Bone marrow stromal antigen 2 (BST-2, also known as tetherin) is a recently identified interferon-inducible host restriction factor that can block the production of enveloped viruses by trapping virus particles at the cell surface. This antiviral effect is counteracted by the human immunodeficiency virus type 1 (HIV-1) accessory protein viral protein U (Vpu). Here we show that HIV-1 Vpu physica...

Several regions of the Saccharomyces cerevisiae genome are subject to position-dependent transcriptional repression mediated by a multi-component nucleosome-binding complex of silent information regulator proteins (Sir2p, Sir3p and Sir4p). These proteins are present in limiting amounts in the nucleus and are targeted to specific chromosomal regions by interaction with sequence-specific DNA-bind...

The metabolic complexity of living organisms relies on supramolecular protein structures which ensure vital processes, such as signal transduction, transcription, translation and cell wall synthesis. In eukaryotes WD40-repeat (WDR) proteins often function as molecular "hubs" mediating supramolecular interactions. WDR proteins may display a variety of interacting partners and participate in the ...

The maize (Zea mays) nucleosome remodeling factor complex component101 (nfc101) and nfc102 are putative paralogs encoding WD-repeat proteins with homology to plant and mammalian components of various chromatin modifying complexes. In this study, we generated transgenic lines with simultaneous nfc101 and nfc102 downregulation and analyzed phenotypic alterations, along with effects on RNA levels,...

The Polo-like kinase homolog in Trypanosoma brucei, TbPLK, plays essential roles in basal body segregation, flagellum attachment and cytokinesis. The level of TbPLK protein is tightly controlled, but the underlying mechanism remains elusive. Here, we report a Cullin-RING ubiquitin ligase composed of Cullin4, the DNA damage-binding protein 1 homolog TbDDB1 and a WD40-repeat protein WDR1 that con...

Transcription factors of the basic Helix-Loop-Helix (bHLH) family play a central role in cell proliferation, determination, and differentiation. In plants, the regulatory functions of bHLHs in phenylpropanoid biosynthesis have been well established with regard to other interacting-proteins; i.e., MYB and WD40 repeat proteins. On the other hand, those in alkaloid biosynthesis are greatly limited...