Elif KARLIK, Cuneyt UCARLI, Filiz GUREL, Semian Karaer UZUNER, Muhammad Qasim SHAHID

SILENCING OF G-PROTEIN ?-SUBUNIT IN BARLEY (Hordeum vulgare L.) BY VIGS AND ITS EFFECT ON THE PLANT GROWTH

G-proteins play important roles in a number of cellular and developmental processes in plants. In this study, we have cloned a 317-bp fragment encoding a part of barley G protein ?-subunit into ?-genome of barley stripe mosaic virus (BSMV). Barley seedlings were inoculated with this construct denoted as pSL038-1/G? at 3-leaf stage, and assayed for their growth, leaf area and membrane ion leakage. Silencing was achieved after 2 weeks of inoculation and confirmed by the decrease in G? subunit mRNAs in barley leaves. There was a significant decrease in plant growth in terms of plant height and leaf area following the viral infection. Leaf area in silenced plants were decreased by >10% compared to control plants (wild-type or inoculated by BSMV-PDS constructs). In conclusion, silencing resulted in etiolated phenotypes and growth retardation. Our optimized VIGS protocol in barley could be adopted to evaluate extensive physiological parameters and molecular changes in G? silenced plants.

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