Neuronal tau induces DNA conformational changes observed by atomic force microscopy.
Neuronal tau associates with chromosome scaffold and localizes in the nuclear and the nucleolar organization regions in neuronal and some non-neuronal cells. Observing the interaction of neuronal tau with DNA under AFM shows that tau binds to DNA as a monomer, and tau-DNA complex forms a beads-on-a-string structure when the mass ratio is 1:10 (molar ratio of tau/DNA approximately 1:700 bp). A beads-on-a-coil structure, in which tau is as polymers, will appear when the mass ratio is up to 1:5 (molar ratio of tau/DNA approximately 1:350 bp). The present observation that neuronal tau bends the DNA double strands indicates that the appearance of the tau-DNA complex is dependent upon the mass (or molar) ratio of tau and DNA.
Qu
Mei-hua
MH
Laboratory of Visual Information Processing, Center for Brain and Cognitive Sciences, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Chaoyang District, Beijing 100101.
Li
Hui
H
Tian
Rui
R
Nie
Chun-lai
CL
Liu
Ying
Y
Han
Bao-shan
BS
He
Rong-qiao
RQ
D004247:DNA / Q000737:chemistry / Q000187:drug effects* / Q000648:ultrastructure; D006801:Humans; D018625:Microscopy, Atomic Force; D009690:Nucleic Acid Conformation; D011485:Protein Binding; D016875:tau Proteins / Q000737:chemistry / Q000494:pharmacology*
D016875:tau Proteins; D004247:DNA