TY - JOUR
T1 - SPOP is essential for DNA replication licensing through maintaining translation of CDT1 and CDC6 in HaCaT cells
AU - Sanada, Sayoko
AU - Maekawa, Masashi
AU - Tate, Sota
AU - Nakaoka, Hiroki
AU - Fujisawa, Yasuhiro
AU - Sayama, Koji
AU - Higashiyama, Shigeki
N1 - Funding Information:
We thank Ms. Mami Chosei, Ms. Teruko Tsuda, Mr. Kenji Kameda, Dr. Tomohisa Sakaue, Dr. Masamoto Murakami, Dr. Hideki Mori, and Dr. Hiroyuki Takeda from Ehime University and Dr. Jun Nakayama from National Cancer Center Research Institute for providing their technical assistance. This study was supported by the Division of Analytical Bio-Medicine, Advanced Research Support Center (ADRES), Ehime University. This work was supported by JSPS KAKENHI Grant Number 20K18413 to S.S.; JSPS KAKENHI Grant Number 21K07126 , 21H00286 , and Nakatomi Foundation , KOSE Cosmetology Research Foundation and Suzuken Memorial Foundation to M.M.; JSPS KAKENHI Grant Number 19K10030 to H.N.; Takeda Science Foundation to Proteo-Science Center ; and JSPS KAKENHI Grant Number 21K18262 and The Naito Foundation to S.H.
Publisher Copyright:
© 2023 The Authors
PY - 2023/4/9
Y1 - 2023/4/9
N2 - Speckle-type pox virus and zinc finger (POZ) protein (SPOP), a substrate recognition receptor for the cullin-3/RING ubiquitin E3 complex, leads to the ubiquitination of >40 of its target substrates. Since a variety of point mutations in the substrate-binding domain of SPOP have been identified in cancers, including prostate and endometrial cancers, the pathological roles of those cancer-associated SPOP mutants have been extensively elucidated. In this study, we evaluated the cellular functions of wild-type SPOP in non-cancerous human keratinocyte-derived HaCaT cells expressing wild-type SPOP gene. SPOP knockdown using siRNA in HaCaT cells dramatically reduced cell growth and arrested their cell cycles at G1/S phase. The expression of DNA replication licensing factors CDT1 and CDC6 in HaCaT cells drastically decreased on SPOP knockdown as their translation was inhibited. CDT1 and CDC6 downregulation induced p21 expression without p53 activation. Our results suggest that SPOP is essential for DNA replication licensing in non-cancerous keratinocyte HaCaT cells.
AB - Speckle-type pox virus and zinc finger (POZ) protein (SPOP), a substrate recognition receptor for the cullin-3/RING ubiquitin E3 complex, leads to the ubiquitination of >40 of its target substrates. Since a variety of point mutations in the substrate-binding domain of SPOP have been identified in cancers, including prostate and endometrial cancers, the pathological roles of those cancer-associated SPOP mutants have been extensively elucidated. In this study, we evaluated the cellular functions of wild-type SPOP in non-cancerous human keratinocyte-derived HaCaT cells expressing wild-type SPOP gene. SPOP knockdown using siRNA in HaCaT cells dramatically reduced cell growth and arrested their cell cycles at G1/S phase. The expression of DNA replication licensing factors CDT1 and CDC6 in HaCaT cells drastically decreased on SPOP knockdown as their translation was inhibited. CDT1 and CDC6 downregulation induced p21 expression without p53 activation. Our results suggest that SPOP is essential for DNA replication licensing in non-cancerous keratinocyte HaCaT cells.
KW - CDC6
KW - CDT1
KW - DNA replication licensing
KW - SPOP
KW - Translation
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U2 - 10.1016/j.bbrc.2023.02.012
DO - 10.1016/j.bbrc.2023.02.012
M3 - Article
C2 - 36791496
AN - SCOPUS:85148078654
SN - 0006-291X
VL - 651
SP - 30
EP - 38
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
ER -
