Difference between revisions of "IC4R012-miRNA-2009-20017947"
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==Research Findings== | ==Research Findings== | ||
| − | *The mature miR172a-d sequences differ only in their 5' and 3' bases and therefore hybridization with a miR172a probe is likely to detect expression of all mature miR172 sequences. In wild-type plants, miR172 expression varied considerably between organs and developmental stages.Mature miR172 accumulation increased significantly in leaves but not in roots as plants grew, reaching a maximum in the flag leaf (Figure 1A). | + | *The mature miR172a-d sequences differ only in their 5' and 3' bases and therefore hybridization with a miR172a probe is likely to detect expression of all mature miR172 sequences. In wild-type plants, miR172 expression varied considerably between organs and developmental stages.Mature miR172 accumulation increased significantly in leaves but not in roots as plants grew, reaching a maximum in the flag leaf (Figure 1A).Similar expression patterns of miR172 have also been observed in vegetative tissues of Arabidopsis and maize [13,17], suggesting that miR172 has a conserved role during vegetative development. In reproductive tissues, miR172 was consistently expressed although its abundance reduced gradually during panicle development (Figure 1B). Expression of miR172 was below the detection limit in 10 DAF (daysafter-fertilization) grains (Figure 1B). |
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==Labs working on this Project== | ==Labs working on this Project== | ||
Revision as of 02:25, 15 July 2016
Contents
Project Title
- Over-expression of miR172 causes loss of spikelet determinacy and floral organ abnormalities in rice (Oryza sativa)
The Background of This Project
- Regulation of gene expression by microRNAs (miRNAs) plays a crucial role in many developmental and physiological processes in plants. miRNAs act to repress expression of their target genes via mRNA cleavage or translational repression. Dozens of miRNA families have been identified in rice, 21 of which are conserved between rice and Arabidopsis. miR172 is a conserved miRNA family which has been shown to regulate expression of APETALA2 (AP2)-like transcription factors in Arabidopsis and maize. The rice genome encodes five AP2-like genes predicted to be targets of miR172. To determine whether these rice AP2-like genes are regulated by miR172 and investigate the function of the target genes, the researchers studied the effect of over-expressing two members of the miR172 family on rice plant development.
Plant Culture & Treatment
- All experiments were performed using rice (Oryza sativa spp. japonica) cultivar Nipponbare. Rice tissue samples were collected from plants grown in a controlled glasshouse at 25 ± 3°C with 16 hours of light, except the twoleaf-stage shoots and roots that were collected from young seedlings grown in Petri dishes at 28°C. For miR172 overexpression transgenic lines, mature leaves (for northern blot) and panicle samples (for qRT-PCR) were collected from T 0 plants. The two-leaf-stage shoot sample included shoot apices and all leaves. The 10-leaf-stage shoot apex sample included the basal ~0.5 cm part of young leaves that are ~1 cm in length. Two-, four- and ten-leaf-stage samples were used to represent juvenile, intermediate and adult vegetative stage, respectively. Panicles with a length of less than 0.5 cm and 0.5-4 cm represent differentiation stage of spikelets and florets, respectively. Booting panicle was representative of developed panicle.
Research Findings
- The mature miR172a-d sequences differ only in their 5' and 3' bases and therefore hybridization with a miR172a probe is likely to detect expression of all mature miR172 sequences. In wild-type plants, miR172 expression varied considerably between organs and developmental stages.Mature miR172 accumulation increased significantly in leaves but not in roots as plants grew, reaching a maximum in the flag leaf (Figure 1A).Similar expression patterns of miR172 have also been observed in vegetative tissues of Arabidopsis and maize [13,17], suggesting that miR172 has a conserved role during vegetative development. In reproductive tissues, miR172 was consistently expressed although its abundance reduced gradually during panicle development (Figure 1B). Expression of miR172 was below the detection limit in 10 DAF (daysafter-fertilization) grains (Figure 1B).
Labs working on this Project
- CSIRO Plant Industry, GPO Box 1600, Canberra, ACT 2601, Australia
Corresponding Author
- Qian-Hao Zhu:qianhao.zhu@csiro.au & Narayana M Upadhyaya:narayana.upadhyaya@csiro.au & Frank Gubler: frank.gubler@csiro.au & Chris A Helliwell:chris.helliwell@csiro.au
