GONUTS has been updated to MW1.31 Most things seem to be working but be sure to report problems.

Have any questions? Please email us at ecoliwiki@gmail.com

PMID:10791963

From GONUTS
Jump to: navigation, search
Citation

Chatterjee, TK and Fisher, RA (2000) Cytoplasmic, nuclear, and golgi localization of RGS proteins. Evidence for N-terminal and RGS domain sequences as intracellular targeting motifs. J. Biol. Chem. 275:24013-21

Abstract

RGS proteins comprise a family of proteins named for their ability to negatively regulate heterotrimeric G protein signaling. Biochemical studies suggest that members of this protein family act as GTPase-activating proteins for certain Galpha subunits, thereby accelerating the turn-off mechanism of Galpha and terminating signaling by both Galpha and Gbetagamma subunits. In the present study, we used confocal microscopy to examine the intracellular distribution of several RGS proteins in COS-7 cells expressing RGS-green fluorescent protein (GFP) fusion proteins and in cells expressing RGS proteins endogenously. RGS2 and RGS10 accumulated in the nucleus of COS-7 cells transfected with GFP constructs of these proteins. In contrast, RGS4 and RGS16 accumulated in the cytoplasm of COS-7 transfectants. As observed in COS-7 cells, RGS4 exhibited cytoplasmic localization in mouse neuroblastoma cells, and RGS10 exhibited nuclear localization in human glioma cells. Deletion or alanine substitution of an N-terminal leucine repeat motif present in both RGS4 and RGS16, a domain identified as a nuclear export sequence in HIV Rev and other proteins, promoted nuclear localization of these proteins in COS-7 cells. In agreement with this observation, treatment of mouse neuroblastoma cells with leptomycin B to inhibit nuclear protein export by exportin1 resulted in accumulation of RGS4 in the nucleus of these cells. GFP fusions of RGS domains of RGS proteins localized in the nucleus, suggesting that nuclear localization of RGS proteins results from nuclear targeting via RGS domain sequences. RGSZ, which shares with RGS-GAIP a cysteine-rich string in its N-terminal region, localized to the Golgi complex in COS-7 cells. Deletion of the N-terminal domain of RGSZ that includes the cysteine motif promoted nuclear localization of RGSZ. None of the RGS proteins examined were localized at the plasma membrane. These results demonstrate that RGS proteins localize in the nucleus, the cytoplasm, or shuttle between the nucleus and cytoplasm as nucleo-cytoplasmic shuttle proteins. RGS proteins localize differentially within cells as a result of structural differences among these proteins that do not appear to be important determinants for their G protein-regulating activities. These findings suggest involvement of RGS proteins in more complex cellular functions than currently envisioned.

Links

PubMed Online version:10.1074/jbc.M002082200

Keywords

Amino Acid Sequence; Animals; Biological Transport; Cell Compartmentation; Cell Nucleus/chemistry; Cell Nucleus/metabolism; Cytoplasm/chemistry; Cytoplasm/metabolism; Golgi Apparatus/chemistry; Golgi Apparatus/metabolism; Green Fluorescent Proteins; Humans; Luminescent Proteins/genetics; Luminescent Proteins/isolation & purification; Luminescent Proteins/metabolism; Mice; Microscopy, Fluorescence; Molecular Sequence Data; Nuclear Localization Signals; Protein Sorting Signals; Proteins; RGS Proteins/genetics; RGS Proteins/isolation & purification; RGS Proteins/metabolism; Recombinant Proteins/isolation & purification; Recombinant Proteins/metabolism; Repetitive Sequences, Amino Acid; Sequence Homology, Amino Acid

Significance

Annotations

Gene product Qualifier GO Term Evidence Code with/from Aspect Extension Notes Status

HUMAN:RGS2

part_of

GO:0005634: nucleus

ECO:0000314: direct assay evidence used in manual assertion

C

Seeded From UniProt

complete

HUMAN:RGS2

GO:0005634: nucleus

ECO:0000314:

C

Fig.2

complete
CACAO 6946

HUMAN:RGS4

GO:0005737: cytoplasm

ECO:0000314:

C

Fig.2

complete
CACAO 6948

HUMAN:RGS4

GO:0005634: nucleus

ECO:0000314:

C

Fig.4

complete
CACAO 6950

HUMAN:RGS4

part_of

GO:0005634: nucleus

ECO:0000314: direct assay evidence used in manual assertion

C

Seeded From UniProt

complete

HUMAN:RGS4

part_of

GO:0005737: cytoplasm

ECO:0000314: direct assay evidence used in manual assertion

C

Seeded From UniProt

complete

HUMAN:RGS10

GO:0005096: GTPase activator activity

ECO:0000314:

F

Figure 3 shows RGS16 activates GFP by turning off Galpha and Gbeta quicker,as seen in the overlay (yellow) in flourescence picture shows the activation of GFP.

complete
CACAO 6503

HUMAN:RGS10

GO:0005634: nucleus

ECO:0000314:

C

Fig.2

complete
CACAO 6947

HUMAN:RGS10

part_of

GO:0005634: nucleus

ECO:0000314: direct assay evidence used in manual assertion

C

Seeded From UniProt

complete

HUMAN:RGS16

GO:0005737: cytoplasm

ECO:0000314:

C

Fig.2

complete
CACAO 6949

HUMAN:RGS16

part_of

GO:0005737: cytoplasm

ECO:0000314: direct assay evidence used in manual assertion

C

Seeded From UniProt

complete

HUMAN:RGS20

GO:0005737: cytoplasm

ECO:0000315:

C

Fig.12

complete
CACAO 6953

HUMAN:RGS20

GO:0005802: trans-Golgi network

ECO:0000315:

C

Fig.12

complete
CACAO 6954

HUMAN:RGS20

part_of

GO:0005802: trans-Golgi network

ECO:0000315: mutant phenotype evidence used in manual assertion

C

Seeded From UniProt

complete

HUMAN:RGS20

part_of

GO:0005737: cytoplasm

ECO:0000315: mutant phenotype evidence used in manual assertion

C

Seeded From UniProt

complete


See also

References

See Help:References for how to manage references in GONUTS.