scholarly journals Identification of Heterotrimeric G Protein γ3 Subunit in Rice Plasma Membrane

2018 ◽  
Vol 19 (11) ◽  
pp. 3591 ◽  
Author(s):  
Aki Nishiyama ◽  
Sakura Matsuta ◽  
Genki Chaya ◽  
Takafumi Itoh ◽  
Kotaro Miura ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Higher Plants ◽  
Rice Genome ◽  
Amino Acid Residues ◽  
Subunit Gene ◽  
Α Subunit ◽  
Γ Subunit ◽  
Domain Antibody ◽  
C Terminus ◽  
Liquid Chromatography Tandem Mass

Heterotrimeric G proteins are important molecules for regulating plant architecture and transmitting external signals to intracellular target proteins in higher plants and mammals. The rice genome contains one canonical α subunit gene (RGA1), four extra-large GTP-binding protein genes (XLGs), one canonical β subunit gene (RGB1), and five γ subunit genes (tentatively named RGG1, RGG2, RGG3/GS3/Mi/OsGGC1, RGG4/DEP1/DN1/OsGGC3, and RGG5/OsGGC2). RGG1 encodes the canonical γ subunit; RGG2 encodes the plant-specific type of γ subunit with additional amino acid residues at the N-terminus; and the remaining three γ subunit genes encode the atypical γ subunits with cysteine abundance at the C-terminus. We aimed to identify the RGG3/GS3/Mi/OsGGC1 gene product, Gγ3, in rice tissues using the anti-Gγ3 domain antibody. We also analyzed the truncated protein, Gγ3∆Cys, in the RGG3/GS3/Mi/OsGGC1 mutant, Mi, using the anti-Gγ3 domain antibody. Based on nano-liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis, the immunoprecipitated Gγ3 candidates were confirmed to be Gγ3. Similar to α (Gα) and β subunits (Gβ), Gγ3 was enriched in the plasma membrane fraction, and accumulated in the flower tissues. As RGG3/GS3/Mi/OsGGC1 mutants show the characteristic phenotype in flowers and consequently in seeds, the tissues that accumulated Gγ3 corresponded to the abnormal tissues observed in RGG3/GS3/Mi/OsGGC1 mutants.

scholarly journals Characterization of Heterotrimeric G Protein γ4 Subunit in Rice

2018 ◽  
Vol 19 (11) ◽  
pp. 3596 ◽  
Author(s):  
Sakura Matsuta ◽  
Aki Nishiyama ◽  
Genki Chaya ◽  
Takafumi Itoh ◽  
Kotaro Miura ◽  
...  
Keyword(s):  
G Protein ◽  
G Proteins ◽  
Higher Plants ◽  
Yeast Cells ◽  
Mass Spectrometry Analysis ◽  
Heterotrimeric G Proteins ◽  
Subunit Gene ◽  
Heterotrimeric G Protein ◽  
Α Subunit ◽  
Γ Subunit

Heterotrimeric G proteins are the molecule switch that transmits information from external signals to intracellular target proteins in mammals and yeast cells. In higher plants, heterotrimeric G proteins regulate plant architecture. Rice harbors one canonical α subunit gene (RGA1), four extra-large GTP-binding protein genes (XLGs), one canonical β-subunit gene (RGB1), and five γ-subunit genes (tentatively designated RGG1, RGG2, RGG3/GS3/Mi/OsGGC1, RGG4/DEP1/DN1/qPE9-1/OsGGC3, and RGG5/OsGGC2) as components of the heterotrimeric G protein complex. Among the five γ-subunit genes, RGG1 encodes the canonical γ-subunit, RGG2 encodes a plant-specific type of γ-subunit with additional amino acid residues at the N-terminus, and the remaining three γ-subunit genes encode atypical γ-subunits with cysteine-rich C-termini. We characterized the RGG4/DEP1/DN1/qPE9-1/OsGGC3 gene product Gγ4 in the wild type (WT) and truncated protein Gγ4∆Cys in the RGG4/DEP1/DN1/qPE9-1/OsGGC3 mutant, Dn1-1, as littele information regarding the native Gγ4 and Gγ4∆Cys proteins is currently available. Based on liquid chromatography-tandem mass spectrometry analysis, immunoprecipitated Gγ4 candidates were confirmed as actual Gγ4. Similar to α-(Gα) and β-subunits (Gβ), Gγ4 was enriched in the plasma membrane fraction and accumulated in the developing leaf sheath. As RGG4/DEP1/DN1/qPE9-1/OsGGC3 mutants exhibited dwarfism, tissues that accumulated Gγ4 corresponded to the abnormal tissues observed in RGG4/DEP1/DN1/qPE9-1/OsGGC3 mutants.

scholarly journals The N Terminus of GTPγS-activated Transducin α-Subunit Interacts with the C Terminus of the cGMP Phosphodiesterase γ-Subunit

2006 ◽  
Vol 281 (10) ◽  
pp. 6194-6202 ◽  
Author(s):  
Jennifer E. Grant ◽  
Lian-Wang Guo ◽  
Martha M. Vestling ◽  
Kirill A. Martemyanov ◽  
Vadim Y. Arshavsky ◽  
...  
Keyword(s):  
Α Subunit ◽  
Cgmp Phosphodiesterase ◽  
Γ Subunit ◽  
C Terminus ◽  
N Terminus

scholarly journals Phosphatidylinositol 3,4,5-trisphosphate Localization in Recycling Endosomes Is Necessary for AP-1B–dependent Sorting in Polarized Epithelial Cells

2010 ◽  
Vol 21 (1) ◽  
pp. 95-105 ◽  
Author(s):  
Ian C. Fields ◽  
Shelby M. King ◽  
Elina Shteyn ◽  
Richard S. Kang ◽  
Heike Fölsch
Keyword(s):  
Plasma Membrane ◽  
Epithelial Cell ◽  
Epithelial Cells ◽  
Basolateral Membrane ◽  
Apical Plasma Membrane ◽  
Amino Acid Residues ◽  
Recycling Endosomes ◽  
C Terminus ◽  
Polarized Epithelial Cells ◽  
Clathrin Adaptor

Polarized epithelial cells coexpress two almost identical AP-1 clathrin adaptor complexes: the ubiquitously expressed AP-1A and the epithelial cell–specific AP-1B. The only difference between the two complexes is the incorporation of the respective medium subunits μ1A or μ1B, which are responsible for the different functions of AP-1A and AP-1B in TGN to endosome or endosome to basolateral membrane targeting, respectively. Here we demonstrate that the C-terminus of μ1B is important for AP-1B recruitment onto recycling endosomes. We define a patch of three amino acid residues in μ1B that are necessary for recruitment of AP-1B onto recycling endosomes containing phosphatidylinositol 3,4,5-trisphosphate [PI(3,4,5)P3]. We found this lipid enriched in recycling endosomes of epithelial cells only when AP-1B is expressed. Interfering with PI(3,4,5)P3 formation leads to displacement of AP-1B from recycling endosomes and missorting of AP-1B–dependent cargo to the apical plasma membrane. In conclusion, PI(3,4,5)P3 formation in recycling endosomes is essential for AP-1B function.

scholarly journals Structural basis for distinctive recognition of fibrinogen γC peptide by the platelet integrin αIIbβ3

2008 ◽  
Vol 182 (4) ◽  
pp. 791-800 ◽  
Author(s):  
Timothy A. Springer ◽  
Jianghai Zhu ◽  
Tsan Xiao
Keyword(s):  
Metal Ion ◽  
Structural Data ◽  
Structural Basis ◽  
Side Chain ◽  
Α Subunit ◽  
Integrin Αiibβ3 ◽  
Rgd Motif ◽  
Γ Subunit ◽  
Fibrinogen Binding ◽  
C Terminus

Hemostasis and thrombosis (blood clotting) involve fibrinogen binding to integrin αIIbβ3 on platelets, resulting in platelet aggregation. αvβ3 binds fibrinogen via an Arg-Asp-Gly (RGD) motif in fibrinogen's α subunit. αIIbβ3 also binds to fibrinogen; however, it does so via an unstructured RGD-lacking C-terminal region of the γ subunit (γC peptide). These distinct modes of fibrinogen binding enable αIIbβ3 and αvβ3 to function cooperatively in hemostasis. In this study, crystal structures reveal the integrin αIIbβ3–γC peptide interface, and, for comparison, integrin αIIbβ3 bound to a lamprey γC primordial RGD motif. Compared with RGD, the GAKQAGDV motif in γC adopts a different backbone configuration and binds over a more extended region. The integrin metal ion–dependent adhesion site (MIDAS) Mg2+ ion binds the γC Asp side chain. The adjacent to MIDAS (ADMIDAS) Ca2+ ion binds the γC C terminus, revealing a contribution for ADMIDAS in ligand binding. Structural data from this natively disordered γC peptide enhances our understanding of the involvement of γC peptide and integrin αIIbβ3 in hemostasis and thrombosis.

scholarly journals C-Terminal Truncations of the Saccharomyces cerevisiae PMA1 H+-ATPase Have Major Impacts on Protein Conformation, Trafficking, Quality Control, and Function

2013 ◽  
Vol 13 (1) ◽  
pp. 43-52 ◽  
Author(s):  
A. Brett Mason ◽  
Kenneth E. Allen ◽  
Carolyn W. Slayman
Keyword(s):  
Amino Acids ◽  
Quality Control ◽  
Plasma Membrane ◽  
Atpase Activity ◽  
Amino Acid Residues ◽  
Membrane Expression ◽  
C Terminus ◽  
Conditional Expression ◽  
Membrane Spanning ◽  
And Function

ABSTRACTThe C-terminal tail of yeast plasma membrane (PM) H+-ATPase extends approximately 38 amino acids beyond the final membrane-spanning segment (TM10) of the protein and is known to be required for successful trafficking, stability, and regulation of enzyme activity. To carry out a detailed functional survey of the entire length of the tail, we generated 15 stepwise truncation mutants. Eleven of them, lacking up to 30 amino acids from the extreme terminus, were able to support cell growth, even though there were detectable changes in plasma membrane expression, protein stability, and ATPase activity. Three functionally distinct regions of the C terminus could be defined. (i) Truncations upstream of Lys889, removing more than 30 amino acid residues, yielded no viable mutants, and conditional expression of such constructs supported the conclusion that the stretch from Ala881(at the end of TM10) to Gly888is required for stable folding and PM targeting. (ii) The stretch between Lys889and Lys916, a region known to be subject to kinase-mediated posttranslational modification, was shown here to be ubiquitinated in carbon-starved cells as part of cellular quality control and to be essential for normal ATPase folding and stability, as well as for autoinhibition of ATPase activity during glucose starvation. (iii) Finally, removal of even one or two residues (Glu917and Thr918) from the extreme C terminus led to visibly reduced expression of the ATPase at the plasma membrane. Thus, the C terminus is much more than a simple appendage and profoundly influences the structure, biogenesis, and function of the yeast H+-ATPase.

scholarly journals Interaction Between the SNARE SYP121 and the Plasma Membrane Aquaporin PIP2;7 Involves Different Protein Domains

2021 ◽  
Vol 11 ◽  
Author(s):  
Timothée Laloux ◽  
Irwin Matyjaszczyk ◽  
Simon Beaudelot ◽  
Charles Hachez ◽  
François Chaumont
Keyword(s):  
Plasma Membrane ◽  
Transmembrane Domain ◽  
Interaction Mechanism ◽  
Bimolecular Fluorescence Complementation ◽  
Physical Interaction ◽  
Amino Acid Residues ◽  
Interaction Domain ◽  
C Terminus ◽  
Full Interaction ◽  
Plasma Membrane Intrinsic Proteins

Plasma membrane intrinsic proteins (PIPs) are channels facilitating the passive diffusion of water and small solutes. Arabidopsis PIP2;7 trafficking occurs through physical interaction with SNARE proteins including the syntaxin SYP121, a plasma membrane Qa-SNARE involved in membrane fusion. To better understand the interaction mechanism, we aimed at identifying the interaction motifs in SYP121 and PIP2;7 using ratiometric bimolecular fluorescence complementation assays in Nicotiana benthamiana. SYP121 consists of four regions, N, H, Q, and C, and sequential deletions revealed that the C region, containing the transmembrane domain, as well as the H and Q regions, containing the Habc and Qa-SNARE functional domains, interact with PIP2;7. Neither the linker between the Habc and the Qa-SNARE domains nor the H or Q regions alone could fully restore the interaction with PIP2;7, suggesting that the interacting motif depends on the conformation taken by the HQ region. When investigating the interacting motif(s) in PIP2;7, we observed that deletion of the cytosolic N- and/or C- terminus led to a significant decrease in the interaction with SYP121. Shorter deletions revealed that at the N-terminal amino acid residues 18–26 were involved in the interaction. Domain swapping experiments between PIP2;7 and PIP2;6, a PIP isoform that does not interact with SYP121, showed that PIP2;7 N-terminal part up to the loop C was required to restore the full interaction signal, suggesting that, as it is the case for SYP121, the interaction motif(s) in PIP2;7 depend on the protein conformation. Finally, we also showed that PIP2;7 physically interacted with other Arabidopsis SYP1s and SYP121 orthologs.

A basolateral sorting signal is encoded in the α-subunit of Na-K-ATPase

1998 ◽  
Vol 274 (3) ◽  
pp. C688-C696 ◽  
Author(s):  
T. R. Muth ◽  
C. J. Gottardi ◽  
D. L. Roush ◽  
M. J. Caplan
Keyword(s):  
Amino Acids ◽  
Plasma Membrane ◽  
Surface Expression ◽  
Apical Surface ◽  
Amino Acid Residues ◽  
Β Subunit ◽  
Α Subunit ◽  
Sorting Signal ◽  
Apical Sorting ◽  
Gastric Parietal Cells

Na-K-ATPase and H-K-ATPase are highly homologous ion pumps that exhibit distinct plasma membrane distributions in epithelial cells. We have studied the α-subunits of these heterodimeric pumps to identify the protein domains responsible for their polarized sorting. A chimeric α-subunit construct (N519H) was generated in which the first 519 amino acid residues correspond to the Na-K-ATPase sequence and the remaining 500 amino acids are derived from the H-K-ATPase sequence. In stably transfected LLC-PK1cell lines, we found that the N519H chimera is restricted to the basolateral surface under steady-state conditions, suggesting that residues within the NH2-terminal 519 amino acids of the Na-K-ATPase α-subunit contain a basolateral sorting signal. H-K-ATPase β-subunit expressed alone in LLC-PK1cells accumulates at the apical surface. When coexpressed with N519H, the H-K-ATPase β-subunit assembles with this chimera and accompanies it to the basolateral surface. Thus the NH2-terminal basolateral signal in the Na-K-ATPase α-subunit masks or is dominant over any apical sorting information present in the β-polypeptide. In gastric parietal cells, the H-K-ATPase β-subunit targets the H-K-ATPase to an intracellular vesicular compartment which fuses with the plasma membrane in response to secretagogue stimulation. To test whether the chimera-H-K-ATPase β-subunit complex is directed to a similar compartment in LLC-PK1cells, we treated transfected cells with drugs that raise intracellular adenosine 3′,5′-cyclic monophosphate (cAMP) levels. Elevation of cytosolic cAMP increased the surface expression of both the N519H chimera and the H-K-ATPase β-subunit. This increase in surface expression, however, appears to be the result of transcriptional upregulation and not recruitment of chimera to the surface from a cAMP-inducible compartment.

Localization of Adenosine Triphosphatase Activity in the Phleom of Nicotiana Tabacum

1972 ◽  
Vol 30 ◽  
pp. 230-231
Author(s):  
James Cronshaw ◽  
Jamison E. Gilder
Keyword(s):  
Plasma Membrane ◽  
Atpase Activity ◽  
Adenosine Triphosphatase ◽  
Higher Plants ◽  
High Surface ◽  
Root Tip ◽  
Animal Cells ◽  
Physiological Processes ◽  
Tip Cells ◽  
Atpase Localization

Adenosine triphosphatase (ATPase) activity has been shown to be associated with numerous physiological processes in both plants and animal cells. Biochemical studies have shown that in higher plants ATPase activity is high in cell wall preparations and is associated with the plasma membrane, nuclei, mitochondria, chloroplasts and lysosomes. However, there have been only a few ATPase localization studies of higher plants at the electron microscope level. Poux (1967) demonstrated ATPase activity associated with most cellular organelles in the protoderm cells of Cucumis roots. Hall (1971) has demonstrated ATPase activity in root tip cells of Zea mays. There was high surface activity largely associated with the plasma membrane and plasmodesmata. ATPase activity was also demonstrated in mitochondria, dictyosomes, endoplasmic reticulum and plastids.

Sign in / Sign up

Export Citation Format

Share Document