In vitro fluorescent analysis of preprotein import into chloroplasts

Biosci Biotechnol Biochem. 2011;75(10):2001-7. doi: 10.1271/bbb.110438. Epub 2011 Oct 7.

Abstract

Despite recent progress in fluorescence techniques employed to observe protein localization in living cells, the in vitro chloroplastic protein transport assay remains a useful tool for determining the destinations of proteins. Although an in vitro synthesized, radiolabeled precursor protein is frequently used as the transport substrate, we have developed a transport assay system with a non-radiolabeled precursor protein that carries an epitope tag and is overexpressed in Escherichia coli. Thus, a transported protein can be detected by immunoblotting (Inoue et al., Plant Physiol. Biochem., 46, 541-549 (2008)). Here, we propose another in vitro protein transport system that combines fluorescence techniques. We attempted to use two types of precursors: a green fluorescent protein (GFP)-fused precursor and a fluorescent dye-labeled one. Both were successfully imported into chloroplasts. However, the fluorescent dye-labeled precursor was more advantageous than the GFP-fused precursor in the in vitro system.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chloroplast Proteins / metabolism*
  • Chloroplasts / metabolism*
  • Fluoresceins / metabolism
  • Fluorescent Dyes / metabolism
  • Green Fluorescent Proteins / metabolism
  • Pisum sativum / cytology
  • Protein Precursors / metabolism*
  • Protein Transport
  • Spectrometry, Fluorescence / methods*

Substances

  • Chloroplast Proteins
  • Fluoresceins
  • Fluorescent Dyes
  • Protein Precursors
  • Green Fluorescent Proteins
  • fluorescein 5-maleimide