The phosphoproteome in regenerating protoplasts from Physcomitrella patens protonemata shows changes paralleling postembryonic development in higher plants

J Exp Bot. 2014 May;65(8):2093-106. doi: 10.1093/jxb/eru082. Epub 2014 Apr 3.


The moss Physcomitrella patens is an ideal model plant to study plant developmental processes. To better understand the mechanism of protoplast regeneration, a phosphoproteome analysis was performed. Protoplasts were prepared from protonemata. By 4 d of protoplast regeneration, the first cell divisions had ensued. Through a highly selective titanium dioxide (TiO2)-based phosphopeptide enrichment method and mass spectrometric technology, more than 300 phosphoproteins were identified as protoplast regeneration responsive. Of these, 108 phosphoproteins were present on day 4 but not in fresh protoplasts or those cultured for 2 d. These proteins are catalogued here. They were involved in cell-wall metabolism, transcription, signal transduction, cell growth/division, and cell structure. These protein functions are related to cell morphogenesis, organogenesis, and development adjustment. This study presents a comprehensive analysis of phosphoproteome involved in protoplast regeneration and indicates that the mechanism of plant protoplast regeneration is similar to that of postembryonic development.

Keywords: LC-MS/MS; Physcomitrella patens; TiO2 enrichment.; phosphoproteome; postembryonic development; protoplast regeneration.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bryopsida / genetics
  • Bryopsida / growth & development
  • Bryopsida / physiology*
  • Chromatography, Liquid
  • Phosphoproteins / genetics*
  • Phosphoproteins / metabolism
  • Plant Proteins / genetics*
  • Plant Proteins / metabolism
  • Polymerase Chain Reaction
  • Proteome / genetics*
  • Proteome / metabolism
  • Protoplasts / cytology
  • Protoplasts / physiology*
  • Regeneration
  • Tandem Mass Spectrometry


  • Phosphoproteins
  • Plant Proteins
  • Proteome