Plastid Proteomics in Higher Plants: Current State and Future Goals

Proteomic Analysis of Chloroplast-to-Chromoplast Transition in Tomato Reveals Metabolic Shifts Coupled with Disrupted Thylakoid Biogenesis Machinery and Elevated Energy-Production Components

“…In addition, it provides an in-depth description of the changes occurring in the plastidial proteome during chloroplast-to-chromopast differentiation. The mechanisms governing the differentiation of plastids such as the conversion of proplastids to chloroplasts or chloroplasts to chromoplasts have received little attention and are barely mentioned in recent reviews on plastid proteomics (Armbruster et al, 2011;van Wijk and Baginsky, 2011). The pattern of changes in protein abundance reported here is in agreement with proteomic data generated in whole fruit by others (Rocco et al, 2006;Faurobert et al, 2007).…”

“…Most of the data available were related to chloroplasts (Armbruster et al, 2011;van Wijk and Baginsky, 2011), although some information was also available for nonphotosynthetic plastid structures such as amyloplasts (Andon et al, 2002;Balmer et al, 2006), etioplasts (von Zychlinski et al, 2005, proplastids (Baginsky et al, 2004), and embryoplasts (Demartini et al, 2011). The present inventory also provides information that complements previous articles published on the chromoplast proteome (bell pepper: Siddique et al, 2006;tomato: Barsan et al, 2010;and sweet orange: Zeng et al, 2011).…”

“…In the recent years high-throughput technologies have provided novel and extensive information on the plastid proteome of higher plants with strong emphasis on the chloroplast (for review, see van Wijk and Baginsky, 2011). Less information is available on the chromoplast proteome to the studies focusing on pepper (Capsicum annuum; Siddique et al, 2006), tomato , and sweet orange (Citrus sinensis; Zeng et al, 2011).…”

Plastid-bearing sea slugs fix CO2in the light but do not require photosynthesis to survive

“…The predicted proteome of Arabidopsis plastids ranges from 1000 to approximately 3500 proteins [11], but plastid genomes only encode for 60 (higher plants) to 200 (red algae) protein-coding genes in the organelle's DNA [12]. The remaining plastid proteins (more than 90%) are encoded in the nucleus, synthesized as precursor proteins on cytosolic ribosomes and imported from the cytosol through the plastid-specific protein translocon machinery (reviewed in [13][14][15]).…”

“…However, Pierce et al [25] reported that among the 100 million E. chlorotica transcripts that they sequenced, about 100 reads might indicate LGT in E. chlorotica, although only one pointed to an essential function in photosynthesis (a light-harvesting complex protein). But photosynthesis requires the expression of thousands of nuclear genes [11,26], not 100. Moreover, transcripts for photosynthetic functions are generally abundant: for example, the small subunit of RuBisCO and LHC together constitute approximately 20% of all transcripts in Arabidopsis leaves [27].…”