Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 2 de 2
Filter
Add more filters










Database
Language
Publication year range
1.
Biochim Biophys Acta ; 1481(2): 381-94, 2000 Sep 29.
Article in English | MEDLINE | ID: mdl-11018730

ABSTRACT

We used intrinsic tryptophan fluorescence to study the nucleocapsid protein from human T-cell leukemia virus-type one, HTLV-1 p15, an 85-amino-acid protein with two Trp-containing zinc-finger motifs. Fluorescence spectra suggested an interaction between the two zinc fingers and another interaction involving the C-terminal tail and the zinc fingers. Titrations with nucleic acid revealed similar, sub-micromolar affinity for poly(dT) and poly(U) in 1 mM sodium phosphate, pH 7. Double-stranded DNA bound an order of magnitude weaker, suggesting helix-destabilizing activity. Base preference of p15 was T approximately U>I approximately C approximately G>A; affinity spanned about one order of magnitude. HTLV-1 p15 bound weaker and with less variation than reported values for either human or simian immunodeficiency virus homologues. The low affinity of p15 for nonspecific nucleic acids distinguishes it from other nucleocapsid proteins, and may suggest its involvement in additional steps of the virus life cycle other than RNA packaging.


Subject(s)
Human T-lymphotropic virus 1 , Nucleic Acids/chemistry , Nucleocapsid Proteins/chemistry , Retroviridae Proteins/chemistry , Amino Acid Sequence , Hydrogen-Ion Concentration , Magnesium Chloride , Molecular Sequence Data , Nucleocapsid Proteins/isolation & purification , Phosphates , Spectrometry, Fluorescence , Tryptophan/chemistry , Zinc Fingers
2.
FEBS Lett ; 476(3): 190-3, 2000 Jul 07.
Article in English | MEDLINE | ID: mdl-10913611

ABSTRACT

Zinc finger (ZF) domains in retroviral nucleocapsid proteins usually contain one histidine per metal ion coordination complex (Cys-X(2)-Cys-X(4)-His-X(4)-Cys). Visna virus nucleocapsid protein, p8, has two additional histidines (in the second of its two ZFs) that could potentially bind metal ions. Absorption spectra of cobalt-bound ZF2 peptides were altered by Cys alkylation and mutation, but not by mutation of the extra histidines. Our results show that visna p8 ZFs involve three Cys and one His in the canonical spacing in metal ion coordination, and that the two additional histidines appear to interact with nucleic acid bases in p8-DNA complexes.


Subject(s)
DNA, Viral/metabolism , Nucleocapsid/chemistry , Nucleocapsid/metabolism , Visna-maedi virus/metabolism , Alkylation , Amino Acid Sequence , Animals , Binding Sites , Cysteine/chemistry , Histidine/chemistry , In Vitro Techniques , Kinetics , Metals/metabolism , Nucleocapsid/genetics , Sheep , Spectrometry, Fluorescence , Spectrophotometry , Visna-maedi virus/genetics , Zinc Fingers/genetics
SELECTION OF CITATIONS
SEARCH DETAIL
...