Protein folding and localization in the cell

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The ultimate aim of this project is to understand the principles and the pathway that newly synthesized proteins of follow in their process of acquisition of biologically functional structure and localization within the cell. More specific objective of this Cooperative Research is to stimulate information exchange and collaborations among researchers actively involved in this rapidly developing field. Following are brief summaries of the results.Goto obtained results that suggest"molten globule"structure of proteins occurs under physionlogical conditions. Yura discovered a translational regulation in the heat shock response of E. coli and identified several physiological functions of E. coli Hsps. Kagawa identified heat shok genes and proteins from a thermophilic bacterium. Yahara discovered Hsp90's role in nuclear-acting receptor-cytoskeleton interactions as well as Hsp90-casein kinase II complex. Kohno identified nuclear targeting signal carried on huma XPAC homolog. Mizushima recost … More ituted protein translocation from SecA, SecY and SecE of E. coli and dissected signal sequences for protein secretion. Ito identified SecY's domains important for calalysis and Sec complex formation, as well as a periplasmic folding factor (PpfA) acting at the disulfied bond formation. Amaya identified a yeast homolog of SRP subunit 54 and showed that it is involved in protein translocation into ER. Sakaguchi showed that charge distribution and hydrophobicity are major determinants of the orientation in protein insertion into ER membrane. Endo constructed a system to monitor conformational changes of a mitochaondrial precursor protein during translocation. Osumiidentified a cleavable N-terminal signal for targeting of 3-ketoacyl-CoA thiolase to peroxisomes. Mizunaga cloned and sequenced the yeast protein disulfide isomerase gene and showed that it is essential for viability. Yoshimori showed that some ER resident proteins can be secreted in rat exocrine pancreative cells. Hirayoshi determined the Hsp47 gene and proposed that Hsp47 is a collagen-specific chaperone. Nakano showed that the GTPase activity of SarIP in yeast is required for ER to Golgiprotein transport probably at a step subsequent to vesicle formation. Tokunaga purified and characterized yeast BiP. Less