PT  - JOURNAL ARTICLE
AU  - Aleksandar Kojic
AU  - Ana Cuadrado
AU  - Magali De Koninck
AU  - Miriam Rodríguez-Corsino
AU  - Gonzalo Gómez-López
AU  - François Le Dily
AU  - Marc A. Marti-Renom
AU  - Ana Losada
TI  - Distinct roles of cohesin-SA1 and cohesin-SA2 in 3D chromosome organization
AID  - 10.1101/166264
DP  - 2017 Jan 01
TA  - bioRxiv
PG  - 166264
4099  - http://biorxiv.org/content/early/2017/07/20/166264.short
4100  - http://biorxiv.org/content/early/2017/07/20/166264.full
AB  - In addition to mediating sister chromatid cohesion, cohesin plays a central role in DNA looping and segmentation of the genome into contact domains (TADs). Two variant cohesin complexes that contain either STAG/SA1 or SA2 are present in all cell types. Here we addressed their specific contribution to genome architecture in non-transformed human cells. We found that cohesin-SA1 drives stacking of cohesin rings at CTCF-bound sites and thereby contributes to the stabilization and preservation of TAD boundaries. In contrast, a more dynamic cohesin-SA2 promotes cell type-specific contacts between enhancers and promoters within TADs independently of CTCF. SA2 loss, a condition frequently observed in cancer cells, results in increased intra-TAD interactions, likely altering the expression of key cell identity genes.