Ig Enhancers Increase RNA Polymerase II Stalling at Somatic Hypermutation Target Sequences

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68378050%3A_____%2F22%3A00555983" target="_blank" >RIV/68378050:_____/22:00555983 - isvavai.cz</a>

Výsledek na webu

<a href="https://journals.aai.org/jimmunol/article/208/1/143/234155/Ig-Enhancers-Increase-RNA-Polymerase-II-Stalling" target="_blank" >https://journals.aai.org/jimmunol/article/208/1/143/234155/Ig-Enhancers-Increase-RNA-Polymerase-II-Stalling</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.4049/jimmunol.2100923" target="_blank" >10.4049/jimmunol.2100923</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Ig Enhancers Increase RNA Polymerase II Stalling at Somatic Hypermutation Target Sequences

Popis výsledku v původním jazyce

Somatic hypermutation (SHM) drives the genetic diversity of Ig genes in activated B cells and supports the generation of Abs with increased affinity for Ag. SHM is targeted to Ig genes by their enhancers (diversification activators [DIVACs]), but how the enhancers mediate this activity is unknown. We show using chicken DT40 B cells that highly active DIVACs increase the phosphorylation of RNA polymerase II (Pol II) and Pol II occupancy in the mutating gene with little or no accompanying increase in elongation competent Pol II or production of full-length transcripts, indicating accumulation of stalled Pol II. DIVAC has similar effect also in human Ramos Burkitt lymphoma cells. The DIVAC-induced stalling is weakly associated with an increase in the detection of ssDNA bubbles in the mutating target gene. We did not find evidence for antisense transcription, or that DIVAC functions by altering levels of H3K27ac or the histone variant H3.3 in the mutating gene. These findings argue for a connection between Pol II stalling and cis acting targeting elements in the context of SHM and thus define a mechanistic basis for locus-specific targeting of SHM in the genome. Our results suggest that DIVAC elements render the target gene a suitable platform for AID-mediated mutation without a requirement for increasing transcriptional output.

Název v anglickém jazyce

Ig Enhancers Increase RNA Polymerase II Stalling at Somatic Hypermutation Target Sequences

Popis výsledku anglicky

Somatic hypermutation (SHM) drives the genetic diversity of Ig genes in activated B cells and supports the generation of Abs with increased affinity for Ag. SHM is targeted to Ig genes by their enhancers (diversification activators [DIVACs]), but how the enhancers mediate this activity is unknown. We show using chicken DT40 B cells that highly active DIVACs increase the phosphorylation of RNA polymerase II (Pol II) and Pol II occupancy in the mutating gene with little or no accompanying increase in elongation competent Pol II or production of full-length transcripts, indicating accumulation of stalled Pol II. DIVAC has similar effect also in human Ramos Burkitt lymphoma cells. The DIVAC-induced stalling is weakly associated with an increase in the detection of ssDNA bubbles in the mutating target gene. We did not find evidence for antisense transcription, or that DIVAC functions by altering levels of H3K27ac or the histone variant H3.3 in the mutating gene. These findings argue for a connection between Pol II stalling and cis acting targeting elements in the context of SHM and thus define a mechanistic basis for locus-specific targeting of SHM in the genome. Our results suggest that DIVAC elements render the target gene a suitable platform for AID-mediated mutation without a requirement for increasing transcriptional output.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

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OECD FORD obor

30102 - Immunology

Projekt

<a href="/cs/project/GA15-24776S" target="_blank" >GA15-24776S: Chybné cílení somatických hypermutací a jeho vliv na nestabilitu genomu B lymfocytů</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2022

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Immunology

ISSN

0022-1767

e-ISSN

1550-6606

Svazek periodika

208

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

12

Strana od-do

143-154

Kód UT WoS článku

000735220200015

EID výsledku v databázi Scopus

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