A novel GTP-binding protein, Sar1p, is involved in transport from the endoplasmic reticulum to the Golgi apparatus.
Akihiko Nakano,M Muramatsu +1 more
TLDR
It is proposed that Sec12p and Sarlp collaborate in directing ER-Golgi protein transport andGene disruption experiments show that SAR1 is essential for cell growth.Abstract:
SAR1, a gene that has been isolated as a multicopy suppressor of the yeast ER-Golgi transport mutant sec12, encodes a novel GTP-binding protein. Its nucleotide sequence predicts a 21-kD polypeptide that contains amino acid sequences highly homologous to GTP-binding domains of many ras-related proteins. Gene disruption experiments show that SAR1 is essential for cell growth. To test its function further, SAR1 has been placed under control of the GAL1 promoter and introduced into a haploid cell that had its chromosomal SAR1 copy disrupted. This mutant grows normally in galactose medium but arrests growth 12-15 h after transfer to glucose medium. At the same time, mutant cells accumulate ER precursor forms of a secretory pheromone, alpha-mating factor, and a vacuolar enzyme, carboxypeptidase Y. We propose that Sec12p and Sarlp collaborate in directing ER-Golgi protein transport.read more
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The GTPase superfamily: conserved structure and molecular mechanism
TL;DR: GTPases are conserved molecular switches, built according to a common structural design, and rapidly accruing knowledge of individual GTPases—crystal structures, biochemical properties, or results of molecular genetic experiments—support and generate hypotheses relating structure to function in other members of the diverse family of GTPase.
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Small GTP-Binding Proteins
TL;DR: In this review, functions of small G proteins and their modes of activation and action are described.
Journal ArticleDOI
The small GTPase rab5 functions as a regulatory factor in the early endocytic pathway.
Cecilia Bucci,Robert G. Parton,Ian H. Mather,Henk Stunnenberg,Kai Simons,Bernard Hoflack,Marino Zerial +6 more
TL;DR: It is concluded that rab5 is a rate-limiting component of the machinery regulating the kinetics of membrane traffic in the early endocytic pathway.
Journal ArticleDOI
COPII: a membrane coat formed by Sec proteins that drive vesicle budding from the endoplasmic reticulum.
Charles Barlowe,Lelio Orci,Tom Yeung,Midori Hosobuchi,Susan Hamamoto,Nina R. Salama,M F Rexach,Mariella Ravazzola,Mylène Amherdt,Randy Schekman +9 more
TL;DR: In vitro synthesis of endoplasmic reticulum-derived transport vesicles has been reconstituted with washed membranes and three soluble proteins and it is proposed that the coat structures be called COPI and COPII.
Journal ArticleDOI
Localization of low molecular weight GTP binding proteins to exocytic and endocytic compartments.
TL;DR: Findings provide evidence that members of the YPT1/SEC4 subfamily of GTP binding proteins are localized to specific exocytic and endocytic subcompartments in mammalian cells.
References
More filters
Journal ArticleDOI
DNA sequencing with chain-terminating inhibitors
TL;DR: A new method for determining nucleotide sequences in DNA is described, which makes use of the 2',3'-dideoxy and arabinon nucleoside analogues of the normal deoxynucleoside triphosphates, which act as specific chain-terminating inhibitors of DNA polymerase.
Journal ArticleDOI
Electrophoretic transfer of proteins from polyacrylamide gels to nitrocellulose sheets: procedure and some applications.
TL;DR: A method has been devised for the electrophoretic transfer of proteins from polyacrylamide gels to nitrocellulose sheets that results in quantitative transfer of ribosomal proteins from gels containing urea.
Journal ArticleDOI
Improved M13 phage cloning vectors and host strains: nucleotide sequences of the M13mp18 and pUC19 vectors
TL;DR: New Escherichia coli host strains have been constructed for the E. coli bacteriophage M13 and the high-copy-number pUC-plasmid cloning vectors and mutations introduced into these strains improve cloning of unmodified DNA and of repetitive sequences.
Journal ArticleDOI
G proteins: transducers of receptor-generated signals
TL;DR: This paper presents a meta-analysis of G Protein Interactions and its Foundations, which states that G Proteins are Law-Regulated and G Protein-Effector Interactions are Nonvolatile.
Journal ArticleDOI
Rapid and sensitive protein similarity searches
TL;DR: An algorithm was developed which facilitates the search for similarities between newly determined amino acid sequences and sequences already available in databases and increases sensitivity by giving high scores to those amino acid replacements which occur frequently in evolution.
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