A conserved phosphoprotein that specifically binds nuclear localization sequences is involved in nuclear import.
J Cell Biol
; 117(3): 473-82, 1992 May.
Article
en En
| MEDLINE
| ID: mdl-1572892
We have purified proteins of 70 kD from Drosophila, HeLa cells, and Z. mays that specifically bind nuclear localization sequences (NLSs). These proteins are recognized by antibodies raised against a previously identified NLS-binding protein (NBP) from the yeast S. cerevisiae. All NBPs are associated with nuclei and also present in the cytosol. NBPs are phosphorylated and phosphatase treatment abolished NLS binding. The requirement for NBPs in nuclear protein uptake is demonstrated in semipermeabilized Drosophila melanogaster tissue culture cells. Proper import of a fluorescent protein containing the large T antigen NLS requires cytosol and ATP. In the absence of cytosol and/or ATP, NLS-containing proteins are bound to cytosolic structures and the nuclear envelope. Addition of cytosol and ATP results in movement of this bound intermediate into the nucleus. Anti-NBP antibodies specifically inhibited the binding part of this import reaction. These results indicate that a phosphoprotein common to several eukaryotes acts as a receptor that recognizes NLSs before their uptake into the nucleus.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Fosfoproteínas
/
Señales de Clasificación de Proteína
/
Proteínas Nucleares
/
Núcleo Celular
/
Citoplasma
Límite:
Animals
/
Humans
Idioma:
En
Revista:
J Cell Biol
Año:
1992
Tipo del documento:
Article
Pais de publicación:
Estados Unidos