R. A. Mosher

Control of cell fate specification and patterning by an ancestral microRNA

The paper shows that MpDCL1a is essential for miRNA biogenesis and regulates auxin synthesis, influencing cell identity and body development in the last common ancestor of land plants.

Mating system is associated with seed phenotypes upon loss of RNA-directed DNA Methylation in Brassicaceae

The paper investigates how the mating system affects seed production defects in RdDM mutants across Brassicaceae species, finding that outcrossing species show similar defects while selfing species do not.

Charophytic Green Algae encode ancestral Pol IV/Pol V subunits and a CLSY/DRD1 homolog

The paper identifies ancestral Pol IV/Pol V subunits and a CLSY/DRD1 homolog in Charophytic green algae, suggesting a single Pol V-like polymerase in early RdDM.

Mapping a mutation causing pale yellow petals in Brassica rapa

The paper identifies a mutation in Brassica rapa causing pale yellow petals through genetic mapping and functional analysis.

A novel CLAVATA1 mutation causes multilocularity in Brassica rapa

This study identifies a CLAVATA1 mutation in Brassica rapa that increases locule number and disrupts floral meristem termination.

A Null Allele of the Pol IV Second Subunit is Viable in Oryza sativa

This study identifies a null allele of NRPD2 in Oryza sativa, showing it is essential for small RNA production and CHH methylation in leaves, but not for gametophytic function or embryo viability.

Ovule siRNAs methylate protein-coding genes in trans

The paper shows that ovule-derived 24-nt siRNAs can methylate protein-coding genes in trans, leading to gene silencing and seed abortion in RdDM mutants.

Embryo CHH hypermethylation is mediated by RdDM and is autonomously directed in Brassica rapa

This study shows that embryo CHH hypermethylation in Brassica rapa is autonomously controlled by RdDM and not influenced by maternal sporophyte factors.

Abundant expression of maternal siRNAs is a conserved feature of seed development

The paper shows that maternal siRNAs are abundant and conserved in seed development across angiosperms, with a maternal bias in endosperm and dependence on RNA Pol IV/RDR2.

Evidence for a unique DNA-dependent RNA polymerase in cereal crops

The paper identifies a unique DNA-dependent RNA polymerase complex in grasses, showing evidence of duplication and functional divergence in cereal crops.

Maternal RNA-directed DNA methylation is required for seed development in Brassica rapa

This study shows that maternal small RNA pathway mutations cause seed abortion in Brassica rapa, revealing a role for maternal somatic tissues in seed development through RNA-directed DNA methylation.