Plant Proteomics Platform
Proteomic technology allows the isolation and characterisation of the proteome i.e. the protein complement of the genome expressed in an organism, cell or cell fraction in a given time. This technology enables researchers to associate changes in protein expression profiles in different physiological moments and, in this way, it is possible to define the functions of the expressed proteins. Different strategies can be used to analyse proteomes and they depend on the different experimental purposes and on the chemical and physical properties of the target proteins.
The Proteomics platform is conceived to extract protein fractions from plant tissues and resolve them by means of bidimensional electrophoresis techniques (2D-PAGE) after their purification. Besides conventional 2D-PAGE, the platform is equipped with instruments for differential bidimensional electrophoresis (DIGE, Difference Gel Electrophoresis). This technology is particularly well suited for the resolution of complex protein mixtures, allowing for determination of both qualitative and quantitative variations of the samples. After labeling with specific fluorochromes (Cy2, Cy3 e Cy5) different samples can be mixed and then resolved in a unique electrophoretic analysis. The use of an internal standard (i.e. a mixture of all samples) and the high linearity of the response of the three fluorochromes permits a more correct normalization of the results obtained from different analysis. A final experimental phase consists in sample analysis with mass spectrometry (LC-ESI-MS/MS) after partial enzymatic digestion. The processing of all data and subsequent database searching makes peptides identification possible.
Techniques have been developed through conducting researches on proteomes from different plant species (e.g. maize, lupin, pear, peach and grape) that are of notable economic interest. This research aims to elucidate the molecular and biochemical bases of physiological processes related to plant productivity (e.g. nutrient supplying, graft incompatibility and fruit ripening). Several applications will be possible in breeding programs or precise biotechnological interventions. Information from the proteome analysis of edible organs like fruits could be applied to the creation of innovative diagnostic systems for the determination of their organoleptic qualities.
Scientific Director
Prof. Luca Espen is the head scientist of the Plant Proteomic Platform. 1990: Degree in Biological Sciences, University of Florence. 1991-1994: Attends the Ph.D School of Plant Biology and Productivity of Crop Plants, University of Milan. 1995: Obtains Ph.D. title; 1996-1998: Postdoctoral research activity at the University of Milan. 1998: Researcher in Agricultural Chemistry at the University of Milan. Since 2005: Associated Professor in Agricultural Chemistry at the University of Milan. His research activities can be divided into the following topics: a) biochemical and physiological aspects of seed germination; b) heavy metal toxicity; c) biochemical and physiological mechanisms involved in the regulation of dormancy and sprouting of potato tubers d) molecular and biochemical aspects involved in the vascular reconnection of tree plants grafts e) biochemical aspects involved in cellular pH homeostasis during the uptake of mineral nutrients.
Prof. Luca Espen