A newly identified Rab-GDI paralogue has a role in neural development in amphibia.
Vesicle shuttling is critical for many cellular and organismal processes, including embryonic development. GDI proteins contribute to vesicle shuttling by regulating the activity of Rab GTPases, controlling their cycling between the inactive cytosol and active membrane bound states. While identifying genes controlled by A-form DNA sequences we discovered a previously unknown member of the GDI family, GDI3. The GDI3 gene is found only in amphibians and fish and is developmentally expressed in Xenopus from neurula stages onwards in the neural plate, and subsequently in both dorsal and anterior structures. Depletion or over-expression of the GDI3 protein in Xenopus embryos gives rise to very similar phenotypes, suggesting that strict control of GDI3 protein levels is required for correct embryonic development. Our analysis suggests the evolutionary origins of GDI3 and that it is functionally distinct from GDI1. Predicted structural analysis of GDI3 suggests that the key difference between GDI1 and GDI3 lies in their lipid binding pockets.
Biophysics Laboratories, School of Biological Sciences, Institute of Biomedical and Biomolecular Science, University of Portsmouth, St Michaels Building, White Swan Road, Portsmouth PO1 2DT, UK.
Liliya
L
Nazlamova
Biophysics Laboratories, School of Biological Sciences, Institute of Biomedical and Biomolecular Science, University of Portsmouth, St Michaels Building, White Swan Road, Portsmouth PO1 2DT, UK.
Anna
A
Noble
Biophysics Laboratories, School of Biological Sciences, Institute of Biomedical and Biomolecular Science, University of Portsmouth, St Michaels Building, White Swan Road, Portsmouth PO1 2DT, UK.
Frank R
FR
Schubert
Biophysics Laboratories, School of Biological Sciences, Institute of Biomedical and Biomolecular Science, University of Portsmouth, St Michaels Building, White Swan Road, Portsmouth PO1 2DT, UK.
John
J
McGeehan
Biophysics Laboratories, School of Biological Sciences, Institute of Biomedical and Biomolecular Science, University of Portsmouth, St Michaels Building, White Swan Road, Portsmouth PO1 2DT, UK.
Fiona
F
Myers
Biophysics Laboratories, School of Biological Sciences, Institute of Biomedical and Biomolecular Science, University of Portsmouth, St Michaels Building, White Swan Road, Portsmouth PO1 2DT, UK.
Matt
M
Guille
Biophysics Laboratories, School of Biological Sciences, Institute of Biomedical and Biomolecular Science, University of Portsmouth, St Michaels Building, White Swan Road, Portsmouth PO1 2DT, UK. Electronic address: garry.scarlett@port.ac.uk.
Garry
G
Scarlett
D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D018507:Gene Expression Regulation, Developmental; D020730:Guanine Nucleotide Dissociation Inhibitors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008958:Models, Molecular; D055495:Neurogenesis / Q000235:genetics / Q000502:physiology*; D010802:Phylogeny; D014981:Xenopus / Q000196:embryology* / Q000235:genetics / Q000378:metabolism*; D029867:Xenopus Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D020691:rab GTP-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
D020730:Guanine Nucleotide Dissociation Inhibitors; D029867:Xenopus Proteins; D004247:DNA; D020691:rab GTP-Binding Proteins
GDI1; GDI2; GDI3; Rab; Vesicle trafficking; Xenopus