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...
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1994
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| Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_01475975_v18_n4_p330_Zelada http://hdl.handle.net/20.500.12110/paper_01475975_v18_n4_p330_Zelada |
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paper:paper_01475975_v18_n4_p330_Zelada2023-06-08T15:12:46Z Occurrence of GTP-binding proteins in the ascomycete Saccobolus platensis 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. 1994 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_01475975_v18_n4_p330_Zelada 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 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. |
| 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 |
| publishDate |
1994 |
| url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_01475975_v18_n4_p330_Zelada http://hdl.handle.net/20.500.12110/paper_01475975_v18_n4_p330_Zelada |
| _version_ |
1768546717699932160 |