ANALYSING THE FUNCTION AND THE EXPRESSION PATTERN OF AUXIN RESPONSЕ FACTOR B3 FROM MEDICAGO TRUNCATULA IN THE MODEL PLANT LOTUS JAPONICUS

G. Zehirov, M. Revalska, A. Iantcheva, V. Vassileva

Abstract: In plants, Auxin Response Factors (ARFs) regulate gene expression in response to auxin and may act as a transcriptional activators or repressors. ARF proteins bind to auxin response elements (AuxREs) in auxin-responsive gene promoters. Auxin Response Factor B3 from Medicago truncatula (МtARF-B3) was heterologously expressed in the model legume Lotus japonicus. Stable transgenic plants, overexpressing MtARF-B3 and transcriptional reporters were created. In addition, MtARF-B3 ortholog gene of L. japonicus was downregulated and knockdown plants were constructed. Phenotypic and morphological evaluation, quantitative real-time polymerase chain reaction (qRT-PCR) and histochemical GUS assay were used to study the function and expression pattern of MtARF-B3 in the process of somatic embryogenesis and development of tissues and organs. A complex analysis of the obtained results suggests that MtARF-B3 play role in root architecture and in fertility of the model legume L. japonicus.

Keywords: Auxin Response Factor B3; fertility; gene expression; Lotus japonicus; plant development; plant growth

Date published: 2017-08-18