Long-distance movement of phosphate starvation-responsive microRNAs in Arabidopsis.
Plant microRNAs are small RNAs that are important for genetic regulation of processes such as plant development or environmental responses. Specific microRNAs accumulate in the phloem during phosphate starvation, and may act as long-distance signalling molecules. We performed quantitative PCR on Arabidopsis hypocotyl micrograft tissues of wild-type and hen1-6 mutants to assess the mobility of several phosphate starvation-responsive microRNA species. In addition to the previously confirmed mobile species miR399d, the corresponding microRNA* (miR399d*) was identified for the first time as mobile between shoots and roots. Translocation by phosphate-responsive microRNAs miR827 and miR2111a between shoots and roots during phosphate starvation was evident, while their respective microRNA*s were not mobile. The results suggest that long-distance mobility of microRNA species is selective and can occur without the corresponding duplex strand. Movement of miR399d* and root-localised accumulation of miR2111a* opens the potential for persisting microRNA*s to be mobile and functional in novel pathways during phosphate starvation responses.
Plant Molecular Biology Lab, School of Life and Environmental Sciences, The University of Sydney, Camperdown, NSW, Australia.
A K
http://orcid.org/0000-0003-3924-1461
AK
Huen
The Colombian Agricultural Research Corporation (Corpoica), Palmira, Valle del Cauca, Columbia.
C
C
Rodriguez-Medina
Plant Molecular Biology Lab, School of Life and Environmental Sciences, The University of Sydney, Camperdown, NSW, Australia.
A Y Y
AYY
Ho
Centre for Plant Genetics and Breeding, The University of Western Australia, Crawley, Perth, WA, Australia.
C A
CA
Atkins
Plant Molecular Biology Lab, School of Life and Environmental Sciences, The University of Sydney, Camperdown, NSW, Australia.
P M C
PMC
Smith
D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics; D018506:Gene Expression Regulation, Plant / Q000235:genetics; D035683:MicroRNAs / Q000235:genetics*; D052585:Phloem / Q000235:genetics / Q000378:metabolism; D010710:Phosphates / Q000378:metabolism*; D018517:Plant Roots / Q000235:genetics / Q000378:metabolism; D018749:RNA, Plant / Q000235:genetics
D029681:Arabidopsis Proteins; D035683:MicroRNAs; D010710:Phosphates; D018749:RNA, Plant
Abiotic stress; microRNA; non-cell autonomous; phloem; small RNA; transport