title: Regulation of nucleocytoplasmic shuttling of Bruton's tyrosine kinase (Btk) through a novel SH3-dependent interaction with ankyrin repeat domain 54 (ANKRD54).
abstract: Bruton's tyrosine kinase (Btk), belonging to the Tec family of tyrosine kinases (TFKs), is essential for B-lymphocyte development. Abrogation of Btk signaling causes human X-linked agammaglobulinemia (XLA) and murine X-linked immunodeficiency (Xid). We employed affinity purification of Flag-tagged Btk, combined with tandem mass spectrometry, to capture and identify novel interacting proteins. We here characterize the interaction with ankryin repeat domain 54 protein (ANKRD54), also known as Lyn-interacting ankyrin repeat protein (Liar). While Btk is a nucleocytoplasmic protein, the Liar pool was found to shuttle at a higher rate than Btk. Importantly, our results suggest that Liar mediates nuclear export of both Btk and another TFK, Txk/Rlk. Liar-mediated Btk shuttling was enriched for activation loop, nonphosphorylated Btk and entirely dependent on Btk's SH3 domain. Liar also showed reduced binding to an aspartic acid phosphomimetic SH3 mutant. Three other investigated nucleus-located proteins, Abl, estrogen receptor β (ERβ), and transcription factor T-bet, were all unaffected by Liar. We mapped the interaction site to the C terminus of the Btk SH3 domain. A biotinylated, synthetic Btk peptide, ARDKNGQEGYIPSNYVTEAEDS, was sufficient for this interaction. Liar is the first protein identified that specifically influences the nucleocytoplasmic shuttling of Btk and Txk and belongs to a rare group of known proteins carrying out this activity in a Crm1-dependent manner.
authors.affiliation: Department of Laboratory Medicine, Clinical Research Center, Karolinska Institutet, Karolinska University Hospital Huddinge, Huddinge, Sweden.
authors.forename: Manuela O
authors.initials: MO
authors.lastname: Gustafsson
authors.forename: Alamdar
authors.initials: A
authors.lastname: Hussain
authors.forename: Dara K
authors.initials: DK
authors.lastname: Mohammad
authors.forename: Abdalla J
authors.initials: AJ
authors.lastname: Mohamed
authors.forename: Vivian
authors.initials: V
authors.lastname: Nguyen
authors.forename: Pavel
authors.initials: P
authors.lastname: Metalnikov
authors.forename: Karen
authors.initials: K
authors.lastname: Colwill
authors.forename: Tony
authors.initials: T
authors.lastname: Pawson
authors.forename: C I Edvard
authors.initials: CI
authors.lastname: Smith
authors.forename: Beston F
authors.initials: BF
authors.lastname: Nore
mesh_terms: D021581:Active Transport, Cell Nucleus; D000077329:Agammaglobulinaemia Tyrosine Kinase; D000595:Amino Acid Sequence; D000818:Animals; D017089:Ankyrin Repeat; D001483:Base Sequence; D019556:COS Cells; D002352:Carrier Proteins / Q000378:metabolism; D002460:Cell Line; D002522:Chlorocebus aethiops; D057809:HEK293 Cells; D006801:Humans; D019169:Jurkat Cells; D020014:K562 Cells; D051379:Mice; D008954:Models, Biological; D008969:Molecular Sequence Data; D041681:NIH 3T3 Cells; D025941:Protein Interaction Mapping; D011505:Protein-Tyrosine Kinases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D018909:src Homology Domains
chemical_list: D002352:Carrier Proteins; D011993:Recombinant Fusion Proteins; C540566:liar protein, mouse; C089848:Tec protein-tyrosine kinase; D011505:Protein-Tyrosine Kinases; D000077329:Agammaglobulinaemia Tyrosine Kinase; C000625949:BTK protein, human; C000625951:Btk protein, mouse