A cDNA encoding a putative lectin expressed in tomato leaves was identified and analysed. The lectin consists of two homologous chitin-binding modules interconnected by a short proline-rich domain containing a single Ser[Pro]( n ) repetitive motif. Each module comprises two in-tandem-arrayed hevein domains separated by a tetrapeptide linker. Besides the chitin-binding modules and proline-rich d...

Shank proteins are a new family of scaffold proteins interacting with various membrane and cytoplasmic proteins. Shank contains multiple protein-protein interaction sites, including ankyrin repeats, an SH3 domain, a PDZ domain, a long proline-rich region and an SAM domain. The PDZ domain of Shank binds to the C-terminus of guanylate kinase-associated protein (GKAP). The PDZ domain of Shank1 fro...

A major player in membrane traffic, the large GTPase dynamin, is known in the actin dynamics field for its indirect association with the actin cytoskeleton via actinbinding proteins (ABPs) like cortactin. In this issue of The EMBO Journal, Gu et al extend this picture by revealing a direct interaction between dynamin and F-actin. They further show that oligomerized dynamin kicks off the gelsoli...

The liver has the ability to autonomously regulate growth and mass. Following partial hepatectomy, hormones, growth factors, cytokines and their coupled signal transduction pathways have been implicated in hepatocyte proliferation. To understand the mechanisms responsible for the proliferative response, we studied liver regeneration by characterization of novel genes that are activated in resid...

Members of the HMGA1 (high mobility group A1) family of architectural transcription factors, HMGA1a and HMGA1b, play important roles in many normal cellular processes and in tumorigenesis. We performed a yeast two-hybrid screen for HMGA1-interacting proteins and identified the SUMO E2 conjugase Ubc9 as one such partner. The Ubc9-interacting domain of HMGA1 is bipartite, consisting of a proline-...

Mitochondrial DNA (mtDNA) is packed into highly organized structures called mitochondrial nucleoids (mt-nucleoids). To understand the organization of mtDNA and the overall regulation of its genetic activity within the mt-nucleoids, we identified and characterized a novel mtDNA packaging protein, termed Glom (a protein inducing agglomeration of mitochondrial chromosome), from highly condensed mt...

Previous studies have suggested that salivary amylase and proline-rich protein are sorted differently when expressed in AtT-20 cells (Castle, A.M., L.E. Stahl, and J.D. Castle. 1992. J. Biol. Chem. 267:13093- 13100; Colomer, V., K. Lal, T.C. Hoops, and M.J. Rindler. 1994.EMBO (Eur. Mol. Biol. Organ.) J. 13:3711- 3719). We now show that both exocrine proteins behave similarly and enter the regul...