References of "Branscheid, Anja"
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See detailStars and symbiosis: microRNA- and microRNA*-mediated transcript cleavage involved in arbuscular mycorrhizal symbiosis.
Devers, Emanuel A.; Branscheid, Anja; May, Patrick UL et al

in Plant Physiology (2011), 156(4), 1990-2010

The majority of plants are able to form the arbuscular mycorrhizal (AM) symbiosis in association with AM fungi. During symbiosis development, plant cells undergo a complex reprogramming resulting in ... [more ▼]

The majority of plants are able to form the arbuscular mycorrhizal (AM) symbiosis in association with AM fungi. During symbiosis development, plant cells undergo a complex reprogramming resulting in profound morphological and physiological changes. MicroRNAs (miRNAs) are important components of the regulatory network of plant cells. To unravel the impact of miRNAs and miRNA-mediated mRNA cleavage on root cell reprogramming during AM symbiosis, we carried out high-throughput (Illumina) sequencing of small RNAs and degradome tags of Medicago truncatula roots. This led to the annotation of 243 novel miRNAs. An increased accumulation of several novel and conserved miRNAs in mycorrhizal roots suggest a role of these miRNAs during AM symbiosis. The degradome analysis led to the identification of 185 root transcripts as mature miRNA and also miRNA*-mediated mRNA cleavage targets. Several of the identified miRNA targets are known to be involved in root symbioses. In summary, the increased accumulation of specific miRNAs and the miRNA-mediated cleavage of symbiosis-relevant genes indicate that miRNAs are an important part of the regulatory network leading to symbiosis development. [less ▲]

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See detailDistribution pattern of small RNA and degradome reads provides information on miRNA gene structure and regulation.
Branscheid, Anja; Devers, Emanuel A.; May, Patrick UL et al

in Plant signaling & behavior (2011), 6(10), 1609-11

Plant microRNAs (miRNAs) have an impact in the regulation of several biological processes such as development, growth and metabolism by negatively controlling gene expression at the post-transcriptional ... [more ▼]

Plant microRNAs (miRNAs) have an impact in the regulation of several biological processes such as development, growth and metabolism by negatively controlling gene expression at the post-transcriptional level. However, the role of these small molecules in the symbiotic interaction of plant roots and arbuscular mycorrhizal (AM) fungi remained elusive. To elucidate the role of miRNAs during AM symbiosis we used a deep sequencing approach to analyze the small RNA and degradome sequence tags of Medicago truncatula non-mycorrhizal and mycorrhizal roots. We identified 243 novel Medicago microRNAs and 118 mRNA cleavage targets of miRNA mature and star sequences. Several AM symbiosis-relevant genes were identified as miRNA targets. The transcript of MtNsp2, encoding a GRAS transcription factor involved in the nodule and mycorrhizal signaling pathway, is cleaved by a novel member of the miR171 gene family, namely miR171h. Here, we carried out a detailed analysis of the genomic structure of the MIR171h gene comprising our deep sequencing data. The results suggest a feedback circuit between mature miR171h and its own primary transcript showing the ability of this miRNA regulating itself. [less ▲]

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See detailExpression pattern suggests a role of MiR399 in the regulation of the cellular response to local Pi increase during arbuscular mycorrhizal symbiosis.
Branscheid, Anja; Sieh, Daniela; Pant, Bikram Datt et al

in Molecular plant-microbe interactions : MPMI (2010), 23(7), 915-26

Many plants improve their phosphate (Pi) availability by forming mutualistic associations with arbuscular mycorrhizal (AM) fungi. Pi-repleted plants are much less colonized by AM fungi than Pi-depleted ... [more ▼]

Many plants improve their phosphate (Pi) availability by forming mutualistic associations with arbuscular mycorrhizal (AM) fungi. Pi-repleted plants are much less colonized by AM fungi than Pi-depleted plants. This indicates a link between plant Pi signaling and AM development. MicroRNAs (miR) of the 399 family are systemic Pi-starvation signals important for maintenance of Pi homeostasis in Arabidopsis thaliana and might also qualify as signals regulating AM development in response to Pi availability. MiR399 could either represent the systemic low-Pi signal promoting or required for AM formation or they could act as counter players of systemic Pi-availability signals that suppress AM symbiosis. To test either of these assumptions, we analyzed the miR399 family in the AM-capable plant model Medicago truncatula and could experimentally confirm 10 novel MIR399 genes in this species. Pi-depleted plants showed increased expression of mature miR399 and multiple pri-miR399, and unexpectedly, levels of five of the 15 pri-miR399 species were higher in leaves of mycorrhizal plants than in leaves of nonmycorrhizal plants. Compared with nonmycorrhizal Pi-depleted roots, mycorrhizal roots of Pi-depleted M. truncatula and tobacco plants had increased Pi contents due to symbiotic Pi uptake but displayed higher mature miR399 levels. Expression levels of MtPho2 remained low and PHO2-dependent Pi-stress marker transcript levels remained high in these mycorrhizal roots. Hence, an AM symbiosis-related signal appears to increase miR399 expression and decrease PHO2 activity. MiR399 overexpression in tobacco suggested that miR399 alone is not sufficient to improve mycorrhizal colonization supporting the assumption that, in mycorrhizal roots, increased miR399 are necessary to keep the MtPho2 expression and activity low, which would otherwise increase in response to symbiotic Pi uptake. [less ▲]

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