Identification of the p28 subunit of eukaryotic initiation factor 3(eIF3k) as a new interaction partner of cyclin D3.
Cyclin D3 is found to play a crucial role not only in progression through the G1 phase as a regulatory subunit of cyclin-dependent kinase 4 (CDK 4) and CDK 6, but also in many other aspects such as cell cycle, cell differentiation, transcriptional regulation and apoptosis. In this work, we screened a human fetal liver cDNA library using human cyclin D3 as bait and identified human eukaryotic initiation factor 3 p28 protein (eIF3k) as a partner of cyclin D3. The association of cyclin D3 with eIF3k was further confirmed by in vitro binding assay, in vivo coimmunoprecipitation, and confocal microscopic analysis. We found that cyclin D3 specifically interacted with eIF3k through its C-terminal domain. Immunofluorescence experiments showed that eIF3k distributed both in nucleus and cytoplasm and colocalized with cyclin D3. In addition, the cellular translation activity in HeLa cells was upregulated by cyclin D3 overexpression and the mRNA levels are constant. These data provide a new clue to our understanding of the cellular function of cyclin D3.
State key laboratory of Genetic Engineering and Gene Research Center, Shanghai Medical College of Fudan University, Shanghai 200032, PR China.
Xiaoyun
X
Shen
Yanzhong
Y
Yang
Weicheng
W
Liu
Maoyun
M
Sun
Jianhai
J
Jiang
Hongliang
H
Zong
Jianxin
J
Gu
D000595:Amino Acid Sequence; D001665:Binding Sites; D056743:Cyclin D3; D016213:Cyclins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D039621:Eukaryotic Initiation Factor-3 / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D008969:Molecular Sequence Data; D011485:Protein Binding; D014176:Protein Biosynthesis; D021122:Protein Subunits / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D021381:Protein Transport; D016415:Sequence Alignment; D020798:Two-Hybrid System Techniques
C534696:CCND3 protein, human; D056743:Cyclin D3; D016213:Cyclins; D039621:Eukaryotic Initiation Factor-3; D021122:Protein Subunits