ARGONAUTE5 Represses Age-Dependent Induction of Flowering through Physical and Functional Interaction with miR156 in Arabidopsis

Abstract Flowering time is a finely tuned process in plants, in part controlled by the age-regulated microRNA156 (miR156), which functions by suppressing the transcripts of SQUAMOSA-PROMOTER BINDING LIKE (SPL) transcription factors. ARGONAUTE (AGO) proteins are essential effectors of miRNA-mediated gene regulation. However, which AGO(s) mediate(s) the control of flowering time remains unclear. Here, we demonstrate a role of AGO5 in controlling flowering time by modulating the expression of SPL transcription factors. We show that AGO5 interacts physically and functionally with miR156 and that ago5 mutants present an early flowering phenotype in Arabidopsis. Furthermore, in ago5 mutants, the repression of flowering caused by miR156 overexpression is largely reversed, whereas leaf morphology remains unaffected. Our results thus indicate a specific role for AGO5 in mediating miR156 activity in meristematic, but not vegetative, tissue. As such, our data suggest a spatiotemporal regulation of the miR156 aging pathway mediated through different AGO proteins in different tissues.

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ARGONAUTE5 Mediates Fine-Tuning of Vegetative-to-Reproductive Phase Transition Through Its Interaction with miR156 in Arabidopsis

10.1101/640680 ◽

2019 ◽

Cited By ~ 1

Author(s):

Charles Roussin-Léveillée ◽

Guilherme Silva-Martins ◽

Peter Moffett

Keyword(s):

Phase Transition ◽

Transcription Factors ◽

Leaf Morphology ◽

Fine Tuning ◽

Vegetative Tissue ◽

Argonaute Proteins ◽

Reproductive Phase ◽

Spatiotemporal Regulation ◽

Different Tissues ◽

Early Flowering Phenotype

ABSTRACTVegetative-to-reproductive phase change is a finely tuned process in plants, largely controlled by the age-regulated microRNA156 (miR156), which functions by suppressing the transcripts of SQUAMOSA-PROMOTER BINDING LIKE (SPL) transcription factors. ARGONAUTE proteins (AGO) are essential effectors of miRNA-mediated gene regulation. However, which AGO(s) mediate(s) the control of flowering time remains unclear. Here, we demonstrate a role for AGO5 in vegetative-to-reproductive phase transition through the modulation of SPL transcription factors. We show that AGO5 interacts physically and functionally with miR156 and that ago5 mutants present an early flowering phenotype in Arabidopsis. Furthermore, in ago5 mutants, the repression of flowering caused by miR156 overexpression is largely reversed, whereas leaf morphology remains unaffected. Our results thus indicate a specific role for AGO5 in mediating miR156 activity in meristematic, but not vegetative, tissue. As such, our data suggest a spatiotemporal regulation of the miR156 aging pathway, mediated through different AGO proteins in different tissues.

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TheYABBYGenes of Leaf and Leaf-Like Organ Polarity in Leafless PlantMonotropa hypopitys

International Journal of Genomics ◽

10.1155/2018/7203469 ◽

2018 ◽

Vol 2018 ◽

pp. 1-16 ◽

Cited By ~ 5

Author(s):

Anna V. Shchennikova ◽

Marya A. Slugina ◽

Alexey V. Beletsky ◽

Mikhail A. Filyushin ◽

Andrey A. Mardanov ◽

...

Keyword(s):

Transcription Factors ◽

Structural Analysis ◽

Mycorrhizal Symbiosis ◽

Vegetative Organs ◽

Qrt Pcr ◽

Physiological Processes ◽

Lateral Organs ◽

Monotropa Hypopitys ◽

Different Tissues

Monotropa hypopitysis a mycoheterotrophic, nonphotosynthetic plant acquiring nutrients from the roots of autotrophic trees through mycorrhizal symbiosis, and, similar to other extant plants, forming asymmetrical lateral organs during development. The members of the YABBY family of transcription factors are important players in the establishment of leaf and leaf-like organ polarity in plants. This is the first report on the identification ofYABBYgenes in a mycoheterotrophic plant devoid of aboveground vegetative organs. SevenM. hypopitys YABBYmembers were identified and classified into four clades. By structural analysis of putative encoded proteins, we confirmed the presence of YABBY-defining conserved domains and identified novel clade-specific motifs. Transcriptomic and qRT-PCR analyses of different tissues revealedMhyYABBYtranscriptional patterns, which were similar to those of orthologousYABBYgenes from other angiosperms. These data should contribute to the understanding of the role of theYABBYgenes in the regulation of developmental and physiological processes in achlorophyllous leafless plants.

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