background: the canonical wnt signal transduction (or the wnt/β-catenin pathway) plays a crucial role in the development of animals and in carcinogenesis. beta-catenin is the central component of this signaling pathway. the activation of wnt/β-catenin signaling results in the cytoplasmic and nuclear accumulation of β-catenin. in the nucleus, β-catenin interacts with the tcf/lef transcription fa...

Of the >40 alternative and aberrant splice variants of MDM2 that have been described to date, the majority has lost both the well-characterized nuclear localization signal (NLS1) and the nuclear export signal (NES) sequence. Because cellular localization of proteins provides insight regarding their potential function, we determined the localization of three different MDM2 splice variants. The s...

The recently determined crystal structure of a nuclear localization sequence receptor has revealed an exquisitely specific interaction between ligand and receptor, and explains how simple and complex nuclear localization signals can both be recognized specifically by the same molecule.

The nuclear export of intron-containing HIV-1 RNA is critically dependent on the activity of Rev, a virally encoded sequence-specific RNA-binding protein. Rev shuttles between the nucleus and the cytoplasm and harbors both a nuclear localization signal and a nuclear export signal. These essential peptide motifs have now been shown to function by accessing cellular signal-mediated pathways for n...

A variety of nuclear localization signals (NLSs) are experimentally known although only one motif was available for database searches through PROSITE. We initially collected a set of 91 experimentally verified NLSs from the literature. Through iterated 'in silico mutagenesis' we then extended the set to 214 potential NLSs. This final set matched in 43% of all known nuclear proteins and in no kn...

Following the original approach introduced by T. Cazenave and P.L. Lions in [4] we prove the existence and the orbital stability of standing waves for the following class of NLS: (0.1) i∂tu + ∆u − V (x)u + Q(x)u|u| p−2 = 0, (t, x) ∈ R × R n , 2 < p < 2 + 4 n and (0.2) i∂tu − ∆ 2 u − V (x)u + Q(x)u|u| p−2 = 0, (t, x) ∈ R × R n , 2 < p < 2 + 8 n under suitable assumptions on the potentials V (x) ...

MAPK cascades can be negatively regulated by members of the MAPK phosphatase (MKP) family. However, how MKP activity is regulated is not well characterized. MKP-7, a JNK-specific phosphatase, possesses a unique COOH-terminal stretch (CTS) in addition to domains conserved among MKP family members. The CTS contains several motifs such as a nuclear localization signal, a nuclear export signal, PES...

Many cargoes destined for nuclear import carry nuclear localization signals that are recognized by karyopherins (Kaps). We present methods to quantitate import rates and measure Kap and cargo concentrations in single yeast cells in vivo, providing new insights into import kinetics. By systematically manipulating the amounts, types, and affinities of Kaps and cargos, we show that import rates in...