A proline-rich polypeptide is associated with prostatic binding protein, a major androgen-dependent protein described previously in the rat ventral prostate. This polypeptide has been purified. Its molecular weight estimated by gel filtration is about 8500, but a markedly lower value (3300) is obtained by sodium dodecyl sulfate-urea polyacrylamide gel electrophoresis. Isoelectric focusing on th...

Src homology 3 (SH3) and WW domains are known to associate with proline-rich motifs within their respective ligands. Here we demonstrate that the proposed adapter protein for Src kinases, Sam68, is a ligand whose proline-rich motifs interact with the SH3 domains of p59(fyn) and phospholipase Cgamma-1 as well as with the WW domains of FBP30 and FBP21. These proline-rich motifs, in turn, are flan...

The ability of the 3A protein of coxsackievirus B (CVB) to inhibit protein secretion was investigated for this study. Here we show that the ectopic expression of CVB 3A blocked the transport of both the glycoprotein of vesicular stomatitis virus, a membrane-bound secretory marker, and the alpha-1 protease inhibitor, a luminal secretory protein, at a step between the endoplasmic reticulum (ER) a...

In mammalian cells vasodilator-stimulated phosphoprotein (VASP) is localized to focal adhesions and areas of dynamic membrane activity where it is thought to have a role in actinfilament assembly. The proteins responsible for recruiting VASP to these sites within the cell are not known. The bacterial protein ActA binds VASP via a proline-rich motif that is very similar to a sequence in the prol...

Streptococcus mutans is considered to be the major etiologic agent of human dental caries. Attachment of S. mutans to the tooth surface is required for the development of caries and is mediated, in part, by the 185-kDa surface protein variously known as antigen I/II, PAc, and P1. Such proteins are expressed by nearly all species of oral streptococci. Characteristics of P1 include an alanine-ric...

ASPP (apoptosis-stimulating protein of p53) 2 is a pro-apoptotic protein that stimulates the p53-mediated apoptotic response. Here, we provide an overview of the structure and protein-protein interactions of ASPP2. The C-terminus of ASPP2 contains Ank (ankyrin) repeats and an SH3 domain (Src homology 3 domain). The Ank-SH3 domains mediate interactions between ASPP2 and numerous proteins involve...

Thymocyte development requires the coordinated input of signals that originate from numerous cell surface molecules. Although the majority of thymocyte signal-initiating receptors are lineage-specific, most trigger 'ubiquitous' downstream signaling pathways. T-lineage-specific receptors are coupled to these signaling pathways by lymphocyte-restricted adapter molecules. We and others recently id...

Retroviruses expressing two different receptor-binding domains linked by proline-rich spacers infect only cells expressing both retroviral receptors (Valsesia-Wittman et al., EMBO J. 6:1214-1223, 1997). Here we apply this receptor cooperation strategy to target human tumor cells by linking single-chain antibodies recognizing tumor antigens via proline-rich spacers to the 4070A murine leukemia v...