Modulated Binding of SATB1, a Matrix Attachment Region Protein, to the AT-Rich Sequence Flanking the Major Breakpoint Region of BCL2

• DOI: 10.1128/mcb.20.3.868-877.2000
• Publication Date: 2002-07-27T10:03:53Z
• Authors: Meera Ramakrishnan; Wen-Man Liu; Patricia A. DiCroce; Aleza Posner; Jian Zheng; Terumi Kohwi-Shig...; Theodore G. Kront...
• Keywords: Breakpoint; Scaffold/matrix attachment region

The t(14,18) chromosomal translocation that occurs in human follicular lymphoma constitutively activates the BCL2 gene and disrupts control of apoptosis.Interestingly, 70% translocations are confined to three 15-bp clusters positioned within a 150-bp region (major breakpoint or [MBR]) untranslated portion terminal exon 3. We analyzed DNA-protein interactions MBR, as these may play some role targeting this region.An 87-bp segment (87MBR) immediately 3 cluster was essential for interaction monitored with mobility shift assays.We further delineated core binding 87MBR: 33-bp, very AT-rich sequence highly conserved between mouse (37MBR).We have purified identified one factors matrix attachment (MAR) protein, SATB1, which is known bind sequences high propensity unwind.Additional nuclear extracts, we not yet characterized further, increased SATB1 affinity 37MBR target four-to fivefold.Specific activity displayed cell cycle regulation Jurkat T cells, while levels remained constant throughout cycle.Finally, demonstrated vivo strongly suggesting major MAR.We discuss potential consequences our observations both MBR fragility regulatory function.