Plant small RNAs as morphogens

Skopelitis, Damianos S.; Husbands, Aman Y.; Timmermans, Marja C.P.

doi:10.1016/j.ceb.2011.12.006

Cited by 48 publications

(35 citation statements)

References 62 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…5). This novel patterning mechanism suggests that small RNAs have morphogen-like properties (Skopelitis et al, 2012); this scenario is supported by mathematical modeling, which predicts that gradients of mobile small RNAs are uniquely suited to generate sharply defined boundaries of target gene expression (Levine et al, 2007).…”

Section: Cellular Properties Of the Adaxial-abaxial Polarity Networkmentioning

confidence: 85%

The Sussex signal: insights into leaf dorsiventrality

Kuhlemeier

Timmermans

2016

Development

View full text Add to dashboard Cite

The differentiation of a leaf -from its inception as a semicircular bulge on the surface of the shoot apical meristem into a flattened structure with specialized upper and lower surfaces -is one of the most intensely studied processes in plant developmental biology. The large body of contemporary data on leaf dorsiventrality has its origin in the pioneering experiments of Ian Sussex, who carried out these studies as a PhD student in the early 1950s. Here, we review his original experiments in their historical context and describe our current understanding of this surprisingly complex process. Finally, we postulate possible candidates for the 'Sussex signal' -the elusive meristem-derived factor that first ignited interest in this important developmental problem.

show abstract

Section: Cellular Properties Of the Adaxial-abaxial Polarity Networkmentioning

confidence: 85%

The Sussex signal: insights into leaf dorsiventrality

Kuhlemeier

Timmermans

2016

Development

View full text Add to dashboard Cite

show abstract

“…PTGS also is required to modulate the abundance or expression of cellular mRNAs important during developmental transitions, such as the mRNAs targets of the trans-acting small interfering (ta-si)RNA pathway (41,42). Double-stranded (ds)RNA is the priming trigger of PTGS and is generated though several processes such as viral replication, sense-antisense transcription or transcription of inverted-repeat (IR) sequences, whose transcripts are self-complementary and thus fold-back on themselves to form dsRNA.…”

Section: Introductionmentioning

confidence: 99%

Cytoplasmic and nuclear quality control and turnover of single-stranded RNA modulate post-transcriptional gene silencing in plants

Moreno

Alba

Bardou

et al. 2013

Nucleic Acids Research

102

120

View full text Add to dashboard Cite

Eukaryotic RNA quality control (RQC) uses both endonucleolytic and exonucleolytic degradation to eliminate dysfunctional RNAs. In addition, endogenous and exogenous RNAs are degraded through post-transcriptional gene silencing (PTGS), which is triggered by the production of double-stranded (ds)RNAs and proceeds through short-interfering (si)RNA-directed ARGONAUTE-mediated endonucleolytic cleavage. Compromising cytoplasmic or nuclear 5′–3′ exoribonuclease function enhances sense-transgene (S)-PTGS in Arabidopsis, suggesting that these pathways compete for similar RNA substrates. Here, we show that impairing nonsense-mediated decay, deadenylation or exosome activity enhanced S-PTGS, which requires host RNA-dependent RNA polymerase 6 (RDR6/SGS2/SDE1) and SUPPRESSOR OF GENE SILENCING 3 (SGS3) for the transformation of single-stranded RNA into dsRNA to trigger PTGS. However, these RQC mutations had no effect on inverted-repeat–PTGS, which directly produces hairpin dsRNA through transcription. Moreover, we show that these RQC factors are nuclear and cytoplasmic and are found in two RNA degradation foci in the cytoplasm: siRNA-bodies and processing-bodies. We propose a model of single-stranded RNA tug-of-war between RQC and S-PTGS that ensures the correct partitioning of RNA substrates among these RNA degradation pathways.

show abstract

“…tasiR-ARFs normally act preferentially on the adaxial side, and this polarized activity limits arf3 expression to the abaxial side of leaf primordia (Nogueira et al, 2007;Chitwood et al, 2009). In Arabidopsis, the polarized activity of tasiR-ARF reflects a threshold-based readout of a tasiR-ARF gradient generated through the cell-to-cell movement of tasiR-ARFs away from their adaxial source of biogenesis Skopelitis et al, 2012). Whether this is the case in maize remains to be formally shown.…”

Section: Plasticity In Small Rna Regulation Bypasses Selective Constrmentioning

confidence: 99%

Novel DICER-LIKE1 siRNAs Bypass the Requirement for DICER-LIKE4 in Maize Development

et al. 2015

View full text Add to dashboard Cite

Dicer enzymes function at the core of RNA silencing to defend against exogenous RNA or to regulate endogenous genes. Plant DICER-LIKE4 (DCL4) performs dual functions, acting in antiviral defense and in development via the biogenesis of transacting short-interfering RNAs (siRNAs) termed tasiR-ARFs. These small RNAs play an essential role in the grasses, spatially defining the expression domain of AUXIN RESPONSE FACTOR3 (ARF3) transcription factors. However, contrary to tasiRARFs' essential function in development, DCL4 proteins exhibit strong evidence of recurrent adaptation typical of host factors involved in antiviral immunity. Here, we address how DCL4 balances its role in development with pressures to diversify in response to viral attack. We show that, in contrast to other tasiR-ARF biogenesis mutants, dcl4 null alleles have an uncharacteristically mild phenotype, correlated with normal expression of select arf3 targets. Loss of DCL4 activity yields a class of 22-nucleotide tasiR-ARF variants associated with the processing of arf3 transcripts into 22-nucleotide secondary siRNAs by DCL1. Our findings reveal a DCL1-dependent siRNA pathway that bypasses the otherwise adverse developmental effects of mutations in DCL4. This pathway is predicted to have important implications for DCL4's role in antiviral defense by reducing the selective constraints on DCL4 and allowing it to diversify in response to viral suppressors.

show abstract

Plant small RNAs as morphogens

Cited by 48 publications

References 62 publications

The Sussex signal: insights into leaf dorsiventrality

The Sussex signal: insights into leaf dorsiventrality

Cytoplasmic and nuclear quality control and turnover of single-stranded RNA modulate post-transcriptional gene silencing in plants

Novel DICER-LIKE1 siRNAs Bypass the Requirement for DICER-LIKE4 in Maize Development

Contact Info

Product

Resources

About