Application of a proteomic approach to decipher biological processes and functional organellar components for dual-cell photosynthesis in Setaria viridis

CALACE, PAULA; MARGARIT. EZEQUIEL; TONETTI, TOMÁS; FIGUEROA, CARLOS; ANDREO, CARLOS SANTIAGO; GERRARD WHEELER, MARIEL CLAUDIA; SAIGO, MARIANA

Congreso; RAFV XXXIII; 2021

The C4 photosynthesis is typicallycharacterized by the spatial compartmentation of the photosynthetic reactionsinto mesophyll (M) and bundle sheath (BS) cells. The initial carbon fixationgives rise to C4 acids within M cells, which are transported to theBS cells. There, the C4 acids are decarboxylated so that theresulting CO2 is incorporated into the Calvin cycle. This work isfocused on the study of Setaria viridis, a C4 model closerelative of several major feed and bioenergy grasses. According to the peptideidentification and quantification by mass spectrometry, 1,376 proteins wereidentified in M and BS total protein samples. The statistical analysis showedthat 489 proteins were more abundant in M and 336 in BS, which would supportdifferent metabolic scenarios. Gene ontology analysis and subcellular location predictionevidenced significantly different proteomes of chloroplasts, mitochondria andperoxisomes in M and BS. This can be related to the different functions of theorganelles in M and BS compartments and also shows metabolic strategies toinsulate the C4 core to avoid the leakage of intermediates. In this presentationwe describe a useful pipeline to manage proteomic data that uncovered novellines to keep studying and expanding the knowledge on this topic.