Comprehensive Analysis of Aspergillus nidulans PKA Phosphorylome Identifies a Novel Mode of CreA Regulation

Authors

Liliane F. C. Ribeiro, University of Maryland - Baltimore County
Cynthia Chelius, University of Maryland - Baltimore County
Karthik R. Boppidi, University of Maryland - Baltimore County
Nisha S. Naik, University of Maryland - Baltimore County
Simin Hossain, University of Maryland - Baltimore County
Jessica J. J. Ramsey, University of Maryland - Baltimore County
Jyothi Kumar, University of Nebraska - Lincoln
Lucas F. Ribeiro, Johns Hopkins University
Marc Ostermeier, Johns Hopkins University
Bao Tran, University of Maryland School of Pharmacy
Young Ah Goo, University of Maryland School of Pharmacy
Leandro J. de Assis, Universidade de São Paulo
Mevlut Ulas, Maynooth University
Ozgur Bayram, Maynooth University
Gustavo H. Goldman, Universidade de São Paulo; Technical University of Munich
Stephen Lincoln, University of Connecticut,
Ranjan Srivastava, University of Connecticut,
Steven D. Harris, University of Nebraska - Lincoln
Mark R. Marten, University of Maryland - Baltimore CountyFollow

Date of this Version

2019

Citation

Ribeiro LFC, Chelius C, Boppidi KR, Naik NS, Hossain S, Ramsey JJJ, Kumar J, Ribeiro LF, Ostermeier M, Tran B, Ah Goo Y, de Assis LJ, Ulas M, Bayram O, Goldman GH, Lincoln S, Srivastava R, Harris SD, Marten MR. 2019. Comprehensive analysis of Aspergillus nidulans PKA phosphorylome identifies a novel mode of CreA regulation. mBio 10:e02825-18. https:// doi.org/10.1128/mBio.02825-18.

Comments

© 2019 Ribeiro et al. This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International license.

Abstract

In filamentous fungi, an important kinase responsible for adaptation to changes in available nutrients is cyclic AMP (cAMP)-dependent protein kinase (protein kinase A [PKA]). This kinase has been well characterized at a molecular level, but its systemic action and direct/indirect targets are generally not well understood in filamentous fungi. In this work, we used a pkaA deletion strain (ΔpkaA) to identify Aspergillus nidulans proteins for which phosphorylation is dependent (either directly or indirectly) on PKA. A combination of phosphoproteomic and transcriptomic analyses revealed both direct and indirect targets of PKA and provided a global perspective on its function. One of these targets was the transcription factor CreA, the main repressor responsible for carbon catabolite repression (CCR). In the ΔpkaA strain, we identified a previously unreported phosphosite in CreA, S319, which (based on motif analysis) appears to be a direct target of Stk22 kinase (AN5728). Upon replacement of CreA S319 with an alanine (i.e., phosphonull mutant), the dynamics of CreA import to the nucleus are affected. Collectively, this work provides a global overview of PKA function while also providing novel insight regarding significance of a specific PKA-mediated phosphorylation event.