We identified that whirlin is localized to chromosome 9q32-33, and is up-regulated in colorectal cancer tissues by using oligonucleotide array techniques and the Sosui system (http://www.tuat.ac.jp/~mitaku/sosui/). The deduced 920-amino acid protein encoded by the whirlin gene contains three PDZ domains and a proline-rich region that separates PDZ2 from PDZ3, which is located at the C terminus....

Histidine-proline-rich glycoprotein (HPRG) is an abundant multidomain plasma protein evolutionarily related to high-molecular-weight kininogen. The cleaved form of high-molecular-weight kininogen has recently been demonstrated to exhibit antiangiogenic activities in vitro (J. C. Zhang et al., FASEB J., 14: 2589-2600, 2000), mediated primarily through domain 5. HPRG contains a histidine-proline-...

The multifunctional protein profilin is one of the most abundant proteins in the cytoplasm and is thought to regulate actin assembly and the phosphoinositide signaling pathway. Profilin binds to several different ligands including actin, poly-L-proline, and the head groups of polyphosphoinositides. Knowledge of profilin/ligand interactions is important for understanding the physiology of profil...

ALIX recruits ESCRT-III CHMP4 and is involved in membrane remodeling during endosomal receptor sorting, budding of some enveloped viruses, and cytokinesis. We show that ALIX dimerizes via the middle domain (ALIX(-V)) in solution. Structural modeling based on small angle X-ray scattering (SAXS) data reveals an elongated crescent-shaped conformation for dimeric ALIX lacking the proline-rich domai...

To identify a growth-promoting activity related to retinoblastoma-interacting-zinc-finger (RIZ) protein, differential protein expression of MCF-7 cell lines expressing the zinc-finger or the proline-rich domain of RIZ protein was analyzed by a robust bottom-up mass-spectrometry proteomic approach. Spots corresponding to qualitative and quantitative differences in protein expression have been se...

A panel of murine monoclonal antibodies (MAbs) to the human immunodeficiency virus type 1 trans-activator tat protein were characterized. The anti-tat MAbs were mapped to the different domains of the tat protein by Western blot (immunoblot) and Pepscan analyses. One-half of the MAbs tested mapped to the amino-terminal proline-rich region, and one-third of the MAbs tested mapped to the lysine-ar...

The kinase activity of c-Abl is known to be tightly regulated. Mechanisms of c-Abl kinase regulation can be classified as intramolecular or intermolecular interactions. Crystallization of the amino (N)-terminal region of c-Abl has revealed that intramolecular folding of the N terminus onto the kinase domain represses intrinsic kinase activity. With regard to intermolecular interactions, recent ...

We have shown previously that protein tyrosine phosphatase (PTP) 1B interacts with insulin receptor and negatively regulates insulin signalling by an N-terminal binding domain [Dadke, Kusari and Chernoff (2000) J. Biol. Chem. 275, 23642-23647] and it also negatively regulates integrin signalling through a proline-rich region present in the C-terminus [Liu, Hill and Chernoff (1996) J. Biol. Chem...

Nine neurodegenerative diseases, such as Huntington, are caused by a polyglutamine (poly(Q)) expansion in otherwise unrelated proteins. Although poly(Q) expansion causes aggregation of the affected proteins, the protein context might determine the selective neuronal vulnerability found in each disease. Here we have report that, although expression of Huntingtin derivatives with a pathological p...

Aromatic rings exhibit defined interactions via the unique aromatic π face. Aromatic amino acids interact favorably with proline residues via both the hydrophobic effect and aromatic-proline interactions, C-H/π interactions between the aromatic π face and proline ring C-H bonds. The canonical aromatic amino acids Trp, Tyr, and Phe strongly disfavor a polyproline helix (PPII) when they are prese...