Sandbox 208: Difference between revisions
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Rab-Guanosine biphosphate Dissociation Inhibitor (RabGDI) belongs to the transport cytoplasmic protein group. RabGDI was firstly isolated from bovine brain and three isoforms were isolated (α, β, γ). However, in the yeast [http://en.wikipedia.org/wiki/Saccharomyces_cerevisiae ''Saccharomyces cerevisiae''], only one isoform was identified: Gdi1p. | Rab-Guanosine biphosphate Dissociation Inhibitor (RabGDI) belongs to the transport cytoplasmic protein group. RabGDI was firstly isolated from bovine brain and three isoforms were isolated (α, β, γ). However, in the yeast [http://en.wikipedia.org/wiki/Saccharomyces_cerevisiae ''Saccharomyces cerevisiae''], only one isoform was identified: Gdi1p. | ||
In cells, vesicular traffic through the exocytic and endocytic pathways involves the activity of small Rab superfamilly [http://http://en.wikipedia.org/wiki/GTPase GTPases] which are named [http://http://en.wikipedia.org/wiki/Rab_(G-protein) Rab proteins]. Rab proteins exist in two different conformations: an active GTP bound conformation and an inactive GDP bound conformation. The process of switching between these two conformations requires a multitude of interacting and also regulatory proteins. Rab active form interacts with its effectors i.e GTPases activating proteins. On the contrary, the inactive conformation is recognized by guanine nucleotide exchange factors ([http://http://en.wikipedia.org/wiki/Guanine_nucleotide_exchange_factor GEF]) and regulators proteins including [http://http://en.wikipedia.org/wiki/Guanosine_nucleotide_dissociation_inhibitors GDI]. GDI is an inhibitory protein which extracts prenylated Rab proteins from membranes at the end of their cycle of activity and facilitates their delivery to the donor membranes. GDI is indispensable for the vesicular transport machinery functioning: its deletion is lethal. | In cells, vesicular traffic through the exocytic and endocytic pathways involves the activity of small Rab superfamilly [http://http://en.wikipedia.org/wiki/GTPase GTPases] which are named [http://http://en.wikipedia.org/wiki/Rab_(G-protein) Rab proteins]. Rab proteins exist in two different conformations: an active GTP bound conformation and an inactive GDP bound conformation. The process of switching between these two conformations requires a multitude of interacting and also regulatory proteins. Rab active form interacts with its effectors i.e GTPases activating proteins. On the contrary, the inactive conformation is recognized by guanine nucleotide exchange factors ([http://http://en.wikipedia.org/wiki/Guanine_nucleotide_exchange_factor GEF]) and regulators proteins including [http://http://en.wikipedia.org/wiki/Guanosine_nucleotide_dissociation_inhibitors GDI]. GDI is an inhibitory protein which extracts prenylated Rab proteins from membranes at the end of their cycle of activity and facilitates their delivery to the donor membranes. GDI is indispensable for the vesicular transport machinery functioning: its deletion is lethal. |