Details zur Publikation

Kategorie Textpublikation
Referenztyp Zeitschriften
DOI 10.1080/15476286.2022.2082147
Lizenz creative commons licence
Titel (primär) The sRNA NsiR4 fine-tunes arginine synthesis in the cyanobacterium Synechocystis sp. PCC 6803 by post-transcriptional regulation of PirA
Autor Bolay, P.; Hemm, L.; Florencio, F.J.; Hess, W.R.; Muro-Pastor, M.I.; Klähn, S.
Quelle RNA Biology
Erscheinungsjahr 2022
Department SOMA
Band/Volume 19
Heft 1
Seite von 811
Seite bis 818
Sprache englisch
Topic T7 Bioeconomy
Supplements https://ndownloader.figstatic.com/files/35793894
Keywords Cyanobacteria; nitrogen assimilation; arginine metabolism; RNA regulator; sRNA; posttranscriptional regulation
Abstract As the only oxygenic phototrophs among prokaryotes, cyanobacteria employ intricate mechanisms to regulate common metabolic pathways. These mechanisms include small protein inhibitors exerting their function by protein–protein interaction with key metabolic enzymes and regulatory small RNAs (sRNAs). Here we show that the sRNA NsiR4, which is highly expressed under nitrogen limiting conditions, interacts with the mRNA of the recently described small protein PirA in the model strain Synechocystis sp. PCC 6803. In particular, NsiR4 targets the pirA 5ʹUTR close to the ribosome binding site. Heterologous reporter assays confirmed that this interaction interferes with pirA translation. PirA negatively impacts arginine synthesis under ammonium excess by competing with the central carbon/nitrogen regulator PII that binds to and thereby activates the key enzyme of arginine synthesis, N-acetyl-L-glutamate-kinase (NAGK). Consistently, ectopic nsiR4 expression in Synechocystis resulted in lowered PirA accumulation in response to ammonium upshifts, which also affected intracellular arginine pools. As NsiR4 and PirA are inversely regulated by the global nitrogen transcriptional regulator NtcA, this regulatory axis enables fine tuning of arginine synthesis and conveys additional metabolic flexibility under highly fluctuating nitrogen regimes. Pairs of small protein inhibitors and of sRNAs that control the abundance of these enzyme effectors at the post-transcriptional level appear as fundamental building blocks in the regulation of primary metabolism in cyanobacteria.
dauerhafte UFZ-Verlinkung https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=26248
Bolay, P., Hemm, L., Florencio, F.J., Hess, W.R., Muro-Pastor, M.I., Klähn, S. (2022):
The sRNA NsiR4 fine-tunes arginine synthesis in the cyanobacterium Synechocystis sp. PCC 6803 by post-transcriptional regulation of PirA
RNA Biol. 19 (1), 811 - 818 10.1080/15476286.2022.2082147