Matrix-assisted laser desorption/ionisation mass spectrometry imaging and its development for plant protein imaging

Abstract

Matrix-Assisted Laser Desorption/Ionisation (MALDI) mass spectrometry imaging (MSI) uses the power of high mass resolution time of flight (ToF) mass spectrometry coupled to the raster of lasers shots across the cut surface of tissues to provide new insights into the spatial distribution of biomolecules within biological tissues. The history of this technique in animals and plants is considered and the potential for analysis of proteins by this technique in plants is discussed. Protein biomarker identification from MALDI-MSI is a challenge and a number of different approaches to address this bottleneck are discussed. The technical considerations needed for MALDI-MSI are reviewed and these are presented alongside examples from our own work and a protocol for MALDI-MSI of proteins in plant samples.

Cyclotides Associate with Leaf Vasculature and Are the Products of a Novel Precursor in Petunia (Solanaceae)

“…Cryosectioning-Petunia leaf tissue was prepared for MALDI imaging with minor changes to a method described previously (37). Samples were cryosectioned using a Leica CM3050 cryotome with chamber temperature set at Ϫ19°C and object temperature set at Ϫ17°C.…”

MALDI Mass Spectrometry Imaging for the Simultaneous Location of Resveratrol, Pterostilbene and Viniferins on Grapevine Leaves

“…In just a few years, mass spectrometry imaging (MSI) made the dream of the location of molecular compounds at the micron scale to come true [2,3]. First developed on animal slices [4,5], this emerging technique finds a growing interest in plant proteomic [6] and metabolomic [7][8][9]. Indeed, MSI is able to provide a specific spatial distribution of proteins or metabolites in tissues.…”

Metabolic flux analysis using 13C peptide label measurements

“…Detailed spatially resolved flux maps may be achieved with PMD-based flux analysis in combination with MS imaging. MS imaging is becoming an established technology in plant biology that has the ability to determine protein masses that are unique to a cell type with micrometer resolution (Jun et al, 2010;Grassl et al, 2011;Kaspar et al, 2011). Once identified, a protein may be used for a flux map specific to the location where it was observed.…”