Splice variants of SmgGDS control small gtpase prenylation and membrane localization

Tracy J. Berg, Adam J. Gastonguay, Ellen L. Lorimer, John R. Kuhnmuench, Rongshan Li, Alan P Fields, Carol L. Williams

Research output: Contribution to journalArticle

40 Citations (Scopus)

Abstract

Ras and Rho small GTPases possessing a C-terminal polybasic region (PBR) are vital signaling proteins whose misregulation can lead to cancer. Signaling by these proteins depends on their ability to bind guanine nucleotides and their prenylation with a geranylgeranyl or farnesyl isoprenoid moiety and subsequent trafficking to cellular membranes. There is little previous evidence that cellular signals can restrain nonprenylated GTPases from entering the prenylation pathway, leading to the general belief that PBR-possessing GTPases are prenylated as soon as they are synthesized. Here, we present evidence that challenges this belief. We demonstrate that insertion of the dominant negative mutation to inhibit GDP/GTP exchange diminishes prenylation of Rap1A and RhoA, enhances prenylation of Rac1, and does not detectably alter prenylation of K-Ras. Our results indicate that the entrance and passage of these small GTPases through the prenylation pathway is regulated by two splice variants of SmgGDS, a protein that has been reported to promote GDP/GTP exchange by PBR-possessing GTPases and to be up-regulated in several forms of cancer. We show that the previously characterized 558-residue SmgGDS splice variant (SmgGDS-558) selectively associates with prenylated small GTPases and facilitates trafficking of Rap1A to the plasma membrane, whereas the less well characterized 607-residue SmgGDS splice variant (SmgGDS-607) associates with nonprenylated GTPases and regulates the entry of Rap1A, RhoA, and Rac1 into the prenylation pathway. These results indicate that guanine nucleotide exchange and interactions with SmgGDS splice variants can regulate the entrance and passage of PBR-possessing small GTPases through the prenylation pathway.

Original languageEnglish (US)
Pages (from-to)35255-35266
Number of pages12
JournalJournal of Biological Chemistry
Volume285
Issue number46
DOIs
StatePublished - Nov 12 2010

Fingerprint

Prenylation
Monomeric GTP-Binding Proteins
GTP Phosphohydrolases
Membranes
Guanine Nucleotides
Guanosine Triphosphate
Proteins
Terpenes
Cell membranes
rho GTP-Binding Proteins
Neoplasms
Cell Membrane
Mutation

ASJC Scopus subject areas

  • Biochemistry
  • Cell Biology
  • Molecular Biology

Cite this

Berg, T. J., Gastonguay, A. J., Lorimer, E. L., Kuhnmuench, J. R., Li, R., Fields, A. P., & Williams, C. L. (2010). Splice variants of SmgGDS control small gtpase prenylation and membrane localization. Journal of Biological Chemistry, 285(46), 35255-35266. https://doi.org/10.1074/jbc.M110.129916

Splice variants of SmgGDS control small gtpase prenylation and membrane localization. / Berg, Tracy J.; Gastonguay, Adam J.; Lorimer, Ellen L.; Kuhnmuench, John R.; Li, Rongshan; Fields, Alan P; Williams, Carol L.

In: Journal of Biological Chemistry, Vol. 285, No. 46, 12.11.2010, p. 35255-35266.

Research output: Contribution to journalArticle

Berg, TJ, Gastonguay, AJ, Lorimer, EL, Kuhnmuench, JR, Li, R, Fields, AP & Williams, CL 2010, 'Splice variants of SmgGDS control small gtpase prenylation and membrane localization', Journal of Biological Chemistry, vol. 285, no. 46, pp. 35255-35266. https://doi.org/10.1074/jbc.M110.129916
Berg, Tracy J. ; Gastonguay, Adam J. ; Lorimer, Ellen L. ; Kuhnmuench, John R. ; Li, Rongshan ; Fields, Alan P ; Williams, Carol L. / Splice variants of SmgGDS control small gtpase prenylation and membrane localization. In: Journal of Biological Chemistry. 2010 ; Vol. 285, No. 46. pp. 35255-35266.
@article{185c295edf0c439384e7d6116e6063c9,
title = "Splice variants of SmgGDS control small gtpase prenylation and membrane localization",
abstract = "Ras and Rho small GTPases possessing a C-terminal polybasic region (PBR) are vital signaling proteins whose misregulation can lead to cancer. Signaling by these proteins depends on their ability to bind guanine nucleotides and their prenylation with a geranylgeranyl or farnesyl isoprenoid moiety and subsequent trafficking to cellular membranes. There is little previous evidence that cellular signals can restrain nonprenylated GTPases from entering the prenylation pathway, leading to the general belief that PBR-possessing GTPases are prenylated as soon as they are synthesized. Here, we present evidence that challenges this belief. We demonstrate that insertion of the dominant negative mutation to inhibit GDP/GTP exchange diminishes prenylation of Rap1A and RhoA, enhances prenylation of Rac1, and does not detectably alter prenylation of K-Ras. Our results indicate that the entrance and passage of these small GTPases through the prenylation pathway is regulated by two splice variants of SmgGDS, a protein that has been reported to promote GDP/GTP exchange by PBR-possessing GTPases and to be up-regulated in several forms of cancer. We show that the previously characterized 558-residue SmgGDS splice variant (SmgGDS-558) selectively associates with prenylated small GTPases and facilitates trafficking of Rap1A to the plasma membrane, whereas the less well characterized 607-residue SmgGDS splice variant (SmgGDS-607) associates with nonprenylated GTPases and regulates the entry of Rap1A, RhoA, and Rac1 into the prenylation pathway. These results indicate that guanine nucleotide exchange and interactions with SmgGDS splice variants can regulate the entrance and passage of PBR-possessing small GTPases through the prenylation pathway.",
author = "Berg, {Tracy J.} and Gastonguay, {Adam J.} and Lorimer, {Ellen L.} and Kuhnmuench, {John R.} and Rongshan Li and Fields, {Alan P} and Williams, {Carol L.}",
year = "2010",
month = "11",
day = "12",
doi = "10.1074/jbc.M110.129916",
language = "English (US)",
volume = "285",
pages = "35255--35266",
journal = "Journal of Biological Chemistry",
issn = "0021-9258",
publisher = "American Society for Biochemistry and Molecular Biology Inc.",
number = "46",

}

TY - JOUR

T1 - Splice variants of SmgGDS control small gtpase prenylation and membrane localization

AU - Berg, Tracy J.

AU - Gastonguay, Adam J.

AU - Lorimer, Ellen L.

AU - Kuhnmuench, John R.

AU - Li, Rongshan

AU - Fields, Alan P

AU - Williams, Carol L.

PY - 2010/11/12

Y1 - 2010/11/12

N2 - Ras and Rho small GTPases possessing a C-terminal polybasic region (PBR) are vital signaling proteins whose misregulation can lead to cancer. Signaling by these proteins depends on their ability to bind guanine nucleotides and their prenylation with a geranylgeranyl or farnesyl isoprenoid moiety and subsequent trafficking to cellular membranes. There is little previous evidence that cellular signals can restrain nonprenylated GTPases from entering the prenylation pathway, leading to the general belief that PBR-possessing GTPases are prenylated as soon as they are synthesized. Here, we present evidence that challenges this belief. We demonstrate that insertion of the dominant negative mutation to inhibit GDP/GTP exchange diminishes prenylation of Rap1A and RhoA, enhances prenylation of Rac1, and does not detectably alter prenylation of K-Ras. Our results indicate that the entrance and passage of these small GTPases through the prenylation pathway is regulated by two splice variants of SmgGDS, a protein that has been reported to promote GDP/GTP exchange by PBR-possessing GTPases and to be up-regulated in several forms of cancer. We show that the previously characterized 558-residue SmgGDS splice variant (SmgGDS-558) selectively associates with prenylated small GTPases and facilitates trafficking of Rap1A to the plasma membrane, whereas the less well characterized 607-residue SmgGDS splice variant (SmgGDS-607) associates with nonprenylated GTPases and regulates the entry of Rap1A, RhoA, and Rac1 into the prenylation pathway. These results indicate that guanine nucleotide exchange and interactions with SmgGDS splice variants can regulate the entrance and passage of PBR-possessing small GTPases through the prenylation pathway.

AB - Ras and Rho small GTPases possessing a C-terminal polybasic region (PBR) are vital signaling proteins whose misregulation can lead to cancer. Signaling by these proteins depends on their ability to bind guanine nucleotides and their prenylation with a geranylgeranyl or farnesyl isoprenoid moiety and subsequent trafficking to cellular membranes. There is little previous evidence that cellular signals can restrain nonprenylated GTPases from entering the prenylation pathway, leading to the general belief that PBR-possessing GTPases are prenylated as soon as they are synthesized. Here, we present evidence that challenges this belief. We demonstrate that insertion of the dominant negative mutation to inhibit GDP/GTP exchange diminishes prenylation of Rap1A and RhoA, enhances prenylation of Rac1, and does not detectably alter prenylation of K-Ras. Our results indicate that the entrance and passage of these small GTPases through the prenylation pathway is regulated by two splice variants of SmgGDS, a protein that has been reported to promote GDP/GTP exchange by PBR-possessing GTPases and to be up-regulated in several forms of cancer. We show that the previously characterized 558-residue SmgGDS splice variant (SmgGDS-558) selectively associates with prenylated small GTPases and facilitates trafficking of Rap1A to the plasma membrane, whereas the less well characterized 607-residue SmgGDS splice variant (SmgGDS-607) associates with nonprenylated GTPases and regulates the entry of Rap1A, RhoA, and Rac1 into the prenylation pathway. These results indicate that guanine nucleotide exchange and interactions with SmgGDS splice variants can regulate the entrance and passage of PBR-possessing small GTPases through the prenylation pathway.

UR - http://www.scopus.com/inward/record.url?scp=78149231569&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=78149231569&partnerID=8YFLogxK

U2 - 10.1074/jbc.M110.129916

DO - 10.1074/jbc.M110.129916

M3 - Article

VL - 285

SP - 35255

EP - 35266

JO - Journal of Biological Chemistry

JF - Journal of Biological Chemistry

SN - 0021-9258

IS - 46

ER -