Mitochondrial Proteome Studies in Seeds during Germination

Abstract

Seed germination is considered to be one of the most critical phases in the plant life cycle, establishing the next generation of a plant species. It is an energy-demanding process that requires functioning mitochondria. One of the earliest events of seed germination is progressive development of structurally simple and metabolically quiescent promitochondria into fully active and cristae-containing mitochondria, known as mitochondrial biogenesis. This is a complex and tightly regulated process, which is accompanied by sequential and dynamic gene expression, protein synthesis, and post-translational modifications. The aim of this review is to give a comprehensive summary of seed mitochondrial proteome studies during germination of various plant model organisms. We describe different gel-based and gel-free proteomic approaches used to characterize mitochondrial proteomes of germinating seeds as well as challenges and limitations of these proteomic studies. Furthermore, the dynamic changes in the abundance of the mitochondrial proteomes of germinating seeds are illustrated, highlighting numerous mitochondrial proteins involved in respiration, tricarboxycylic acid (TCA) cycle, metabolism, import, and stress response as potentially important for seed germination. We then review seed mitochondrial protein carbonylation, phosphorylation, and S-nitrosylation as well as discuss the possible link between these post-translational modifications (PTMs) and the regulation of seed germination.

Thioredoxin h2 contributes to the redox regulation of mitochondrial photorespiratory metabolism

“…In good agreement with these observations, similar results were observed in both trxh2 mutant lines germinated on either MS media or under osmotic stress. Given that seed germination demands a high mitochondria activity (Czarna, Kolodziejczak, & Janska, ), it seems reasonable to hypothesize that TRX h2 may act in seed germination by regulating mitochondrial enzymes (Hägglund et al, ).…”

Phenotyping for Nitrogen Use Efficiency: Rice Genotypes Differ in N-Responsive Germination, Oxygen Consumption, Seed Urease Activities, Root Growth, Crop Duration, and Yield at Low N

“…Germination is driven primarily by hydration and energy utilization and is a oxygen consumption-intensive phase in the development of a plant ( Czarna et al, 2016 ). The role of nitrogen resources in enhancing plant productivity requires an explanation in terms of plant energetics, which remains unattempted so far.…”

Targeted Proteomics Approach Toward Understanding the Role of the Mitochondrial Protease FTSH4 in the Biogenesis of OXPHOS During Arabidopsis Seed Germination

“…In the plant life cycle, seed germination has been recognized as one of the most critical phases, in which structurally simple and metabolically quiescent organelles in dry embryos develop into mature functional forms to support the more energy-demanding processes of cell division and organogenesis of the new seedling (Paszkiewicz et al, 2017 ). Germination sensu stricto , which portrays physical and metabolic processes occurring in imbibed seeds, begins with the uptake of water by the dry seed and ends with the emergence of the radicle, being a visible symptom of the completion of germination (Rajjou et al, 2012 ; Czarna et al, 2016 ).…”

“…Although there have been several extensive studies published in the last few years, which are associated with transcriptomic changes in seed mitochondria (Narsai et al, 2011 , 2017 ; Law et al, 2012 ), there is relatively little information addressing the detailed time course of mitochondrial protein dynamics in germinating seeds. Until now, several studies using gel-based [two-dimensional (2-D) gel electrophoresis, western blotting] or gel-free proteomic approaches [mass spectrometry-based isobaric tag for relative and absolute quantitation (iTRAQ) or shotgun proteomics] have been carried out, which showed the differential abundance of various mitochondrial proteins in whole germinating seeds or isolated organelles of different plant species (e.g., A. thaliana, Oryza sativa, Pisum sativum, Zea mays ) (Logan et al, 2001 ; Howell et al, 2006 , 2007 ; Taylor et al, 2010 ; Law et al, 2012 ; Galland et al, 2014 ; Han et al, 2014 ; reviewed in Czarna et al, 2016 ). No detailed proteomics surveys have been applied so far to examine the biogenesis of the oxidative phosphorylation (OXPHOS) complexes throughout the seed germination course.…”