@article{203981,
  keywords = {Animals, Drosophila, Gene Expression Regulation, Drosophila Proteins, Genes, Insect, Insulator Elements},
  author = {Olga Kyrchanova and Marat Sabirov and Vladic Mogila and Amina Kurbidaeva and Nikolay Postika and Oksana Maksimenko and Paul Schedl and Pavel Georgiev},
  title = {Complete reconstitution of bypass and blocking functions in a minimal artificial  insulator from  complex},
  abstract = { Boundaries in the  complex (BX-C) delimit autonomous regulatory domains that drive parasegment-specific expression of the  genes ,  and  The  boundary is located between the  and  domains and has two key functions: blocking cross-talk between these domains and at the same time promoting communication (boundary bypass) between  and the  promoter. Using a replacement strategy, we found that multimerized binding sites for the architectural proteins Pita, Su(Hw), and dCTCF function as conventional insulators and block cross-talk between the  and  domains; however, they lack bypass activity, and  is unable to regulate  Here we show that an \~{}200-bp sequence of dHS1 from the  boundary rescues the bypass defects of these multimerized binding sites. The dHS1 sequence is bound in embryos by a large multiprotein complex, Late Boundary Complex (LBC), that contains the zinc finger proteins CLAMP and GAF. Using deletions and mutations in critical GAGAG motifs, we show that bypass activity correlates with the efficiency of recruitment of LBC components CLAMP and GAF to the artificial boundary. These results indicate that LBC orchestrates long-distance communication between the  regulatory domain and the  gene, while the Pita, Su(Hw), and dCTCF proteins function to block local cross-talk between the neighboring regulatory domains  and . },
  year = {2019},
  journal = {Proc Natl Acad Sci U S A},
  volume = {116},
  pages = {13462-13467},
  month = {07/2019},
  issn = {1091-6490},
  doi = {10.1073/pnas.1907190116},
  language = {eng},
}