Cookies on this website
We use cookies to ensure that we give you the best experience on our website. If you click 'Continue' we'll assume that you are happy to receive all cookies and you won't see this message again. Click 'Find out more' for information on how to change your cookie settings.

© 2019 The Author(s) Alternative translation is an important mechanism of post-transcriptional gene regulation leading to the expression of different protein isoforms originating from the same mRNA. Here, we describe an abundant long isoform of the stress/p38MAPK-activated protein kinase MK2. This isoform is constitutively translated from an alternative CUG translation initiation start site located in the 5′ UTR of its mRNA. The RNA helicase eIF4A1 is needed to ensure translation of the long and the known short isoforms of MK2, of which the molecular properties were determined. Only the short isoform phosphorylated Hsp27 in vivo, supported migration and stress-induced immediate early gene (IEG) expression. Interaction profiling revealed short-isoform-specific binding partners that were associated with migration. In contrast, the long isoform contains at least one additional phosphorylatable serine in its unique N terminus. In sum, our data reveal a longer isoform of MK2 with distinct physiological properties. In the present study, Trulley et al. identify a N-terminal extended long isoform of the stress-activated protein kinase MK2 that constitutively arises from alternative translation initiation within the known MK2 mRNA. The long isoform has unique and shared molecular properties, compared to the canonical short isoform.

Original publication

DOI

10.1016/j.celrep.2019.05.024

Type

Journal article

Journal

Cell Reports

Publication Date

04/06/2019

Volume

27

Pages

2859 - 2870.e6