Silencing BRE expression in human umbilical cord perivascular (HUCPV) progenitor cells accelerates osteogenic and chondrogenic differentiation.
BRE is a multifunctional adapter protein involved in DNA repair, cell survival and stress response. To date, most studies of this protein have been focused in the tumor model. The role of BRE in stem cell biology has never been investigated. Therefore, we have used HUCPV progenitor cells to elucidate the function of BRE. HUCPV cells are multipotent fetal progenitor cells which possess the ability to differentiate into a multitude of mesenchymal cell lineages when chemically induced and can be more easily amplified in culture. In this study, we have established that BRE expression was normally expressed in HUCPV cells but become down-regulated when the cells were induced to differentiate. In addition, silencing BRE expression, using BRE-siRNAs, in HUCPV cells could accelerate induced chondrogenic and osteogenic differentiation. Hence, we postulated that BRE played an important role in maintaining the stemness of HUCPV cells. We used microarray analysis to examine the transcriptome of BRE-silenced cells. BRE-silencing negatively regulated OCT4, FGF5 and FOXO1A. BRE-silencing also altered the expression of epigenetic genes and components of the TGF-β/BMP and FGF signaling pathways which are crucially involved in maintaining stem cell self-renewal. Comparative proteomic profiling also revealed that BRE-silencing resulted in decreased expressions of actin-binding proteins. In sum, we propose that BRE acts like an adaptor protein that promotes stemness and at the same time inhibits the differentiation of HUCPV cells.
Stem Cell and Regeneration Thematic Research Programme, School of Biomedical Sciences, Chinese University of Hong Kong, Hong Kong, People's Republic of China.
Elve
E
Chen
Mei Kuen
MK
Tang
Yao
Y
Yao
Winifred Wing Yiu
WW
Yau
Lok Man
LM
Lo
Xuesong
X
Yang
Yiu Loon
YL
Chui
John
J
Chan
Kenneth Ka Ho
KK
Lee
D000818:Animals; D019485:Bone Morphogenetic Proteins / Q000378:metabolism; D002454:Cell Differentiation; D018925:Chemokines / Q000378:metabolism; D019902:Chondrocytes / Q000166:cytology / Q000378:metabolism; D020219:Chondrogenesis; D003598:Cytoskeletal Proteins / Q000378:metabolism; D044127:Epigenesis, Genetic; D005346:Fibroblast Growth Factors / Q000378:metabolism; D020868:Gene Silencing; D018398:Homeodomain Proteins / Q000378:metabolism; D006801:Humans; D051379:Mice; D039902:Multipotent Stem Cells / Q000166:cytology / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D050814:Octamer Transcription Factor-3 / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D010006:Osteoblasts / Q000166:cytology / Q000378:metabolism; D010012:Osteogenesis; D020543:Proteome / Q000378:metabolism; D040901:Proteomics; D034741:RNA, Small Interfering / Q000378:metabolism; D015398:Signal Transduction / Q000235:genetics; D013234:Stem Cells / Q000166:cytology* / Q000378:metabolism; D016212:Transforming Growth Factor beta / Q000378:metabolism; D014470:Umbilical Cord / Q000098:blood supply / Q000166:cytology*
C091514:BABAM2 protein, human; D019485:Bone Morphogenetic Proteins; D018925:Chemokines; D003598:Cytoskeletal Proteins; D018398:Homeodomain Proteins; D009419:Nerve Tissue Proteins; D050814:Octamer Transcription Factor-3; C494173:POU5F1 protein, human; D020543:Proteome; D034741:RNA, Small Interfering; D016212:Transforming Growth Factor beta; D005346:Fibroblast Growth Factors