Kravchik, M., Institute of Plant Sciences, Agricultural Research Organization, Volcani Center, PO Box 6, Bet Dagan 50250, Israel
Sunkar, R., Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK 74078, United States
Damodharan, S., Institute of Plant Sciences, Agricultural Research Organization, Volcani Center, PO Box 6, Bet Dagan 50250, Israel
Stav, R., Institute of Plant Sciences, Agricultural Research Organization, Volcani Center, PO Box 6, Bet Dagan 50250, Israel
Zohar, M., Unit of Deciduous Fruit Tree Sciences, Newe ya'Ar Research Center, Agricultural Research Organization, PO Box 1021, Ramat Yishay 30095, Israel
Isaacson, T., Unit of Deciduous Fruit Tree Sciences, Newe ya'Ar Research Center, Agricultural Research Organization, PO Box 1021, Ramat Yishay 30095, Israel
Arazi, T., Institute of Plant Sciences, Agricultural Research Organization, Volcani Center, PO Box 6, Bet Dagan 50250, Israel
Sunkar, R., Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK 74078, United States
Damodharan, S., Institute of Plant Sciences, Agricultural Research Organization, Volcani Center, PO Box 6, Bet Dagan 50250, Israel
Stav, R., Institute of Plant Sciences, Agricultural Research Organization, Volcani Center, PO Box 6, Bet Dagan 50250, Israel
Zohar, M., Unit of Deciduous Fruit Tree Sciences, Newe ya'Ar Research Center, Agricultural Research Organization, PO Box 1021, Ramat Yishay 30095, Israel
Isaacson, T., Unit of Deciduous Fruit Tree Sciences, Newe ya'Ar Research Center, Agricultural Research Organization, PO Box 1021, Ramat Yishay 30095, Israel
Arazi, T., Institute of Plant Sciences, Agricultural Research Organization, Volcani Center, PO Box 6, Bet Dagan 50250, Israel
DICER-like 1 (DCL1) is a major player in microRNA (miRNA) biogenesis and accordingly, its few known loss-of-function mutants are either lethal or display arrested development. Consequently, generation of dcl1 mutants by reverse genetics and functional analysis of DCL1 in late-developing organs are challenging. Here, these challenges were resolved through the unique use of trans-activated RNA interference. Global, as well as organ-specific tomato DCL1 (SlDCL1) silencing was induced by crossing the generated responder line (OP:SlDCL1IR) with the appropriate driver line. Constitutive trans-activation knocked down SlDCL1 levels by ∼95%, resulting in severe abnormalities including post-germination growth arrest accompanied by decreased miRNA and 21-nucleotide small RNA levels, but prominently elevated levels of 22-nucleotide small RNAs. The increase in the 22-nucleotide small RNAs was correlated with specific up-regulation of SlDCL2b and SlDCL2d, which are probably involved in their biogenesis. Leaf- and flower-specific OP:SlDCL1IR trans-activation inhibited blade outgrowth, induced premature bud senescence and produced pale petals, respectively, emphasizing the importance of SlDCL1-dependent small RNAs in these processes. Together, these results establish OP:SlDCL1IR as an efficient tool for analysing processes regulated by SlDCL1-mediated gene regulation in tomato. © © The Author 2013. Published by Oxford University Press on behalf of the Society for Experimental Biology.
