Stop-and-go kinetics in amyloid fibrillation

Autor:	Fonslet, Jesper, Andersen, Christian Beyschau, Krishna, Sandeep, Pigolotti, Simone, Yagi, Hisashi, Goto, Yuji, Otzen, Daniel, Jensen, Mogens H., Ferkinghoff-Borg, Jesper
Rok vydání:	2009
Předmět:	Physics - Biological Physics Quantitative Biology - Subcellular Processes
Druh dokumentu:	Working Paper
Popis:	Many human diseases are associated with protein aggregation and fibrillation. We present experiments on in vitro glucagon fibrillation using total internal reflection fluorescence microscopy, providing real-time measurements of single-fibril growth. We find that amyloid fibrils grow in an intermittent fashion, with periods of growth followed by long pauses. The observed exponential distributions of stop and growth times support a Markovian model, in which fibrils shift between the two states with specific rates. Remarkably, the probability of being in the growing (stopping) state is very close to 1/4 (3/4) in all experiments, even if the rates vary considerably. This finding suggests the presence of 4 independent conformations of the fibril tip; we discuss this possibility in terms of the existing structural knowledge. Comment: 4 pages, 4 figures
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/0910.4020 Zobrazit plný text záznamu View this record from Arxiv