Engineering quantitative stomatal trait variation and local adaptation potential by cis-regulatory editing.

Cis-regulatory element editing can generate quantitative trait variation that mitigates extreme phenotypes and harmful pleiotropy associated with coding sequence mutations. Here, we applied a multiplexed CRISPR/Cas9 approach, informed by bioinformatic datasets, to generate genotypic variation in the promoter of OsSTOMAGEN, a positive regulator of rice stomatal density. Engineered genotypic variation corresponded to broad and continuous variation in stomatal density, ranging from 70% to 120% of wild-type stomatal density.

Multiplexed CRISPR-Cas9 mutagenesis of rice noncoding sequences for transgene-free overexpression.

Understanding CRISPR-Cas9's capacity to produce native overexpression (OX) alleles would accelerate agronomic gains achievable by gene editing. To generate OX alleles with increased RNA and protein abundance, we leveraged multiplexed CRISPR-Cas9 mutagenesis of noncoding sequences upstream of the rice gene. We isolated 120 gene-edited alleles with varying non-photochemical quenching (NPQ) capacity in vivo-from knockout to overexpression-using a high-throughput screening pipeline.

Paralog editing tunes rice stomatal density to maintain photosynthesis and improve drought tolerance.

Rice (Oryza sativa) is of paramount importance for global nutrition, supplying at least 20% of global calories. However, water scarcity and increased drought severity are anticipated to reduce rice yields globally. We explored stomatal developmental genetics as a mechanism for improving drought resilience in rice while maintaining yield under climate stress.

An Agrobacterium-mediated stable transformation technique for the hornwort model Anthoceros agrestis.

Despite their key phylogenetic position and their unique biology, hornworts have been widely overlooked. Until recently there was no hornwort model species amenable to systematic experimental investigation. Anthoceros agrestis has been proposed as the model species to study hornwort biology.

Agrobacterium tumefaciens-Mediated Transformation of Tomato.

Tomato is both an important food crop and serves as a model plant species that is used for various research investigations including understanding gene function. Transformation is commonly utilized to facilitate these investigations in combination with all the extensive genetic and genomic resources available for tomato. The transformation protocol routinely used in our laboratory has been applied to many different tomato genotypes and relies on Agrobacterium tumefaciens infection of young cotyledon sections.

SUPPRESSOR OF GAMMA RESPONSE1 Links DNA Damage Response to Organ Regeneration.

In Arabidopsis, DNA damage-induced programmed cell death is limited to the meristematic stem cell niche and its early descendants. The significance of this cell-type-specific programmed cell death is unclear. Here, we demonstrate in roots that it is the programmed destruction of the mitotically compromised stem cell niche that triggers its regeneration, enabling growth recovery.