein-like molecules was investigated. By using the GTP...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Zelada, A.M., Samela, A., Passeron, S., Cantors, M.L.
Formato: JOUR
Materias:
Acceso en línea:http://hdl.handle.net/20.500.12110/paper_01475975_v18_n4_p330_Zelada
Aporte de:
id todo:paper_01475975_v18_n4_p330_Zelada
record_format dspace
spelling todo:paper_01475975_v18_n4_p330_Zelada2023-10-03T15:00:33Z Occurrence of GTP-binding proteins in the ascomycete Saccobolus platensis Zelada, A.M. Samela, A. Passeron, S. Cantors, M.L. ascomycete GTP-binding proteins photodifferentiation Saccobolus platensis adenosine triphosphate cholera toxin guanine nucleotide binding protein guanosine triphosphate protein subunit sulfur 35 article Ascomycetes binding competition dissociation constant immunoblotting membrane binding nonhuman polyacrylamide gel electrophoresis priority journal Ascomycota Mammalia Saccobolus Vertebrata We have previously shown that in the ascomycete Saccobolus platensis the presence of cyclic AMP can overcome the requirement for light to produce apothecia. With the aim to gain insight into the phototransduction mechanism the existence of G protein-like molecules was investigated. By using the GTP analog [35S]GTP-γS we detected the existence of GTP-binding proteins; the dissociation constant for the binding of the nucleotide was calculated (Kd = 52 nM); the binding was effectively competed by GTP and GDPPS and to a lesser extent by ATP. We also demonstrated by SDS-PAGE the existence of proteins of 48, 41, 26, and 15 kDa that are substrates of the cholera toxin-dependent ADP-ribosylation reaction. Proteins resolved by SDS-PAGE were identified by Western blotting with antisera specific for vertebrate G protein subunits; the antibody anti-αcommon revealed two main bands at 48 and 41 kDa; the AS/7 antibody (anti-αt, −α1, and −ai2) led to the identification of one band at 41 kDa; the antibody anti-β subunit revealed a polipeptide band at around 37 kDa. The antibody anti-αcommon also abolished the binding of [35S]GTP-γS to crude membranes. The results presented in this paper provide evidence for the existence in S. platensis of proteins that proved to have a behavior similar to that of mammalian G proteins. © 1994, Academic Press, Inc.. All rights reserved. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_01475975_v18_n4_p330_Zelada
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic ascomycete
GTP-binding proteins
photodifferentiation
Saccobolus platensis
adenosine triphosphate
cholera toxin
guanine nucleotide binding protein
guanosine triphosphate
protein subunit
sulfur 35
article
Ascomycetes
binding competition
dissociation constant
immunoblotting
membrane binding
nonhuman
polyacrylamide gel electrophoresis
priority journal
Ascomycota
Mammalia
Saccobolus
Vertebrata
spellingShingle ascomycete
GTP-binding proteins
photodifferentiation
Saccobolus platensis
adenosine triphosphate
cholera toxin
guanine nucleotide binding protein
guanosine triphosphate
protein subunit
sulfur 35
article
Ascomycetes
binding competition
dissociation constant
immunoblotting
membrane binding
nonhuman
polyacrylamide gel electrophoresis
priority journal
Ascomycota
Mammalia
Saccobolus
Vertebrata
Zelada, A.M.
Samela, A.
Passeron, S.
Cantors, M.L.
Occurrence of GTP-binding proteins in the ascomycete Saccobolus platensis
topic_facet ascomycete
GTP-binding proteins
photodifferentiation
Saccobolus platensis
adenosine triphosphate
cholera toxin
guanine nucleotide binding protein
guanosine triphosphate
protein subunit
sulfur 35
article
Ascomycetes
binding competition
dissociation constant
immunoblotting
membrane binding
nonhuman
polyacrylamide gel electrophoresis
priority journal
Ascomycota
Mammalia
Saccobolus
Vertebrata
description We have previously shown that in the ascomycete Saccobolus platensis the presence of cyclic AMP can overcome the requirement for light to produce apothecia. With the aim to gain insight into the phototransduction mechanism the existence of G protein-like molecules was investigated. By using the GTP analog [35S]GTP-γS we detected the existence of GTP-binding proteins; the dissociation constant for the binding of the nucleotide was calculated (Kd = 52 nM); the binding was effectively competed by GTP and GDPPS and to a lesser extent by ATP. We also demonstrated by SDS-PAGE the existence of proteins of 48, 41, 26, and 15 kDa that are substrates of the cholera toxin-dependent ADP-ribosylation reaction. Proteins resolved by SDS-PAGE were identified by Western blotting with antisera specific for vertebrate G protein subunits; the antibody anti-αcommon revealed two main bands at 48 and 41 kDa; the AS/7 antibody (anti-αt, −α1, and −ai2) led to the identification of one band at 41 kDa; the antibody anti-β subunit revealed a polipeptide band at around 37 kDa. The antibody anti-αcommon also abolished the binding of [35S]GTP-γS to crude membranes. The results presented in this paper provide evidence for the existence in S. platensis of proteins that proved to have a behavior similar to that of mammalian G proteins. © 1994, Academic Press, Inc.. All rights reserved.
format JOUR
author Zelada, A.M.
Samela, A.
Passeron, S.
Cantors, M.L.
author_facet Zelada, A.M.
Samela, A.
Passeron, S.
Cantors, M.L.
author_sort Zelada, A.M.
title Occurrence of GTP-binding proteins in the ascomycete Saccobolus platensis
title_short Occurrence of GTP-binding proteins in the ascomycete Saccobolus platensis
title_full Occurrence of GTP-binding proteins in the ascomycete Saccobolus platensis
title_fullStr Occurrence of GTP-binding proteins in the ascomycete Saccobolus platensis
title_full_unstemmed Occurrence of GTP-binding proteins in the ascomycete Saccobolus platensis
title_sort occurrence of gtp-binding proteins in the ascomycete saccobolus platensis
url http://hdl.handle.net/20.500.12110/paper_01475975_v18_n4_p330_Zelada
work_keys_str_mv AT zeladaam occurrenceofgtpbindingproteinsintheascomycetesaccobolusplatensis
AT samelaa occurrenceofgtpbindingproteinsintheascomycetesaccobolusplatensis
AT passerons occurrenceofgtpbindingproteinsintheascomycetesaccobolusplatensis
AT cantorsml occurrenceofgtpbindingproteinsintheascomycetesaccobolusplatensis
_version_ 1807319167257280512