Chromatin-related proteins in pluripotent mouse embryonic stem cells are downregulated after removal of leukemia inhibitory factor.
Embryonic stem (ES) cells have generated enormous interest due to their capacity to self-renew and the potential for growing many different cell types in vitro. Leukemia inhibitory factor (LIF), bone morphogenetic proteins, octamer-binding protein 3 or 4, and Nanog are important factors in the maintenance of pluripotency in mouse ES cells. However, the mechanisms by which these factors regulate the pluripotency remain poorly understood. To identify other proteins involved in this process, we did a proteomic analysis of mouse ES cells that were cultured in the presence or absence of LIF. More than 100 proteins were found to be involved specifically in either the differentiation process or the maintenance of undifferentiated state. Among these, chromatin-related proteins were identified as the major proteins in nuclear extracts of undifferentiated cells. Analysis with real-time RT-PCR revealed that enrichment of these proteins in pluripotent ES cells was regulated at the transcriptional levels. These results suggest that specific chromatin-related proteins may be involved in maintaining the unique properties of pluripotent ES cells.
Kurisaki
Akira
A
The Institute for Enzyme Research, University of Tokushima, 3-18-15, Kuramoto, Tokushima 770-8503, Japan.
Hamazaki
Tatsuo S
TS
Okabayashi
Koji
K
Iida
Tetsuo
T
Nishine
Tsutomu
T
Chonan
Ritsu
R
Kido
Hiroshi
H
Tsunasawa
Susumu
S
Nishimura
Osamu
O
Asashima
Makoto
M
Sugino
Hiromu
H
D000818:Animals; D002478:Cells, Cultured; D002843:Chromatin / Q000502:physiology*; D015536:Down-Regulation; D004622:Embryo, Mammalian / Q000166:cytology / Q000378:metabolism*; D015850:Interleukin-6 / Q000378:metabolism*; D053605:Leukemia Inhibitory Factor; D051379:Mice; D039904:Pluripotent Stem Cells / Q000166:cytology / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
D002843:Chromatin; D015850:Interleukin-6; D053605:Leukemia Inhibitory Factor; C507838:Lif protein, mouse