BTG2 antiproliferative protein interacts with the human CCR4 complex existing in vivo in three cell-cycle-regulated forms
2003
The yeast CCR4-NOT complex exists in two forms (1.0 and 1.9 MDa) that share
several common subunits, including yCCR4, yCAF1 and five NOT proteins
(NOT1-5). Here, we report that different complexes containing mammalian
homologs of CCR4-NOT subunits exist in mammalian cells, with estimated sizes
of ∼1.9 MDa, ∼1 MDa and ∼650 kDa, and that BTG2, a member of a
protein family with antiproliferative functions, can associate with these
complexes. Immunoprecipitation and gel filtration experiments established that
BTG2 interacts in vivo with hCCR4 protein via hCAF1 and hPOP2. Moreover, we
show that hCCR4, as well as hCAF1 and BTG2, modulate the transcription
regulation mediated by ERα. Finally, we demonstrate that the cellular
localization of hCAF1 and the cell content in hCAF1-containing complexes
change as cells progress from quiescence to S phase. These findings suggest
that the different regulatory pathways in which hCAF1 is involved, notably
transcription regulation and mRNA turnover, may occur through distinct CCR4
complexes in the course of cell-cycle progression.
Keywords:
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
32
References
56
Citations
NaN
KQI