Signal Peptide of Human Serum Albumin (residues 1-18) Forms Amyloid-like Aggregates

Abstract

Signal peptides (SPs) are essential tools in sorting or translocating the synthesized proteins. However, except few examples, their studies in isolation are quite limited. Here we asked a question of the aggregation propensity of signal peptide (residues 1-18) of Human Serum Albumin (HSA). Molecular dynamic simulations were used to acquire observations into the mechanism through which signal peptides of HSA self-aggregated in physiological conditions. Further, we confirmed our results by combining dye-based assays, atomic force microscopy, and transmission electron microscopy techniques. It was noted that the signal peptide of HSA (region 1-18) forms typical amyloid-like fibrils. Graphical O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=170 SRC="FIGDIR/small/563726v1_ufig1.gif" ALT="Figure 1"> View larger version (32K): org.highwire.dtl.DTLVardef@404ffaorg.highwire.dtl.DTLVardef@42e4caorg.highwire.dtl.DTLVardef@1ba942aorg.highwire.dtl.DTLVardef@556bee_HPS_FORMAT_FIGEXP M_FIG C_FIG