From Wikipedia,
the free encyclopedia.
A nuclear localizing signal
(NLS) is an amino acid
sequence which acts like a 'tag'
on the exposed surface of a
protein. This sequence is used
to confine the protein to the cell
nucleus and to direct a newly
synthesized protein into the
nucleus via its recognition by
cytosolic
nuclear transport receptors.
Typically, this signal consists of
a few short sequences of
positively charged lysines or
arginines. Different nuclear
localized proteins may share the
same NLS.
Genetically the NLS results
from transcription of a nuclear
localizing sequence. Cellular
processes and protein function may
be studied by adding a known NLS
sequence to a gene, confining the
chimeric protein product to
the
nucleus. An NLS is the
opposite of a
nuclear export signal, which
confines proteins to the
cytosolic face of the
nuclear membrane.
