title: Asymmetric proteasome segregation as a mechanism for unequal partitioning of the transcription factor T-bet during T lymphocyte division.
abstract: Polarized segregation of proteins in T cells is thought to play a role in diverse cellular functions including signal transduction, migration, and directed secretion of cytokines. Persistence of this polarization can result in asymmetric segregation of fate-determining proteins during cell division, which may enable a T cell to generate diverse progeny. Here, we provide evidence that a lineage-determining transcription factor, T-bet, underwent asymmetric organization in activated T cells preparing to divide and that it was unequally partitioned into the two daughter cells. This unequal acquisition of T-bet appeared to result from its asymmetric destruction during mitosis by virtue of concomitant asymmetric segregation of the proteasome. These results suggest a mechanism by which a cell may unequally localize cellular activities during division, thereby imparting disparity in the abundance of cell fate regulators in the daughter cells.
authors.affiliation: Abramson Family Cancer Research Institute and Department of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA. changj@ucsd.edu
authors.forename: John T
authors.initials: JT
authors.lastname: Chang
authors.forename: Maria L
authors.initials: ML
authors.lastname: Ciocca
authors.forename: Ichiko
authors.initials: I
authors.lastname: Kinjyo
authors.forename: Vikram R
authors.initials: VR
authors.lastname: Palanivel
authors.forename: Courtney E
authors.initials: CE
authors.lastname: McClurkin
authors.forename: Caitlin S
authors.initials: CS
authors.lastname: Dejong
authors.forename: Erin C
authors.initials: EC
authors.lastname: Mooney
authors.forename: Jiyeon S
authors.initials: JS
authors.lastname: Kim
authors.forename: Natalie C
authors.initials: NC
authors.lastname: Steinel
authors.forename: Jane
authors.initials: J
authors.lastname: Oliaro
authors.forename: Catherine C
authors.initials: CC
authors.lastname: Yin
authors.forename: Bogdan I
authors.initials: BI
authors.lastname: Florea
authors.forename: Herman S
authors.initials: HS
authors.lastname: Overkleeft
authors.forename: Leslie J
authors.initials: LJ
authors.lastname: Berg
authors.forename: Sarah M
authors.initials: SM
authors.lastname: Russell
authors.forename: Gary A
authors.initials: GA
authors.lastname: Koretzky
authors.forename: Martha S
authors.initials: MS
authors.lastname: Jordan
authors.forename: Steven L
authors.initials: SL
authors.lastname: Reiner
mesh_terms: D000818:Animals; D016764:Cell Polarity; D002478:Cells, Cultured; D051379:Mice; D008810:Mice, Inbred C57BL; D008938:Mitosis; D010766:Phosphorylation; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism*; D020825:T-Box Domain Proteins / Q000276:immunology* / Q000378:metabolism; D013601:T-Lymphocytes / Q000166:cytology* / Q000201:enzymology / Q000276:immunology*; D000098815:T-bet Transcription Factor
chemical_list: D020825:T-Box Domain Proteins; D000098815:T-bet Transcription Factor; D046988:Proteasome Endopeptidase Complex