title: TNF ligands: is TALL-1 a trimer or a virus-like cluster?
abstract: Native TALL-1 (B-cell activation factor, BAFF; also known as BlyS) was initially described as a homotrimer, but Liu and colleagues claim that it is a 60-subunit complex on the basis of their results from X-ray crystallography and size-exclusion chromatography. They consider TALL-1 60-mers to be the biologically active form, and the arrangement of the 60-mers resembles that of the capsid of satellite tobacco necrosis virus. Here we show that active TALL-1 is trimeric under normal physiological conditions and that formation of higher-order oligomers is an artefact of tagging the amino terminus of the protein with a histidine tag.
authors.affiliation: Xencor, Monrovia, California 91016, USA. ezhukovsky@xencor.com
authors.forename: Eugene A
authors.initials: EA
authors.lastname: Zhukovsky
authors.forename: Jie-Oh
authors.initials: JO
authors.lastname: Lee
authors.forename: Michael
authors.initials: M
authors.lastname: Villegas
authors.forename: Cheryl
authors.initials: C
authors.lastname: Chan
authors.forename: Seung
authors.initials: S
authors.lastname: Chu
authors.forename: Cameron
authors.initials: C
authors.lastname: Mroske
mesh_terms: D016477:Artifacts; D053264:B-Cell Activating Factor; D001402:B-Lymphocytes / Q000166:cytology / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002850:Chromatography, Gel; D018360:Crystallography, X-Ray; D006863:Hydrogen-Ion Concentration; D008565:Membrane Proteins / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism* / Q000494:pharmacology; D020836:Protein Structure, Quaternary; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology; D015203:Reproducibility of Results; D014409:Tumor Necrosis Factor-alpha / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism* / Q000494:pharmacology
chemical_list: D053264:B-Cell Activating Factor; D008565:Membrane Proteins; D011993:Recombinant Fusion Proteins; D014409:Tumor Necrosis Factor-alpha