Role of the ribosome‐associated protein PY in the cold‐shock response of Escherichia coli

MicrobiologyOpen

Fabio Di Pietro¹  Anna Brandi¹  Nadire Dzeladini¹  Attilio Fabbretti¹  Thomas Carzaniga²  Lolita Piersimoni³  Cynthia L. Pon¹ 

[1] Laboratory of Molecular Biology and Biotechnology, School of Biosciences and Biotechnology, University of Camerino, Camerino (MC), Italy;Dipartimento di Bioscienze, Università degli Studi di Milano, Milan, Italy;Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, Michigan

关键词: Cold shock;    protein PY;    translation initiation;    translation regulation;   

DOI  :  10.1002/mbo3.68

来源: Wiley

【 摘 要 】

Abstract

Protein Y (PY) is an Escherichia coli cold-shock protein which has been proposed to be responsible for the repression of bulk protein synthesis during cold adaptation. Here, we present in vivo and in vitro data which clarify the role of PY and its mechanism of action. Deletion of yfiA, the gene encoding protein PY, demonstrates that this protein is dispensable for cold adaptation and is not responsible for the shutdown of bulk protein synthesis at the onset of the stress, although it is able to partially inhibit translation. In vitro assays reveal that the extent of PY inhibition changes with different mRNAs and that this inhibition is related to the capacity of PY of binding 30S subunits with a fairly strong association constant, thus stimulating the formation of 70S monomers. Furthermore, our data provide evidence that PY competes with the other ribosomal ligands for the binding to the 30S subunits. Overall these results suggest an alternative model to explain PY function during cold shock and to reconcile the inhibition caused by PY with the active translation observed for some mRNAs during cold shock.

【 授权许可】

CC BY   
© 2013 The Authors. MicrobiologyOpen published by Blackwell Publishing Ltd.

Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.