Many aspects of protein function regulation require specific protein-protein interactions to carry out the exact biochemical and cellular functions. The highly conserved members of the 14-3-3 protein family mediate such interactions and through binding to hundreds of other proteins provide multitude of regulatory functions, thus playing key roles in many cellular processes. The 14-3-3 protein binding can affect the function of the target protein in many ways including the modulation of its enzyme activity, its subcellular localization, its structure and stability, or its molecular interactions. In this minireview, we focus on mechanisms of the 14-3-3 protein-dependent regulation of three important 14-3-3 binding partners: yeast neutral trehalase Nth1, regulator of G-protein signaling 3 (RGS3), and phosducin.
- MeSH
- DNA-glykosylasy chemie ultrastruktura MeSH
- DNA-lyasa (apurinová nebo apyrimidinová) chemie ultrastruktura MeSH
- fosfoproteiny chemie ultrastruktura MeSH
- konformace proteinů MeSH
- lidé MeSH
- molekulární sekvence - údaje MeSH
- multienzymové komplexy chemie ultrastruktura MeSH
- oční proteiny chemie ultrastruktura MeSH
- proteiny 14-3-3 chemie ultrastruktura MeSH
- proteiny RGS chemie ultrastruktura MeSH
- proteiny vázající GTP - regulátory chemie ultrastruktura MeSH
- Schizosaccharomyces pombe - proteiny chemie ultrastruktura MeSH
- sekvence aminokyselin MeSH
- vazba proteinů MeSH
- vazebná místa MeSH
- vztahy mezi strukturou a aktivitou MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
Regulator of G protein signaling (RGS) proteins function as GTPase-activating proteins for the α-subunit of heterotrimeric G proteins. The function of certain RGS proteins is negatively regulated by 14-3-3 proteins, a family of highly conserved regulatory molecules expressed in all eukaryotes. In this study, we provide a structural mechanism for 14-3-3-dependent inhibition of RGS3-Gα interaction. We have used small angle x-ray scattering, hydrogen/deuterium exchange kinetics, and Förster resonance energy transfer measurements to determine the low-resolution solution structure of the 14-3-3ζ·RGS3 complex. The structure shows the RGS domain of RGS3 bound to the 14-3-3ζ dimer in an as-yet-unrecognized manner interacting with less conserved regions on the outer surface of the 14-3-3 dimer outside its central channel. Our results suggest that the 14-3-3 protein binding affects the structure of the Gα interaction portion of RGS3 as well as sterically blocks the interaction between the RGS domain and the Gα subunit of heterotrimeric G proteins.
- MeSH
- cirkulární dichroismus MeSH
- fosforylace MeSH
- hmotnostní spektrometrie MeSH
- lidé MeSH
- maloúhlový rozptyl MeSH
- proteiny 14-3-3 chemie genetika metabolismus MeSH
- proteiny aktivující GTPasu chemie genetika metabolismus MeSH
- proteiny vázající GTP chemie genetika metabolismus MeSH
- rezonanční přenos fluorescenční energie MeSH
- sekundární struktura proteinů MeSH
- signální transdukce MeSH
- terciární struktura proteinů MeSH
- vazba proteinů MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
FOXO4 is a member of the FOXO subgroup of forkhead transcription factors that constitute key components of a conserved signalling pathway that connects growth and stress signals to transcriptional control. Here, the 1.9 Å resolution crystal structure of the DNA-binding domain of human FOXO4 (FOXO4-DBD) bound to a 13 bp DNA duplex containing a FOXO consensus binding sequence is reported. The structure shows a similar recognition of the core sequence as has been shown for two other FOXO proteins. Helix H3 is docked into the major groove and provides all of the base-specific contacts, while the N-terminus and wing W1 make additional contacts with the phosphate groups of DNA. In contrast to other FOXO-DBD-DNA structures, the loop between helices H2 and H3 has a different conformation and participates in DNA binding. In addition, the structure of the FOXO4-DBD-DNA complex suggests that both direct water-DNA base contacts and the unique water-network interactions contribute to FOXO-DBD binding to the DNA in a sequence-specific manner.
- MeSH
- DNA chemie metabolismus MeSH
- konformace nukleové kyseliny MeSH
- krystalografie rentgenová MeSH
- lidé MeSH
- molekulární modely MeSH
- molekulární sekvence - údaje MeSH
- sekvence aminokyselin MeSH
- sekvenční seřazení MeSH
- strukturní homologie proteinů MeSH
- terciární struktura proteinů MeSH
- transkripční faktory chemie metabolismus MeSH
- vazba proteinů MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Yeast 14-3-3 protein isoforms BMH1 and BMH2 possess a distinctly variant C-terminal tail which differentiates them from the isoforms of higher eukaryotes. Their C-termini are longer and contain a polyglutamine stretch of unknown function. It is now well established that the C-terminal segment of 14-3-3 proteins plays an important regulatory role by functioning as an autoinhibitor which occupies the ligand binding groove and blocks the binding of inappropriate ligands. Whether the same holds true or not for the yeast isoforms is unclear. Therefore, we investigated the conformational behavior of the C-terminal segment of BMH proteins using various biophysical techniques. Dynamic light scattering, sedimentation velocity, time-resolved fluorescence anisotropy decay, and size exclusion chromatography measurements showed that the molecules of BMH proteins are significantly larger compared to the human 14-3-3zeta isoform. On the other hand, the sedimentation analysis confirmed that BMH proteins form dimers. Time-resolved tryptophan fluorescence experiments revealed no dramatic structural changes of the C-terminal segment upon the ligand binding. Taken together, the C-terminal segment of BMH proteins adopts a widely opened and extended conformation that makes difficult its folding into the ligand binding groove, thus increasing the apparent molecular size. It seems, therefore, that the C-terminal segment of BMH proteins does not function as an autoinhibitor.
- MeSH
- aminokyselinové motivy MeSH
- dimerizace MeSH
- konformace proteinů MeSH
- lidé MeSH
- molekulární sekvence - údaje MeSH
- proteiny 14-3-3 chemie genetika metabolismus MeSH
- Saccharomyces cerevisiae - proteiny chemie genetika metabolismus MeSH
- Saccharomyces cerevisiae chemie genetika metabolismus MeSH
- sekvence aminokyselin MeSH
- sekvenční seřazení MeSH
- terciární struktura proteinů MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Regulator of G protein signaling (RGS) proteins function as GTPase-activating proteins (GAPs) for the alpha-subunit of heterotrimeric G proteins. Several RGS proteins have been found to interact with 14-3-3 proteins. The 14-3-3 protein binding inhibits the GAP function of RGS proteins presumably by blocking their interaction with G(alpha) subunit. Since RGS proteins interact with G(alpha) subunits through their RGS domains, it is reasonable to assume that the 14-3-3 protein can either sterically occlude the G(alpha) interaction surface of RGS domain and/or change its structure. In this work, we investigated whether the 14-3-3 protein binding affects the structure of RGS3 using the time-resolved tryptophan fluorescence spectroscopy. Two single-tryptophan mutants of RGS3 were used to study conformational changes of RGS3 molecule. Our measurements revealed that the 14-3-3 protein binding induces structural changes in both the N-terminal part and the C-terminal RGS domain of phosphorylated RGS3 molecule. Experiments with the isolated RGS domain of RGS3 suggest that this domain alone can, to some extent, interact with the 14-3-3 protein in a phosphorylation-independent manner. In addition, a crystal structure of the RGS domain of RGS3 was solved at 2.3A resolution. The data obtained from the resolution of the structure of the RGS domain suggest that the 14-3-3 protein-induced conformational change affects the region within the G(alpha)-interacting portion of the RGS domain. This can explain the inhibitory effect of the 14-3-3 protein on GAP activity of RGS3.
- MeSH
- fluorescenční spektrometrie MeSH
- fosforylace MeSH
- interakční proteinové domény a motivy MeSH
- krystalografie rentgenová MeSH
- lidé MeSH
- molekulární modely MeSH
- multiproteinové komplexy MeSH
- mutageneze cílená MeSH
- podjednotky proteinů MeSH
- proteiny 14-3-3 chemie metabolismus MeSH
- proteiny aktivující GTPasu chemie genetika metabolismus MeSH
- proteiny vázající GTP chemie genetika metabolismus MeSH
- rekombinantní proteiny chemie genetika metabolismus MeSH
- rezonanční přenos fluorescenční energie MeSH
- sekvence aminokyselin MeSH
- spektrometrie hmotnostní - ionizace laserem za účasti matrice MeSH
- stabilita proteinů MeSH
- substituce aminokyselin MeSH
- terciární struktura proteinů MeSH
- tryptofan chemie MeSH
- vazebná místa MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- techniky in vitro MeSH
