High impact information on RGL1

• Here, we show that RGL2 regulates seed germination in response to GA, and that RGL1, GAI, and RGA do not [1].
• Repression of GA responses in Arabidopsis was conferred by a dominant 35S-rgl1 transgene carrying a DELLA domain deletion analogous to the GA-insensitive gai-1 mutation [2].
• We found that RGL1 is a similar repressor of GA responses, as revealed by RGL1 gain-of-function and loss-of-function phenotypes [2].
• Conversely, a loss-of-function rgl1 line had reduced GA4 expression and exhibited GA-independent activation of seed germination, leaf expansion, flowering, stem elongation, and floral development, as detected by resistance to the GA biosynthesis inhibitor paclobutrazol [2].
• Foolish seedlings and DELLA regulators: the functions of rice SLR1 and Arabidopsis RGL1 in GA signal transduction [3].

Biological context of RGL1

• Most RGL fragments were found in a clustered or dispersed multi-copy sequence organization, supporting the supposed correlation of RGL sequences and disease resistance loci [4].

Other interactions of RGL1

• Previous studies provided evidence that RGL2 and possibly RGL1 control seed germination [5].
• RGA and, to a lesser extent, GAI mRNAs were expressed ubiquitously in all tissues, whereas RGL1, 2, and 3 transcripts were present at high levels only in germinating seeds and/or flowers and siliques [5].
• We further provided evidence that RGA, RGL1, and RGL2 are all involved in modulating floral development [5].
• The concentrations of bioactive GA(1) and GA(4) in leaves of gai- and rgl1-expressing plants increased 12- to 64-fold, while the C(19) precursors of GA(1) (GA(53), GA(44) and GA(19)) decreased three- to ninefold, consistent with feedback regulation of GA 20-oxidase in the transgenic plants [6].

Analytical, diagnostic and therapeutic context of RGL1

• To investigate further the function of the RGL genes, we examined the expression profiles of all 5 DELLA protein genes by real-time PCR [5].

References