RHO methylation matters: a role for isoprenylcysteine carboxylmethyltransferase in cell migration and adhesion.
Numerous proteins involved in diverse aspects of cell biology undergo a process of post-translational modification termed prenylation. The prenylation pathway consists of three enzymatic steps, the final of which is methylation of the carboxyl-terminal prenylcysteine formed in the first two steps by the enzyme isoprenylcysteine carboxylmethyltransferase (Icmt). Due to the prevalence of prenylated proteins in cancer biology, and the findings that several of the proteins are involved in processes controlling cell migration and adhesion, we sought to examine the role of Icmt - mediated methylation on cell behavior associated with metastasis. We found that inhibition of methylation reduces migration of the highly metastatic MDA-MB-231 breast cancer cell line. In addition, cell adhesion and cell spreading were also impaired by Icmt inhibition. Further investigation revealed that inhibition of Icmt significantly decreased the activation of both RhoA and Rac1, which are both prenylated proteins. The data obtained were consistent with the decreased activation being due to an increase in Rho GDP-dissociation inhibitor (GDI) binding by both proteins in the absence of their methylation. Importantly, the addition of exogenous RhoA or Rac1 to cells in which Icmt was inhibited was able to partially, but selectively, rescue directed and random migration, respectively. These results establish a role for Icmt-mediated methylation in cell migration, and point to specific prenylated proteins involved in this biology. The prenylation pathway has been targeted for oncogenic therapies, but the role of methylation in cell motility had been largely unexplored until now. The finding that methylation of Rho family members impacts on a specific component of their function provides an additional avenue through which to interrogate the biology of this important class of regulatory proteins.
Cushman
Ian
I
Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina, USA.
Casey
Patrick J
PJ
D002448:Cell Adhesion / Q000502:physiology*; D045744:Cell Line, Tumor / Q000737:chemistry; D002465:Cell Movement / Q000502:physiology*; D020730:Guanine Nucleotide Dissociation Inhibitors / Q000737:chemistry*; D006801:Humans; D008745:Methylation; D011485:Protein Binding; D011496:Protein Methyltransferases / Q000737:chemistry*; D017368:Protein Prenylation / Q000502:physiology; D011499:Protein Processing, Post-Translational / Q000502:physiology; D015398:Signal Transduction / Q000502:physiology; D020830:rac1 GTP-Binding Protein / Q000737:chemistry; D020741:rho GTP-Binding Proteins / Q000737:chemistry*; D062947:rho-Specific Guanine Nucleotide Dissociation Inhibitors; D020742:rhoA GTP-Binding Protein / Q000737:chemistry
D020730:Guanine Nucleotide Dissociation Inhibitors; D062947:rho-Specific Guanine Nucleotide Dissociation Inhibitors; D011496:Protein Methyltransferases; C056501:protein-S-isoprenylcysteine O-methyltransferase; D020830:rac1 GTP-Binding Protein; D020741:rho GTP-Binding Proteins; D020742:rhoA GTP-Binding Protein
Cancer Treat Rev. 2004 Nov;30(7):609-41
15531395
J Biol Chem. 2009 Oct 9;284(41):27964-27973
19651782
Blood. 2008 Aug 15;112(4):1357-65
18502828
Nature. 2002 Dec 12;420(6916):629-35
12478284
J Mol Biol. 2004 Oct 15;343(2):417-33
15451670
Cell. 2000 Feb 4;100(3):345-56
10676816
Oncogene. 1991 Apr;6(4):515-22
1903193
Nat Rev Cancer. 2007 Apr;7(4):295-308
17384584
J Biol Chem. 2005 May 13;280(19):18790-6
15647276
J Biol Chem. 2008 Sep 12;283(37):25150-25163
18614539
Annu Rev Biochem. 1996;65:241-69
8811180
Biochemistry. 2001 Aug 28;40(34):10007-13
11513578
Nat Chem Biol. 2006 Oct;2(10):518-28
16983387
J Clin Invest. 2004 Feb;113(4):513-5
14966560
J Biol Chem. 1997 Dec 26;272(52):33175-80
9407105
Cell Signal. 2000 Aug;12(8):515-24
11027944
Annu Rev Cell Biol. 1994;10:181-205
7888176
J Biol Chem. 1998 Jun 12;273(24):15030-4
9614111
Am J Physiol Lung Cell Mol Physiol. 2004 Dec;287(6):L1091-7
15286003
Proc Natl Acad Sci U S A. 1991 Aug 1;88(15):6442-6
1907371
Curr Opin Investig Drugs. 2002 Sep;3(9):1312-7
12498006
Mol Biol Cell. 2005 Apr;16(4):1606-16
15659645
Science. 1997 Mar 21;275(5307):1796-800
9065405
Circ Res. 2004 Feb 20;94(3):306-15
14699010
J Biol Chem. 1996 Mar 8;271(10):5289-92
8621375
Cancer Metastasis Rev. 2009 Jun;28(1-2):65-76
19160018
Sci STKE. 2004 Sep 07;2004(250):RE13
15367757
Circ Res. 2005 Jun 10;96(11):1152-60
15890975
Proc Natl Acad Sci U S A. 2005 Mar 22;102(12):4336-41
15784746
Curr Med Chem. 2008;15(15):1478-92
18537624
J Biol Chem. 2008 Jul 4;283(27):18678-84
18434300
Oncologist. 2006 Mar;11(3):306-15
16549815
J Clin Invest. 2004 Feb;113(4):539-50
14966563