Malte Brettel

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We have investigated the functional role of the non-helical end domains of vimentin on its assembly properties using truncated Xenopus and human recombinant proteins. Removal of the amino-terminal "head" domain yielded a molecule that did not assemble into 10 nm filaments but remained in a soluble oligomeric particle form with a sedimentation coefficient(More)
We have determined the mass-per-length (MPL) composition of distinct early assembly products of recombinant intermediate filament (IF) proteins from the four cytoplasmic sequence homology classes, and compared these values with those of the corresponding mature filaments. After two seconds under standard assembly conditions (i.e. 25 mM Tris-HCl (pH 7.5), 50(More)
In assembly assays of intermediate filaments (IFs) from vimentin of the amphibian species Xenopus laevis we have observed the formation of so far unknown structures at temperatures above 28 degrees C. Upon assembly in vitro at temperatures above 34 degrees C massive aggregates, partly with a protofilamentous substructure, were found and their formation(More)
Plakophilin 1 and 2 (PKP1, PKP2) are members of the arm-repeat protein family. They are both constitutively expressed in most vertebrate cells, in two splice forms named a and b, and display a remarkable dual location: they occur in the nuclei of cells and, in epithelial cells, at the plasma membrane within the desmosomal plaques. We have shown by solid(More)
We have isolated from a rainbow trout (Oncorhynchus mykiss) spleen cDNA library a clone coding for vimentin. The deduced amino acid sequence reveals a high degree of identity with vimentin from carp (81%), frog (71%), chick and human (73% each). Large stretches in the central alpha-helical rod are identical within all four classes of vertebrates, but in 17(More)
Nearly all intermediate filament proteins exhibit a highly conserved amino acid motif (YRKLLEGEE) at the C-terminal end of their central alpha-helical rod domain. We have analyzed its contribution to the various stages of assembly by using truncated forms of Xenopus vimentin and mouse desmin, VimIAT and DesIAT, which terminate exactly before this motif, by(More)
Field Editor: D. Shepherd Innovative products are widely recognized as an important source of competitive advantage. However, many companies have difficulties finding efficient and successful approaches to different types of R&D projects, particularly those that involve a high level of innovativeness. Therefore, the present study moves effectuation theory(More)
Absorptive capacity (ACAP) is a firm’s ability to innovate by identifying, assimilating, and exploiting knowledge available in its environment. ACAP has been widely researched, but this research has not sufficiently analyzed the influence of ACAP on an interfirm level, especially regarding the multidimensional character of this construct. The present study(More)
Online advertising has shortand long-term effects. Little is known, however, about which online advertising channel works best to address particular customer groups when shortand long-term effects, are taken into account. We look at the sales effect of search engine marketing (SEM), banner advertising, price comparison advertising (PCA) and coupon/loyalty(More)
a r t i c l e i n f o Keywords: Social capital Organizational learning New product development Interaction effects This paper examines the effect of the elements of top management's social capital on exploratory and exploitative learning and on the outcomes of new product development (NPD), as well as the interaction effects of these elements with external(More)