Crystallographic studies of the structured core domain of Knr4 from Saccharomyces cerevisiae.

The potentially structured core domain of the intrinsically disordered protein Knr4 from Saccharomyces cerevisiae, comprising residues 80-340, was expressed in Escherichia coli and crystallized using the hanging-drop vapour-diffusion method. Selenomethionine-containing (SeMet) protein was also purified and crystallized. Crystals of both proteins belonged to space group P6522, with unit-cell parameters a = b = 112.

Finding undetected protein associations in cell signaling by belief propagation.

External information propagates in the cell mainly through signaling cascades and transcriptional activation, allowing it to react to a wide spectrum of environmental changes. High-throughput experiments identify numerous molecular components of such cascades that may, however, interact through unknown partners. Some of them may be detected using data coming from the integration of a protein-protein interaction network and mRNA expression profiles.

Knr4 N-terminal domain controls its localization and function during sexual differentiation and vegetative growth.

The Saccharomyces cerevisiae protein Knr4 is composed of a globular central core flanked by two natively disordered regions. Although the central part of the protein holds most of its biological function, the N-terminal domain (amino acids 1-80) is essential in the absence of a functional CWI pathway. We show that this specific protein domain is required for the proper cellular localization of Knr4 at sites of polarized growth during vegetative growth and sexual differentiation (bud tip and 'shmoo' tip).

Functional dissection of an intrinsically disordered protein: understanding the roles of different domains of Knr4 protein in protein-protein interactions.

Knr4, recently characterized as an intrinsically disordered Saccharomyces cerevisiae protein, participates in cell wall formation and cell cycle regulation. It is constituted of a functional central globular core flanked by a poorly structured N-terminal and large natively unfolded C-terminal domains. Up to now, about 30 different proteins have been reported to physically interact with Knr4.

Contribution to the elucidation of the structure of the bacterial flagellum nano-motor through AFM imaging of the M-Ring.

The flagellar nano-motor of bacteria is one of the most interesting and amazing natural nano-machine. Despite its discovery 30 years ago, some details of its structure and mechanisms are not yet elucidated. Several studies have revealed some important aspects of its structure and numerous data are available today; however, the inner mechanisms of the nano-motor have not been yet resolved, partially due to the lack of information about the 3D assembly, shape and interactions of the different parts in experimental environment as close as possible as the native cellular conditions.