Similar Datasets
Project description:Immunoglobulin heavy chain locus (Igh) VH, D, and JH gene segments are developmentally assembled into V(D)J exons. RAG endonuclease initiates V(D)J recombination by binding a JH-recombination signal sequence (RSS) within a chromatin-based recombination center (RC) and then, in an orientation-dependent process, scans upstream D-containing chromatin presented by cohesin-mediated loop extrusion for convergent D-RSSs to initiate DJH-RC formation. In primary pro-B cells, 100s of upstream VH-associated RSSs, embedded in convergent orientation to the DJH-RC-RSS, gain proximity to the DJH-RC for VH-to-DJH joining via a mechanistically-undefined VH-locus contraction process. Here, we report that a 2.4 mega-base VH locus inversion in primary pro-B cells nearly abrogates rearrangements of normally convergent VH-RSSs and cryptic RSSs, even though locus contraction per se is maintained. Moreover, this inversion activated rearrangement of both cryptic VH-locus RSSs normally in the opposite orientation and, unexpectedly, of normally-oriented cryptic RSSs within multiple, sequential upstream convergent-CBE domains. Primary pro-B cells had significantly reduced transcription of Wapl, a cohesin-unloading factor, versus levels in v-Abl pro-B lines that lack marked locus contraction or distal VH rearrangements. Correspondingly, Wapl depletion in v-Abl lines activated VH-locus contraction and orientation-specific RAG-scanning across the VH-locus. Our findings indicate that locus contraction and physiological VH-to-DJH joining both are regulated via circumvention of CBE scanning impediments.
2020-11-08 | GSE151909 | GEO
Project description:Immunoglobulin heavy chain locus (Igh) VH, D, and JH gene segments are developmentally assembled into V(D)J exons. RAG endonuclease initiates V(D)J recombination by binding a JH-recombination signal sequence (RSS) within a chromatin-based recombination center (RC) and then, in an orientation-dependent process, scans upstream D-containing chromatin presented by cohesin-mediated loop extrusion for convergent D-RSSs to initiate DJH-RC formation. In primary pro-B cells, 100s of upstream VH-associated RSSs, embedded in convergent orientation to the DJH-RC-RSS, gain proximity to the DJH-RC for VH-to-DJH joining via a mechanistically-undefined VH-locus contraction process. Here, we report that a 2.4 mega-base VH locus inversion in primary pro-B cells nearly abrogates rearrangements of normally convergent VH-RSSs and cryptic RSSs, even though locus contraction per se is maintained. Moreover, this inversion activated rearrangement of both cryptic VH-locus RSSs normally in the opposite orientation and, unexpectedly, of normally-oriented cryptic RSSs within multiple, sequential upstream convergent-CBE domains. Primary pro-B cells had significantly reduced transcription of Wapl, a cohesin-unloading factor, versus levels in v-Abl pro-B lines that lack marked locus contraction or distal VH rearrangements. Correspondingly, Wapl depletion in v-Abl lines activated VH-locus contraction and orientation-specific RAG-scanning across the VH-locus. Our findings indicate that locus contraction and physiological VH-to-DJH joining both are regulated via circumvention of CBE scanning impediments.
2020-11-08 | GSE151908 | GEO
Project description:Immunoglobulin heavy chain locus (Igh) VH, D, and JH gene segments are developmentally assembled into V(D)J exons. RAG endonuclease initiates V(D)J recombination by binding a JH-recombination signal sequence (RSS) within a chromatin-based recombination center (RC) and then, in an orientation-dependent process, scans upstream D-containing chromatin presented by cohesin-mediated loop extrusion for convergent D-RSSs to initiate DJH-RC formation. In primary pro-B cells, 100s of upstream VH-associated RSSs, embedded in convergent orientation to the DJH-RC-RSS, gain proximity to the DJH-RC for VH-to-DJH joining via a mechanistically-undefined VH-locus contraction process. Here, we report that a 2.4 mega-base VH locus inversion in primary pro-B cells nearly abrogates rearrangements of normally convergent VH-RSSs and cryptic RSSs, even though locus contraction per se is maintained. Moreover, this inversion activated rearrangement of both cryptic VH-locus RSSs normally in the opposite orientation and, unexpectedly, of normally-oriented cryptic RSSs within multiple, sequential upstream convergent-CBE domains. Primary pro-B cells had significantly reduced transcription of Wapl, a cohesin-unloading factor, versus levels in v-Abl pro-B lines that lack marked locus contraction or distal VH rearrangements. Correspondingly, Wapl depletion in v-Abl lines activated VH-locus contraction and orientation-specific RAG-scanning across the VH-locus. Our findings indicate that locus contraction and physiological VH-to-DJH joining both are regulated via circumvention of CBE scanning impediments.
2020-11-08 | GSE151907 | GEO
Project description:Immunoglobulin heavy chain locus (Igh) VH, D, and JH gene segments are developmentally assembled into V(D)J exons. RAG endonuclease initiates V(D)J recombination by binding a JH-recombination signal sequence (RSS) within a chromatin-based recombination center (RC) and then, in an orientation-dependent process, scans upstream D-containing chromatin presented by cohesin-mediated loop extrusion for convergent D-RSSs to initiate DJH-RC formation. In primary pro-B cells, 100s of upstream VH-associated RSSs, embedded in convergent orientation to the DJH-RC-RSS, gain proximity to the DJH-RC for VH-to-DJH joining via a mechanistically-undefined VH-locus contraction process. Here, we report that a 2.4 mega-base VH locus inversion in primary pro-B cells nearly abrogates rearrangements of normally convergent VH-RSSs and cryptic RSSs, even though locus contraction per se is maintained. Moreover, this inversion activated rearrangement of both cryptic VH-locus RSSs normally in the opposite orientation and, unexpectedly, of normally-oriented cryptic RSSs within multiple, sequential upstream convergent-CBE domains. Primary pro-B cells had significantly reduced transcription of Wapl, a cohesin-unloading factor, versus levels in v-Abl pro-B lines that lack marked locus contraction or distal VH rearrangements. Correspondingly, Wapl depletion in v-Abl lines activated VH-locus contraction and orientation-specific RAG-scanning across the VH-locus. Our findings indicate that locus contraction and physiological VH-to-DJH joining both are regulated via circumvention of CBE scanning impediments.
2020-11-08 | GSE151906 | GEO
Project description:RAG endonuclease initiates Igh V(D)J recombination in progenitor B cells by binding a JH-recombination signal sequence (RSS) within a recombination centre (RC) and then linearly scanning upstream chromatin, presented by loop extrusion mediated by cohesin, for convergent D-RSSs1,2. The utilization of convergently oriented RSSs and cryptic RSSs is intrinsic to long-range RAG scanning3. Scanning of RAG from the DJH-RC-RSS to upstream convergent VH-RSSs is impeded by D-proximal CTCF-binding elements (CBEs)2-5. Primary progenitor B cells undergo a mechanistically undefined contraction of the VH locus that is proposed to provide distal VHs access to the DJH-RC6-9. Here we report that an inversion of the entire 2.4-Mb VH locus in mouse primary progenitor B cells abrogates rearrangement of both VH-RSSs and normally convergent cryptic RSSs, even though locus contraction still occurs. In addition, this inversion activated both the utilization of cryptic VH-RSSs that are normally in opposite orientation and RAG scanning beyond the VH locus through several convergent CBE domains to the telomere. Together, these findings imply that broad deregulation of CBE impediments in primary progenitor B cells promotes RAG scanning of the VH locus mediated by loop extrusion. We further found that the expression of wings apart-like protein homologue (WAPL)10, a cohesin-unloading factor, was low in primary progenitor B cells compared with v-Abl-transformed progenitor B cell lines that lacked contraction and RAG scanning of the VH locus. Correspondingly, depletion of WAPL in v-Abl-transformed lines activated both processes, further implicating loop extrusion in the locus contraction mechanism.
| S-EPMC9037962 | biostudies-literature
Project description:Loop Extrusion Mediates Physiological Locus Contraction for V(D)J Recombination
| PRJNA637627 | ENA
Project description:Loop Extrusion Mediates Physiological Locus Contraction for V(D)J Recombination (3C-HTGTS)
| PRJNA637631 | ENA
Project description:Loop Extrusion Mediates Physiological Locus Contraction for V(D)J Recombination (ChIP-Seq)
| PRJNA637630 | ENA
Project description:Loop Extrusion Mediates Physiological Locus Contraction for V(D)J Recombination (GRO-Seq)
| PRJNA637624 | ENA
Project description:Loop Extrusion Mediates Physiological Locus Contraction for V(D)J Recombination (LAM-HTGTS)
| PRJNA637625 | ENA