@article {38584, title = {CTCF binding site sequence differences are associated with unique regulatory and functional trends during embryonic stem cell differentiation}, journal = {Nucleic Acids ResNucleic Acids ResNucleic Acids Res}, volume = {42}, number = {2}, year = {2014}, note = {Plasschaert, Robert N
Vigneau, Sebastien
Tempera, Italo
Gupta, Ravi
Maksimoska, Jasna
Everett, Logan
Davuluri, Ramana
Mamorstein, Ronen
Lieberman, Paul M
Schultz, David
Hannenhalli, Sridhar
Bartolomei, Marisa S
eng
K99AI099153/AI/NIAID NIH HHS/
P30 CA10815/CA/NCI NIH HHS/
R01 CA140652/CA/NCI NIH HHS/
R01-GM052880/GM/NIGMS NIH HHS/
R01CA140652/CA/NCI NIH HHS/
R01GM085226/GM/NIGMS NIH HHS/
R01HD042026/HD/NICHD NIH HHS/
T32GM008216/GM/NIGMS NIH HHS/
Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov{\textquoteright}t
England
2013/10/15 06:00
Nucleic Acids Res. 2014 Jan;42(2):774-89. doi: 10.1093/nar/gkt910. Epub 2013 Oct 10.}, month = {Jan}, pages = {774-89}, abstract = {CTCF (CCCTC-binding factor) is a highly conserved multifunctional DNA-binding protein with thousands of binding sites genome-wide. Our previous work suggested that differences in CTCF{\textquoteright}s binding site sequence may affect the regulation of CTCF recruitment and its function. To investigate this possibility, we characterized changes in genome-wide CTCF binding and gene expression during differentiation of mouse embryonic stem cells. After separating CTCF sites into three classes (LowOc, MedOc and HighOc) based on similarity to the consensus motif, we found that developmentally regulated CTCF binding occurs preferentially at LowOc sites, which have lower similarity to the consensus. By measuring the affinity of CTCF for selected sites, we show that sites lost during differentiation are enriched in motifs associated with weaker CTCF binding in vitro. Specifically, enrichment for T at the 18(th) position of the CTCF binding site is associated with regulated binding in the LowOc class and can predictably reduce CTCF affinity for binding sites. Finally, by comparing changes in CTCF binding with changes in gene expression during differentiation, we show that LowOc and HighOc sites are associated with distinct regulatory functions. Our results suggest that the regulatory control of CTCF is dependent in part on specific motifs within its binding site.}, keywords = {*Gene Expression Regulation, *Regulatory Elements, Transcriptional, Animals, Binding Sites, Cell Differentiation/*genetics, Cells, Cultured, Embryonic Stem Cells/cytology/*metabolism, Mice, Nucleotide Motifs, Protein Binding, Repressor Proteins/*metabolism}, isbn = {1362-4962 (Electronic)
0305-1048 (Linking)}, author = {Plasschaert, R. N. and Vigneau, S. and Tempera, I. and Gupta, R. and Maksimoska, J. and Everett, L. and Davuluri, R. and Mamorstein, R. and Lieberman, P. M. and Schultz, D. and Sridhar Hannenhalli and Bartolomei, M. S.} } @article {38582, title = {Derepression of Cancer/testis antigens in cancer is associated with distinct patterns of DNA hypomethylation}, journal = {BMC CancerBMC CancerBMC Cancer}, volume = {13}, year = {2013}, note = {Kim, Robert
Kulkarni, Prakash
Hannenhalli, Sridhar
eng
R01 GM100335/GM/NIGMS NIH HHS/
R01GM100335/GM/NIGMS NIH HHS/
Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov{\textquoteright}t
England
2013/03/26 06:00
BMC Cancer. 2013 Mar 22;13:144. doi: 10.1186/1471-2407-13-144.}, pages = {144}, abstract = {BACKGROUND: The Cancer/Testis Antigens (CTAs) are a heterogeneous group of proteins whose expression is typically restricted to the testis. However, they are aberrantly expressed in most cancers that have been examined to date. Broadly speaking, the CTAs can be divided into two groups: the CTX antigens that are encoded by the X-linked genes and the non-X CT antigens that are encoded by the autosomes. Unlike the non-X CTAs, the CTX antigens form clusters of closely related gene families and their expression is frequently associated with advanced disease with poorer prognosis. Regardless however, the mechanism(s) underlying their selective derepression and stage-specific expression in cancer remain poorly understood, although promoter DNA demethylation is believed to be the major driver. METHODS: Here, we report a systematic analysis of DNA methylation profiling data from various tissue types to elucidate the mechanism underlying the derepression of the CTAs in cancer. We analyzed the methylation profiles of 501 samples including sperm, several cancer types, and their corresponding normal somatic tissue types. RESULTS: We found strong evidence for specific DNA hypomethylation of CTA promoters in the testis and cancer cells but not in their normal somatic counterparts. We also found that hypomethylation was clustered on the genome into domains that coincided with nuclear lamina-associated domains (LADs) and that these regions appeared to be insulated by CTCF sites. Interestingly, we did not observe any significant differences in the hypomethylation pattern between the CTAs without CpG islands and the CTAs with CpG islands in the proximal promoter. CONCLUSION: Our results corroborate that widespread DNA hypomethylation appears to be the driver in the derepression of CTA expression in cancer and furthermore, demonstrate that these hypomethylated domains are associated with the nuclear lamina-associated domains (LADS). Taken together, our results suggest that wide-spread methylation changes in cancer are linked to derepression of germ-line-specific genes that is orchestrated by the three dimensional organization of the cancer genome.}, keywords = {*DNA Methylation, *Gene Expression Regulation, Neoplastic, *Genes, X-Linked, Antigens, Neoplasm/*genetics, Binding Sites, Cluster Analysis, CpG Islands, Gene Expression Profiling, HUMANS, Male, Neoplasms/*genetics/*metabolism, Promoter Regions, Genetic, Protein Binding, Protein Interaction Domains and Motifs, Testis/*metabolism}, isbn = {1471-2407 (Electronic)
1471-2407 (Linking)}, author = {Kim, R. and Kulkarni, P. and Sridhar Hannenhalli} }