Comparative Proteomic Analysis of Coregulation of CIPK14 and WHIRLY1/3 Mediated Pale Yellowing of Leaves in Arabidopsis

Abstract

Pale yellowing of leaf variegation is observed in the mutant Arabidopsis lines Calcineurin B-Like-Interacting Protein Kinase14 (CIPK14) overexpression (oeCIPK14) and double-knockout WHIRLY1/WHIRLY3 (why1/3). Further, the relative distribution of WHIRLY1 (WHY1) protein between plastids and the nucleus is affected by the phosphorylation of WHY1 by CIPK14. To elucidate the coregulation of CIPK14 and WHIRLY1/WHIRLY3-mediated pale yellowing of leaves, a differential proteomic analysis was conducted between the oeCIPK14 variegated (oeCIPK14-var) line, why1/3 variegated (why1/3-var) line, and wild type (WT). More than 800 protein spots were resolved on each gel, and 67 differentially abundant proteins (DAPs) were identified by matrix-assisted laser desorption ionization-time of flight/time of flight mass spectrometry (MALDI-TOF/TOF-MS). Of these 67 proteins, 34 DAPs were in the oeCIPK14-var line and 33 DAPs were in the why1/3-var line compared to the WT. Five overlapping proteins were differentially expressed in both the oeCIPK14-var and why1/3-var lines: ATP-dependent Clp protease proteolytic subunit-related protein 3 (ClpR3), Ribulose bisphosphate carboxylase large chain (RBCL), Beta-amylase 3 (BAM3), Ribosome-recycling factor (RRF), and Ribulose bisphosphate carboxylase small chain (RBCS). Bioinformatics analysis showed that most of the DAPs are involved in photosynthesis, defense and antioxidation pathways, protein metabolism, amino acid metabolism, energy metabolism, malate biosynthesis, lipid metabolism, and transcription. Thus, in the why1/3-var and oeCIPK14-var lines, there was a decrease in the photosystem parameters, including the content of chlorophyll, the photochemical efficiency of photosystem (PS II) (Fv/Fm), and electron transport rates (ETRs), but there was an increase in non-photochemical quenching (NPQ). Both mutants showed high sensitivity to intense light. Based on the annotation of the DAPs from both why1/3-var and oeCIPK14-var lines, we conclude that the CIPK14 phosphorylation-mediated WHY1 deficiency in plastids is related to the impairment of protein metabolism, leading to chloroplast dysfunction.

Drought-Tolerance Gene Identification Using Genome Comparison and Co-Expression Network Analysis of Chromosome Substitution Lines in Rice

“…The eighteen rice genes reported here have homologs in Arabidopsis for which tagged mutants are available ( Table 2 ). Nine of them ( CPFTSY , NDH-O , SOQ1 , LHCB3 , RRF , PGRL1B , HCF244 , NAD(P)-linked oxidoreductase, and MRL1 ) were annotated to be involved in the photosynthesis process [ 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 ]. Moreover, the homolog of LOC_Os11g43600 is CPRF1, an Arabidopsis gene required for chloroplast development [ 33 ].…”

H2O2 as a Feedback Signal on Dual-Located WHIRLY1 Associates with Leaf Senescence in Arabidopsis

“…The homologous WHY3 shared 78% and 82% amino acid identity and similarity with WHY1, respectively, and was putatively dual-localized [17]. Although the real function of WHY3 was not yet clear, it was believed that WHY3 worked synergistically as a cofactor of WHY1, and was involved in stabilizing photosystem I and balancing ROS homeostasis [33,37,62]. In our experiments, the abnormal transcript levels by ectopically expressed WHY1 isoforms ( Figure 2) might affect the interactions between WHY1 and WHY3, possibly at the mRNA level or the protein level.…”

MORF9 Functions in Plastid RNA Editing with Tissue Specificity

“…The maximum photochemical efficiency of photosystem II (Fv/Fm) and the minimal initiation fluorescence yield (F0) values were measured using Imaging-PAM-Maxi (Heinz Walz GmbH, Effeltrich, Germany) as described by Guan [54]. Briefly, plants were adapted to darkness for 30 min prior to being exposed to a light intensity of 54 μmol·m −2 s −1 photosynthetically active radiation (PAR), and the kinetic curves were recorded according the instruction of the instrument.…”