Project description:Aneuploidy, an uneven number of chromosomes, leads to severe developmental defects in mammals and is also a hallmark of cancer. However, whether aneuploidy is a driving cause or a consequence of tumor formation remains controversial. Paradoxically, existing studies based on aneuploid yeast and mouse fibroblasts have shown that aneuploidy is usually detrimental to cellular fitness. Here, we examined the effects of aneuploidy on mouse embryonic stem cells. Using a novel genetic scheme, we generated a series of aneuploid cell lines that each carries an extra copy of single chromosomes and then characterized the traits shared by these cell lines. All the aneuploid cell lines had rapid proliferation rates and enhanced colony formation efficiencies. They were less dependent on growth factors for self-renewal and showed a reduced capacity to differentiate in vitro. Moreover, xenografted aneuploid stem cells formed teratomas more efficiently, with features of neoplastic progression. These findings demonstrate that aneuploidy enhances the self-renewal capacities of stem cells and reduces their differentiation abilities.
Project description:Comparative genomic hybridization (CGH) analysis of androgenetic haploid embryonic stem cells was done with 129/Sv male mouse kidney genomic DNA as reference. The results revealed no consistent copy number variations (CNVs) among the examined cell lines (AH129-5, AH129-N1 and AH129-NC1), except for the global difference on the X chromosome to the male control.
Project description:Comparative genomic hybridization (CGH) analysis of androgenetic haploid embryonic stem cells was done with 129/Sv male mouse kidney genomic DNA as reference. The results revealed no consistent copy number variations (CNVs) among the examined cell lines (AH129-5, AH129-N1 and AH129-NC1), except for the global difference on the X chromosome to the male control. Genomic DNA of FACS sorted G0/G1 stage ahES cells was compared with 129/Sv male mouse kidney genomic DNA reference by the NimbleGen Mouse CGH 3x720K Whole-Genome Tiling Array (Build MM9) [100718_MM9_WG_CGH_HX3]
Project description:Background:Human aneuploidy is the leading cause of early pregnancy loss, mental retardation, and multiple congenital anomalies. Due to the high mortality associated with aneuploidy, the pathophysiological mechanisms of aneuploidy syndrome remain largely unknown. Previous studies focused mostly on whether dosage compensation occurs, and the next generation transcriptomics sequencing technology RNA-seq is expected to eventually uncover the mechanisms of gene expression regulation and the related pathological phenotypes in human aneuploidy. Results:Using next generation transcriptomics sequencing technology RNA-seq, we profiled the transcriptomes of four human aneuploid induced pluripotent stem cell (iPSC) lines generated from monosomy X (Turner syndrome), trisomy 8 (Warkany syndrome 2), trisomy 13 (Patau syndrome), and partial trisomy 11:22 (Emanuel syndrome) as well as two umbilical cord matrix iPSC lines as euploid controls to examine how phenotypic abnormalities develop with aberrant karyotype. A total of 466 M (50-bp) reads were obtained from the six iPSC lines, and over 13,000 mRNAs were identified by gene annotation. Global analysis of gene expression profiles and functional analysis of differentially expressed (DE) genes were implemented. Over 5000 DE genes are determined between aneuploidy and euploid iPSCs respectively while 9 KEGG pathways are overlapped enriched in four aneuploidy samples. Conclusions:Our results demonstrate that the extra or missing chromosome has extensive effects on the whole transcriptome. Functional analysis of differentially expressed genes reveals that the genes most affected in aneuploid individuals are related to central nervous system development and tumorigenesis. Four aneuploid iPSC (trisomy 8, trisomy 13, partial trisomy 11:22, monosomy X) and two euploid iPSC mRNA profiles were generated by deep sequencing, using SOLiD v3 platform. Gene expression values were compared.
Project description:Aneuploidy, an uneven number of chromosomes, leads to severe developmental defects in mammals and is also a hallmark of cancer. However, whether aneuploidy is a driving cause or a consequence of tumor formation remains controversial. Paradoxically, existing studies based on aneuploid yeast and mouse fibroblasts have shown that aneuploidy is usually detrimental to cellular fitness. Here, we examined the effects of aneuploidy on mouse embryonic stem cells. Using a novel genetic scheme, we generated a series of aneuploid cell lines that each carries an extra copy of single chromosomes and then characterized the traits shared by these cell lines. All the aneuploid cell lines had rapid proliferation rates and enhanced colony formation efficiencies. They were less dependent on growth factors for self-renewal and showed a reduced capacity to differentiate in vitro. Moreover, xenografted aneuploid stem cells formed teratomas more efficiently, with features of neoplastic progression. These findings demonstrate that aneuploidy enhances the self-renewal capacities of stem cells and reduces their differentiation abilities.
Project description:Background:Human aneuploidy is the leading cause of early pregnancy loss, mental retardation, and multiple congenital anomalies. Due to the high mortality associated with aneuploidy, the pathophysiological mechanisms of aneuploidy syndrome remain largely unknown. Previous studies focused mostly on whether dosage compensation occurs, and the next generation transcriptomics sequencing technology RNA-seq is expected to eventually uncover the mechanisms of gene expression regulation and the related pathological phenotypes in human aneuploidy. Results:Using next generation transcriptomics sequencing technology RNA-seq, we profiled the transcriptomes of four human aneuploid induced pluripotent stem cell (iPSC) lines generated from monosomy X (Turner syndrome), trisomy 8 (Warkany syndrome 2), trisomy 13 (Patau syndrome), and partial trisomy 11:22 (Emanuel syndrome) as well as two umbilical cord matrix iPSC lines as euploid controls to examine how phenotypic abnormalities develop with aberrant karyotype. A total of 466 M (50-bp) reads were obtained from the six iPSC lines, and over 13,000 mRNAs were identified by gene annotation. Global analysis of gene expression profiles and functional analysis of differentially expressed (DE) genes were implemented. Over 5000 DE genes are determined between aneuploidy and euploid iPSCs respectively while 9 KEGG pathways are overlapped enriched in four aneuploidy samples. Conclusions:Our results demonstrate that the extra or missing chromosome has extensive effects on the whole transcriptome. Functional analysis of differentially expressed genes reveals that the genes most affected in aneuploid individuals are related to central nervous system development and tumorigenesis.