Expression of Protein Complexes and Individual Proteins Upon Transition of Etioplasts to Chloroplasts in Pea (Pisum sativum)

Abstract

The protein complexes of pea (Pisum sativum L.) etioplasts, etio-chloroplasts and chloroplasts were examined using 2D Blue Native/SDS-PAGE. The most prominent protein complexes in etioplasts were the ATPase and the Clp and FtsH protease complexes which probably have a crucial role in the biogenesis of etioplasts and chloroplasts. Also the cytochrome b(6)f (Cyt b(6)f) complex was assembled in the etioplast membrane, as well as Rubisco, at least partially, in the stroma. These complexes are composed of proteins encoded by both the plastid and nuclear genomes, indicating that a functional cross-talk exists between pea etioplasts and the nucleus. In contrast, the proteins and protein complexes that bind chlorophyll, with the PetD subunit and the entire Cyt b(6)f complex as an exception, did not accumulate in etioplasts. Nevertheless, some PSII core components such as PsbE and the luminal oxygen-evolvong complex (OEC) proteins PsbO and PsbP accumulated efficiently in etioplasts. After 6 h de-etiolation, a complete PSII core complex appeared with 40% of the maximal photochemical efficiency, but a fully functional PSII was recorded only after 24 h illumination. Similarly, the core complex of PSI was assembled after 6 h illumination, whereas the PSI-light-harvesting complex I was stably assembled only in chloroplasts illuminated for 24 h. Moreover, a battery of proteins responsible for defense against oxidative stress accumulated particularly in etioplasts, including the stromal and thylakoidal forms of ascorbate peroxidase, glutathione reductase and PsbS.

The Chloroplast NAD(P)H Dehydrogenase Complex Interacts with Photosystem I in Arabidopsis

“…Development-Previous reports showed that the NDH complex is already present in etioplasts (27,39). However, the assembly of PSI is light-dependent, and the PSI-LHCI complex is stably assembled only in the chloroplast, which develops at least 24 h after exposure to light (39).…”

A Comprehensive Analysis of Chromoplast Differentiation Reveals Complex Protein Changes Associated with Plastoglobule Biogenesis and Remodeling of Protein Systems in Sweet Orange Flesh

“…In Arabidopsis, knocking out most members of the Clp protease family results in reduced plant growth with pale-green or variegated leaf phenotype, indicating the crucial role of the Clp complex in chloroplast development (Meinke et al, 2008;Liu et al, 2010;Olinares et al, 2011). Previous studies have revealed that the Clp complex, one of the prominent complexes, increases in abundance during the transition from proplastids or etioplasts into chloroplasts (Kanervo et al, 2008;Majeran et al, 2010). Our study shows that the proteins involved in protein degradation are among the proteins of the highest abundance during the amyloplastto-chromoplast transition, while an apparent increasing tendency in protein abundance of the Clp complex suggests that the machinery of protein degradation or processing during chromoplast differentiation might have distinct modulating functions that are conserved during the biogenesis of both chloroplasts and chromoplasts.…”

“…The majority of chromoplast-related studies are concerned with the functions of these organelles in various crops, such as pepper, tomato, watermelon (Citrulis lanatus), carrot, cauliflower (Brassica oleracea), and papaya (Siddique et al, 2006;Wang et al, 2013). However, only a few of such studies addressed the mechanisms underlying plastid differentiation, such as the transition from proplastid to chloroplast in maize (Zea mays; Majeran et al, 2010), from etioplast to chloroplast in pea (Pisum sativum; Kanervo et al, 2008) and rice (Oryza sativa; Kleffmann et al, 2007), and from chloroplast to chromoplast in tomato (Barsan et al, 2012). In tomato, chromoplastogenesis appears to be associated with major metabolic shifts, including a strong decrease in abundance of the proteins involved in light reaction and an increase in terpenoid biosynthesis and stress-response proteins (Barsan et al, 2012).…”

Gain and Loss of Photosynthetic Membranes during Plastid Differentiation in the Shoot Apex of Arabidopsis

“…During this process, etioplasts, which contain prolamellar bodies (PLBs) and perforated lamellae called prothylakoids, are converted into functional chloroplasts that possess fully mature thylakoid networks. PLBs contain many of the building blocks of the thylakoid membrane, including MGDG, the chlorophyll precursor protochlorophyllide, enzymes involved in chlorophyll and carotenoid biosynthesis, and proteins involved in photosynthetic light reactions (Lonosky et al, 2004;Kleffmann et al, 2007;Blomqvist et al, 2008;Kanervo et al, 2008). This transition is therefore quite different from the one occurring at the shoot apex (from the L2 to the leaf primordia), both in its starting point (PLBs and prothylakoidcontaining etioplasts versus thylakoid-less proplastids) and its end point (fully mature versus partially mature networks).…”