Structural Basis for the Cytoskeletal Association of Bcr-Abl/c-Abl

13 Pages·2012·0.92 MB·English

MolecularCell,Vol.19,461–473,August19,2005,Copyright©2005byElsevierInc. DOI10.1016/j.molcel.2005.06.030
Structural Basis for the Cytoskeletal
Association of Bcr-Abl/c-Abl
OliverHantschel,1,2,5SilkeWiesner,3,5,7 activitycomparedtothekinaseactivityofc-Abl,which
ThomasGüttler,4,6CameronD.Mackereth,3,6 is effectively autoinhibited by different intramolecular
LilyL.RemsingRix,1,2,6ZsuzsannaMikes,2 interactions (Raitano et al., 1997; Hantschel and Su-
JanaDehne,2DirkGörlich,4MichaelSattler,3,* perti-Furga, 2004). Inhibition of the tyrosine kinase
andGiulioSuperti-Furga1,2,* activityofBcr-Ablbythesmall-moleculeinhibitorImati-
1CenterforMolecularMedicineoftheAustrian nib/Gleevec has become a paradigm for modern tar-
AcademyofSciences geted cancer therapy, but emerging cases of drug re-
Lazarettgasse19/3 sistance create a demand for additional therapeutic
1090Vienna intervention strategies (Druker, 2004; Sawyers, 2004).
Austria Bcr-Ablispredominantlylocalizedtothecytoplasmof
2DevelopmentalBiologyProgramme cells, where it activates different signal transduction
3StructuralandComputationalBiologyProgramme pathways, leading to cell proliferation (McWhirter and
EuropeanMolecularBiologyLaboratory Wang,1991,1993;Steelmanetal.,2004).However,re-
Meyerhofstrasse1 localization to the nucleus can be achieved by either
69117Heidelberg combination of pharmacological treatment or geno-
Germany toxicstressresultinginalterationofitsgrowth-promot-
4ZMBH ing properties (Dierov et al., 2004; Vigneri and Wang,
UniversityofHeidelberg 2001). The cellular form c-Abl localizes to varying de-
ImNeuenheimerFeld282 greesto boththecytoplasm andthe nucleusdepend-
69120Heidelberg ing on tissue type and environmental cues and is
Germany thought to shuttle between these two compartments
(VanEttenetal.,1989;Wetzleretal.,1993;Renshawet
al.,1988;Taageperaetal.,1998).
Bcr-Abl spans more than 2000 amino acid residues
Summary
andcomprisesacomplexarrayofmultipleprotein-pro-
tein interaction and signaling domains, including a cen-
TheBcr-Abltyrosinekinasecausesdifferentformsof
trallylocatedSH3-SH2-tyrosinekinasedomainmodule
leukemiainhumans.Dependingonitspositionwithin
(Figure1A).Theproposedlocalizationdeterminantsare
thecell,Bcr-Abldifferentiallyaffectscellulargrowth.
allfoundintheC-terminallastexonregionthatiscom-
However, no structural and molecular details for the
mon to both Bcr-Abl and c-Abl. These include three
anticipated localization determinants are available.
nuclearlocalizationsignals(NLSs)(Wenetal.,1996),a
We presentthe NMR structure ofthe F-actin binding
leucine-richNES(Taageperaetal.,1998),andanFABD
domain(FABD)ofBcr-Ablanditscellularcounterpart
(McWhirterandWang,1993;VanEttenetal.,1994)(Fig-
c-Abl. The FABD forms a compact left-handed four-
ure 1A). Although major insight into the regulatory
helixbundleinsolution.Weshowthatthenuclearex-
mechanismsofc-Ablautoinhibitioncouldbeprovided
portsignal(NES)previouslyreportedinthisregionis
bysolvingthestructureoftheSH3-SH2-kinasedomain
partofthehydrophobiccoreandnonfunctionalinthe
fragment,stillonlyaboutone-thirdofBcr-Abl’sprotein
intactprotein.Incontrast,wecouldidentifythecriti-
cal residues of helix (cid:1)III that are responsible for structureisknowntodate(HantschelandSuperti-Furga,
2004;Harrison,2003;Nagaretal.,2003;Hantscheletal.,
F-actinbindingandcytoskeletalassociation.Wepro-
2003). To explore the molecular basis of Bcr-Abl/c-Abl
posethattheseinteractionsrepresentamajordeter-
localization, we solved the structure of the FABD and
minantforbothBcr-Ablandc-Abllocalization.
studieditsmolecularfunction.Ourdataprovidestruc-
turalinsightsintoalocalizationdeterminantofBcr-Abl/
Introduction
c-Abl.
Expression of Bcr-Abl, the oncogenic counterpart of
ResultsandDiscussion
thetyrosinekinasec-AblandtheoutcomeofthePhila-
delphiachromosometranslocation(t[9;22]),isthebasis
NMRStructureoftheFABD
for all cases of chronic myelogenous leukemia (CML)
We determined the three-dimensional (3D) solution
and a subset of acute lymphocytic leukemia (ALL)
structureoftheFABD(correspondingtoresidues1026–
(Wong and Witte, 2004). The predominant distinguish-
1149 of human c-Abl spliceform 1b) by heteronuclear
ingfeatureofBcr-Ablisitshighleveloftyrosinekinase
NMR spectroscopy (Figures 1B and 1C and Table 1).
ThisdomainalsoincludesthepreviouslyproposedNES
*Correspondence: [email protected] (G.S.-F.); sattler@ (residues1109–1118)(Taageperaetal.,1998).
embl.de(M.S.). TheorderedregionoftheFABD,whichencompasses
5Theseauthorscontributedequallytothiswork.
residues1047–1149,isamonomerinsolutionandfolds
6Theseauthorscontributedequallytothiswork.
as a compact bundle of four antiparallel α helices,
7Presentaddress:StructuralBiologyandBiochemistry,Hospitalfor
SickChildren,555UniversityAvenue,Toronto,Ontario,M5G1X8, which are arranged in a left-handed topology (Figures
Canada. 1B and 1C). A predominantly aliphatic core formed by