A RAV-like transcription factor controls photosynthesis and senescence in soybean

Abstract

A cDNA library enriched for mRNAs encoding ESTs that increased in abundance during short days was constructed by SSH from leaf tissues of a photoperiod sensitive soybean. The proteins predicted to be encoded by the mRNAs were inferred to be involved in diverse functions. A full-length mRNA that encoded a soybean ortholog of the transcription factor RAV was isolated by RACE, containing an open reading frame of 1,056 bp. The GmRAV protein included an AP2/ERF domain and a B3 domain. GmRAV mRNA abundance was increased in SDs following leaf treatments with ABA and decreased following BR treatment. Transgenic tobacco overexpressing GmRAV showed morphological and physiological alterations such as slower plant growth rate (dwarfing), reduced root elongation, delayed flowering time and reduced photosynthetic rate, reduced chlorophyll contents in leaves. Therefore GmRAV may be a negative regulator acting on both photosynthesis and growth. Transgenic tobacco also showed accelerated senescence with both dark and ABA treatments versus the longer longevity compared to the wild type in LDs. The analyses of soybean leaf, root and stem organs showed that GmRAV mRNA abundances were higher in SDs than in LDs. Therefore, the enhanced expression of GmRAV in SDs compared to LDs may have caused the inhibited growth of soybean leaf, root and stem.

Comparative Analysis of MicroRNA Expression in Three Paulownia Species with Phytoplasma Infection

“…The RAV encodes transcriptional regulators with a variety of functions related to developmental and physiological processes in plants [64,65]. Transgenic tobacco overexpressing RAV showed reduced chlorophyll content and a reduced photosynthetic rate in its leaves [38]. Another DEM, MiR5368g-5p, was down-regulated in PTI and PTFI seedlings.…”

“…In PaWB seedlings, miR160a-5p was down-regulated and the target RAV was up-regulated. In transgenic tobacco, overexpression of a RAV-like orthologue increased cytokinin signaling, which reduced the apical dominance and produced seedlings with dwarfism morphology, whereas inhibition of the RAV-like orthologue produced the opposite phenotype in the seedlings [38,42]. In this study, miR172a-3p and miR172d were down-regulated in the PaWB seedlings, the target gene of miR172a-3p encoded AP2, the target gene of miR172d encoded EREBP, the target genes were up-regulated, and AP2 and EREBP belonged to an AP2/ERF superfamily member.…”

“…MiR160a-5p was down-regulated in PaWB seedlings. The target of this miRNA encodes RAV that was up-regulated, and Zhao [38] showed overexpressing RAV reduced the chlorophyll content and photosynthetic rate in transgenic tobacco leaves. Therefore, this group of miRNAs and their target genes may associate with the reduction of photosynthesis.…”

Isolation and characterization of GoRAV, a novel gene encoding a RAV-type protein in Galegae orientalis

“…GmRAV mRNA abundance increased following leaf treatment with ABA, and decreased following BR treatment. GmRAV transcript abundance in soybean leaves was enhanced during dark-and ABA-induced senescence that caused a decrease in chlorophyll content (Zhao et al, 2008). The expression of the CaRAV1 gene was strongly induced in pepper leaves during early pathogen infection, abiotic elicitors and environmental stress (Kee et al, 2006).…”

Análisis funcional de genes reguladores del desarrollo del fruto y su relación con las vías reguladas por auxinas

“…Algunos miembros de esta familia están relacionados con respuestas a brasinoesteroides Vert et al, 2005) y a etileno (Alonso et al, 2003). Algunos genes de función conocida dentro de la familia RAV son el gen RAV1, que actúa como un regulador negativo del crecimiento y tiempo de floración y que está reprimido por brasinoesteroides (Hu et al, 2004;Zhao et al, 2008), y los genes TEMPRANILLO1 (TEM1) y TEM2 que controlan el tiempo de floración (Castillejo y Pelaz, 2008) Dentro de la familia RAV se encuentra un subgrupo constituido por cuatro genes denominados NGATHA (NGA1-NGA4) que han perdido el dominio AP2 (Alvarez et al, 2006).…”