Monday, October 27, 2014

Protein folding: Turbo-charged crosslinking

David J. Craik

The efficient production of stable bioactive proteins often requires the selective formation of several disulfide crosslinks. Two recent studies have now shown that replacing cysteine with selenocysteine in the unfolded protein can autocatalyse the formation of the desired crosslinks.

DOI

Journal: Nature Chemistry

HSF-1–mediated cytoskeletal integrity determines thermotolerance and life span

Nathan A. Baird, Peter M. Douglas1, Milos S. Simic, Ana R. Grant, James J. Moresco, Suzanne C. Wolff, John R. Yates III, Gerard Manning, Andrew Dillin

The conserved heat shock transcription factor–1 (HSF-1) is essential to cellular stress resistance and life-span determination. The canonical function of HSF-1 is to regulate a network of genes encoding molecular chaperones that protect proteins from damage caused by extrinsic environmental stress or intrinsic age-related deterioration. In Caenorhabditis elegans, we engineered a modified HSF-1 strain that increased stress resistance and longevity without enhanced chaperone induction. This health assurance acted through the regulation of the calcium-binding protein PAT-10. Loss of pat-10 caused a collapse of the actin cytoskeleton, stress resistance, and life span. Furthermore, overexpression of pat-10 increased actin filament stability, thermotolerance, and longevity, indicating that in addition to chaperone regulation, HSF-1 has a prominent role in cytoskeletal integrity, ensuring cellular function during stress and aging.

DOI

Journal: Science