The Spring 2012 season of CACAO has started!

PMID:15028209

From GONUTS
Jump to: navigation, search

Contents

Kleffmann, T, Russenberger, D, von Zychlinski, A, Christopher, W, Sjölander, K, Gruissem, W and Baginsky, S (2004) The Arabidopsis thaliana chloroplast proteome reveals pathway abundance and novel protein functions.Curr. Biol. 14:354-62

Abstract BACKGROUND: Chloroplasts are plant cell organelles of cyanobacterial origin. They perform essential metabolic and biosynthetic functions of global significance, including photosynthesis and amino acid biosynthesis. Most of the proteins that constitute the functional chloroplast are encoded in the nuclear genome and imported into the chloroplast after translation in the cytosol. Since protein targeting is difficult to predict, many nuclear-encoded plastid proteins are still to be discovered. RESULTS: By tandem mass spectrometry, we identified 690 different proteins from purified Arabidopsis chloroplasts. Most proteins could be assigned to known protein complexes and metabolic pathways, but more than 30% of the proteins have unknown functions, and many are not predicted to localize to the chloroplast. Novel structure and function prediction methods provided more informative annotations for proteins of unknown functions. While near-complete protein coverage was accomplished for key chloroplast pathways such as carbon fixation and photosynthesis, fewer proteins were identified from pathways that are downregulated in the light. Parallel RNA profiling revealed a pathway-dependent correlation between transcript and relative protein abundance, suggesting gene regulation at different levels. CONCLUSIONS: The chloroplast proteome contains many proteins that are of unknown function and not predicted to localize to the chloroplast. Expression of nuclear-encoded chloroplast genes is regulated at multiple levels in a pathway-dependent context. The combined shotgun proteomics and RNA profiling approach is of high potential value to predict metabolic pathway prevalence and to define regulatory levels of gene expression on a pathway scale.
Links PubMed
Online version:10.1016/j.cub.2004.02.039

Significance

Annotations

Gene product Qualifier GO ID GO term name Evidence Code with/from Aspect Notes Status


See also

References

See Help:References for how to manage references in GONUTS.

Personal tools
Namespaces
Variants
Actions
Navigation
Cacao
Journal Clubs
Toolbox