Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:3.1.31.1 (
micrococcal nuclease
)
2,818
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Eukaryotic DNA is packaged into chromatin, which regulates genome activities such as telomere maintenance. This study focuses on the interactions of a myb/SANT DNA-binding domain from the telomere-binding protein,
TRF2
, with reconstituted telomeric nucleosomal array fibers. Biophysical characteristics of the factor-bound nucleosomal arrays were determined by analytical agarose gel electrophoresis (AAGE) and single molecules were visualized by atomic force microscopy (AFM). The
TRF2
DNA-binding domain (
TRF2
DBD) neutralized more negative charge on the surface of nucleosomal arrays than histone-free DNA. Binding of
TRF2
DBD at lower concentrations increased the radius and conformational flexibility, suggesting a distortion of the fiber structure. Additional loading of
TRF2
DBD onto the nucleosomal arrays reduced the flexibility and strongly blocked access of
micrococcal nuclease
as contour lengths shortened, consistent with formation of a unique, more compact higher-order structure. Mirroring the structural results,
TRF2
DBD stimulated a strand invasion-like reaction, associated with telomeric t-loops, at lower concentrations while inhibiting the reaction at higher concentrations. Full-length
TRF2
was even more effective at stimulating this reaction. The
TRF2
DBD had less effect on histone-free DNA structure and did not stimulate the t-loop reaction with this substrate, highlighting the influence of chromatin structure on the activities of DNA-binding proteins.
...
PMID:The Myb/SANT domain of the telomere-binding protein TRF2 alters chromatin structure. 1953 42
