A C4 plant K+ channel accelerates stomata to enhance C3 photosynthesis and water use efficiency.

Accelerating stomatal kinetics through synthetic optogenetics and mutations that enhance guard cell K+ flux has proven a viable strategy to improve water use efficiency and biomass production. Stomata of the model C4 species Gynandropsis gynandra, a relative of the C3 plant Arabidopsis thaliana, are similarly fast to open and close. We identified and cloned the guard cell rectifying outward K+ channel (GROK) of Gynandropsis and showed that GROK is preferentially expressed in stomatal guard cells.

Exaptation of ancestral cell-identity networks enables C photosynthesis.

C photosynthesis is used by the most productive plants on the planet, and compared with the ancestral C pathway, it confers a 50% increase in efficiency. In more than 60 C lineages, CO fixation is compartmentalized between tissues, and bundle-sheath cells become photosynthetically activated. How the bundle sheath acquires this alternate identity that allows efficient photosynthesis is unclear.

Streamlined regulation of chloroplast development in the liverwort Marchantia polymorpha.

Chloroplasts develop from undifferentiated plastids in response to light. In angiosperms, after the perception of light, the Elongated Hypocotyl 5 (HY5) transcription factor initiates photomorphogenesis, and two families of transcription factors known as GOLDEN2-LIKE (GLK) and GATA are considered master regulators of chloroplast development. In addition, the MIR171-targeted SCARECROW-LIKE GRAS transcription factors also impact chlorophyll biosynthesis.

MYB-related transcription factors control chloroplast biogenesis.

Chloroplast biogenesis is dependent on master regulators from the GOLDEN2-LIKE (GLK) family of transcription factors. However, glk mutants contain residual chlorophyll, indicating that other proteins must be involved. Here, we identify MYB-related transcription factors as regulators of chloroplast biogenesis in the liverwort Marchantia polymorpha and angiosperm Arabidopsis thaliana.

Advancing Engineered Plant Living Materials through Tobacco BY-2 Cell Growth and Transfection within Tailored Granular Hydrogel Scaffolds.

In this study, an innovative approach is presented in the field of engineered plant living materials (EPLMs), leveraging a sophisticated interplay between synthetic biology and engineering. We detail a 3D bioprinting technique for the precise spatial patterning and genetic transformation of the tobacco BY-2 cell line within custom-engineered granular hydrogel scaffolds. Our methodology involves the integration of biocompatible hydrogel microparticles (HMPs) primed for 3D bioprinting with capable of plant cell transfection, serving as the backbone for the simultaneous growth and transformation of tobacco BY-2 cells.