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Post by skyship on Mar 3, 2010 18:23:02 GMT -5
How the shift was made from natural to nano by way of Molecular Machine:======================= review article Molecular motorsManfred Schliwa & Günther Woehlke Life implies movement. Most forms of movement in the living world are powered by tiny protein machines known as molecular motors. Among the best known are motors that use sophisticated intramolecular amplification mechanisms to take nanometre steps along protein tracks in the cytoplasm. These motors transport a wide variety of cargo, power cell locomotion, drive cell division and, when combined in large ensembles, allow organisms to move. Motor defects can lead to severe diseases or may even be lethal. Basic principles of motor design and mechanism have now been derived, and an understanding of their complex cellular roles is emerging. www.nature.com/nature/journal/v422/n6933/full/nature01601.htmlskyship
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Post by skyship on Mar 3, 2010 18:28:52 GMT -5
SESSION 3 – PROTEIN FOLDING AND SECRETION IN FUNGI Reinhard Fischer Institute for Applied Life Sciences, Applied Microbiology, University of Karlsruhe, Hertzstr. 16, D-76187 Karlsruhe, Germany (reinhard.fischer@bio.uka.de) Microtubules, motors and polarized growth in Aspergillus nidulans We identified 11 kinesins in the genome of A. nidulans and took three unknown kinesins KinA, KipA and KipB for detailed studies. The conventional kinesin motor, KinA delivers cell wall components and corresponding enzymes enclosed in secretion vesicles to a vesicle supply center, called the Spitzenkorper.We found that microtubules merge at the center of growing tips and discovered that the kinesin motor KipA, related to Tea2 of Schizosaccharomyces pombe, is required for their temporal anchorage. In a ΔkipA hyphae loose directionality and grow in curves. GFP-KipA localizes to the microtubule plus end and jams behind them, suggesting that KipA is a moving motor. Using KipA as a microtubule plus end marker we determined the location of MTOCs in A. nidulans compartments close to nuclei, in the cytoplasm and at septa. For full activity of the MTOCs a novel MTOC associated protein, ApsB, is required.The third kinesin-like motor protein studied here, is KipB a member of the Kip3 family of microtubule depolymerases. kipB mutation caused a delay in anaphase and an increase of bent mitotic spindles, a decrease in depolymerization of cytoplasmic microtubules during mitosis and a failure of spindle positioning in the cell.www.aspergillus.org.uk/secure/articles/pdfs/expoitation05.pdfskyship
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Post by skyship on Mar 3, 2010 18:35:42 GMT -5
Human molecular machine from spitzenkorper AQT......................................the video and the disappearing act of the powder? because of temperature? heat, it disappears, cold become solid. High-resolution video microscopy, image analysis, and computer simulation were used to study the role of the Spitzenkörper (Spk) in apical branching of ramosa-1, a temperature-sensitive mutant of Aspergillus niger. A shift to the restrictive temperature led to a cytoplasmic contraction that destabilized the Spk, causing its disappearance.
Analysis of the role of the Spitzenkörper in fungal morphogenesis by computer simulation of apical branching in Aspergillus niger www.pnas.org/content/94/17/9096.fullskyship The spk is the particle......................
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