Destabilization of Nucleosomes by an Unusual DNA Conformation Adopted by Poly(dA) Small Middle Dotpoly(dT) Tracts in Vivo
Overview
Molecular Biology
Affiliations
Poly(dA) small middle dotpoly(dT) tracts are common and often found upstream of genes in eukaryotes. It has been suggested that poly(dA) small middle dotpoly(dT) promotes transcription in vivo by affecting nucleosome formation. On the other hand, in vitro studies show that poly(dA) small middle dotpoly(dT) can be easily incorporated into nucleosomes. Therefore, the roles of these tracts in nucleosome organization in vivo remain to be established. We have developed an assay system that can evaluate nucleosome formation in yeast cells, and demonstrated that relatively longer tracts such as A(15)TATA(16) and A(34) disrupt an array of positioned nucleosomes, whereas a shorter A(5)TATA(4) tract is incorporated in positioned nucleosomes of yeast minichromosomes. Thus, nucleosomes are destabilized by poly(dA) small middle dotpoly(dT) in vivo in a length-dependent manner. Furthermore, in vivo UV footprinting revealed that the longer tracts adopt an unusual DNA structure in yeast cells that corresponds to the B' conformation described in vitro. Our results support a mechanism in which a unique poly(dA) small middle dot poly(dT) conformation presets chromatin structure to which transcription factors are accessible.
Wu Z, Gong H, Zhou Z, Jiang T, Lin Z, Li J J Anim Sci Biotechnol. 2022; 13(1):8.
PMID: 35034641 PMC: 8762894. DOI: 10.1186/s40104-021-00658-z.
MNase, as a probe to study the sequence-dependent site exposures in the +1 nucleosomes of yeast.
Luo D, Kato D, Nogami J, Ohkawa Y, Kurumizaka H, Kono H Nucleic Acids Res. 2018; 46(14):7124-7137.
PMID: 29893974 PMC: 6101533. DOI: 10.1093/nar/gky502.
Fuse T, Katsumata K, Morohoshi K, Mukai Y, Ichikawa Y, Kurumizaka H PLoS One. 2017; 12(10):e0186974.
PMID: 29073207 PMC: 5658119. DOI: 10.1371/journal.pone.0186974.
Predictive Models of Recombination Rate Variation across the Drosophila melanogaster Genome.
Adrian A, Corchado J, Comeron J Genome Biol Evol. 2016; 8(8):2597-612.
PMID: 27492232 PMC: 5010912. DOI: 10.1093/gbe/evw181.
Ichikawa Y, Morohashi N, Tomita N, Mitchell A, Kurumizaka H, Shimizu M Biochem Biophys Res Commun. 2016; 476(2):57-62.
PMID: 27208777 PMC: 4902108. DOI: 10.1016/j.bbrc.2016.05.063.