A Plant Peptide Encoded by CLV3 Identified by in Situ MALDI-TOF MS Analysis

Abstract

The Arabidopsis CLAVATA3 ( CLV3 ) gene encodes a stem cell–specific protein presumed to be a precursor of a secreted peptide hormone. Matrix-assisted laser desorption/ionization–time-of-flight mass spectrometry (MALDI-TOF MS) applied to in situ Arabidopsis tissues determined the structure of a modified 12–amino acid peptide (MCLV3), which was derived from a conserved motif in the CLV3 sequence. Synthetic MCLV3 induced shoot and root meristem consumption as cells differentiated into other organs, displaying the typical phenotype of transgenic plants overexpressing CLV3 . These results suggest that the functional peptide of CLV3 is MCLV3.