Peloruside A does not bind to the taxoid site on beta-tubulin and retains its activity in multidrug-resistant cell lines.
Peloruside A (peloruside), a microtubule-stabilizing agent from a marine sponge, is less susceptible than paclitaxel to multidrug resistance arising from overexpression of the P-glycoprotein efflux pump and is not affected by mutations that affect the taxoid binding site of beta-tubulin. In vitro studies with purified tubulin indicate that peloruside directly induces tubulin polymerization in the absence of microtubule-associated proteins. Competition for binding between peloruside, paclitaxel, and laulimalide revealed that peloruside binds to a different site on tubulin to paclitaxel. Moreover, laulimalide was able to displace peloruside, indicating that peloruside and laulimalide may compete for the same or overlapping binding sites. It was concluded that peloruside and laulimalide have binding properties that are distinct from other microtubule-stabilizing compounds currently under investigation.
Gaitanos
Thomas N
TN
School of Biological Sciences,Victoria University of Wellington, PO Box 600, Wellington, New Zealand.
Buey
Rubén M
RM
Díaz
J Fernando
JF
Northcote
Peter T
PT
Teesdale-Spittle
Paul
P
Andreu
José M
JM
Miller
John H
JH
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000502:physiology; D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000378:metabolism / Q000494:pharmacology; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000378:metabolism* / Q000494:pharmacology; D016466:CHO Cells / Q000187:drug effects / Q000378:metabolism; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D006224:Cricetinae; D018432:Drug Resistance, Multiple; D019008:Drug Resistance, Neoplasm; D005260:Female; D019450:Genes, MDR / Q000502:physiology; D006801:Humans; D007783:Lactones / Q000378:metabolism* / Q000494:pharmacology; D008024:Ligands; D018942:Macrolides; D013058:Mass Spectrometry; D008870:Microtubules / Q000187:drug effects* / Q000378:metabolism; D009154:Mutation; D010051:Ovarian Neoplasms / Q000378:metabolism / Q000473:pathology; D017239:Paclitaxel / Q000378:metabolism / Q000494:pharmacology; D043823:Taxoids / Q000378:metabolism* / Q000494:pharmacology; D014404:Tubulin / Q000235:genetics / Q000378:metabolism*
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000972:Antineoplastic Agents, Phytogenic; D019086:Bridged Bicyclo Compounds, Heterocyclic; D007783:Lactones; D008024:Ligands; D018942:Macrolides; D043823:Taxoids; D014404:Tubulin; C117305:laulimalide; C414085:peloruside A; D017239:Paclitaxel