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Cofactor Complexes (cofactor + complex)
Selected AbstractsFly Six-type homeodomain proteins Sine oculis and Optix partner with different cofactors during eye developmentDEVELOPMENTAL DYNAMICS, Issue 3 2005Kristy L. Kenyon Abstract Two members from the Six class of homeobox transcription factors, Sine oculis (SO) and Optix, function during development of the fly visual system. Differences in gain-of-function phenotypes and gene expression suggest that these related factors play distinct roles in the formation of the fly eye. However, the molecular nature of their functional differences remains unclear. In this study, we report the identification of two novel factors that participate in specific partnerships with Sine oculis and Optix during photoreceptor neurons formation and in eye progenitor cells. This work shows that different cofactors likely mediate unique functions of Sine oculis and Optix during the development of the fly eye and that the repeated requirement for SO function at multiple stages of eye development reflects the activity of different SO,cofactor complexes. Developmental Dynamics 234:497,504, 2005. © 2005 Wiley-Liss, Inc. [source] Protein,membrane interactions: blood clotting on nanoscale bilayersJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 2009J. H. MORRISSEY Summary., The clotting cascade requires the assembly of protease,cofactor complexes on membranes with exposed anionic phospholipids. Despite their importance, protein,membrane interactions in clotting remain relatively poorly understood. Calcium ions are known to induce anionic phospholipids to cluster, and we propose that clotting proteins assemble preferentially on such anionic lipid-rich microdomains. Until recently, there was no way to control the partitioning of clotting proteins into or out of specific membrane microdomains, so experimenters only knew the average contributions of phospholipids to blood clotting. The development of nanoscale membrane bilayers (Nanodiscs) has now allowed us to probe, with nanometer resolution, how local variations in phospholipid composition regulate the activity of key protease,cofactor complexes in blood clotting. Furthermore, exciting new progress in solid-state NMR and large-scale molecular dynamics simulations allow structural insights into interactions between proteins and membrane surfaces with atomic resolution. [source] Computational Design of Four-Helix Bundle Proteins That Bind Nonbiological CofactorsBIOTECHNOLOGY PROGRESS, Issue 1 2008Andreas Lehmann Recent work is discussed concerning the computational design of four-helix bundle proteins that form complexes with nonbiological cofactors. Given that often there are no suitable natural proteins to provide starting points in the creation of such nonbiological systems, computational design is well suited for the design and study of new protein-cofactor complexes. Recent design efforts are presented in the context of prior work on the de novo design and engineering of porphyrin-binding four-helix bundle proteins and current developments in nonlinear optical materials. Such protein-nonbiological cofactor complexes stand to enable new applications in protein science and materials research. [source] Synthesis of S -Adenosyl- L -homocysteine Capture Compounds for Selective Photoinduced Isolation of MethyltransferasesCHEMBIOCHEM, Issue 2 2010Christian Dalhoff Dr. Abstract Understanding the interplay of different cellular proteins and their substrates is of major interest in the postgenomic era. For this purpose, selective isolation and identification of proteins from complex biological samples is necessary and targeted isolation of enzyme families is a challenging task. Over the last years, methods like activity-based protein profiling (ABPP) and capture compound mass spectrometry (CCMS) have been developed to reduce the complexity of the proteome by means of protein function in contrast to standard approaches, which utilize differences in physical properties for protein separation. To isolate and identify the subproteome consisting of S -adenosyl- L -methionine (SAM or AdoMet)-dependent methyltransferases (methylome), we developed and synthesized trifunctional capture compounds containing the chemically stable cofactor product S -adenosyl- L -homocysteine (SAH or AdoHcy) as selectivity function. SAH analogues with amino linkers at the N6 or C8 positions were synthesized and attached to scaffolds containing different photocrosslinking groups for covalent protein modification and biotin for affinity isolation. The utility of these SAH capture compounds for selective photoinduced protein isolation is demonstrated for various methyltransferases (MTases) acting on DNA, RNA and proteins as well as with Escherichia coli cell lysate. In addition, they can be used to determine dissociation constants for MTase,cofactor complexes. [source] |