Reflections on Cyanobacterial Chromatic Acclimation: Exploring the Molecular Bases of Organismal Acclimation and Motivation for Rethinking the Promotion of Equity in STEM

Following the Principles of the Universe: Lessons from Plants on Individual and Communal Thriving

The means by which plants and other organisms exist in and respond to dynamic environments to support their thriving as individuals and in communities provide lessons for humans on sustainable and resilient thriving. First examined in my book, Lessons from Plants (Harvard University Press, 2021), I explore herein the following question: "How can plants teach us to be better humans?" I consider how insights gathered from plant physiology, phenotypic plasticity, and other plant growth phenomena can help us improve our lives and our society, with a focus on highlighting academic and scientific environments. Genetically identical plants can have very different appearances, metabolisms, and behaviors if the external environments in which they are growing differ in light or nutrient availability, among other environmental differences. Plants are even capable of transformative behaviors that enable them to maximize their chances of survival in dynamic and sometimes unfriendly environments, while also transforming the environment in which they exist in the process. Highlighting examples from research on, for instance, plants' responses to light and nutrient cues, I focus on insights for humans derived from lessons from plants. These lessons focus on how plants achieve their own purposes by following common principles of the universe on thriving and resilience as individuals and in communities.

Responding to light signals: a comprehensive update on photomorphogenesis in cyanobacteria

Cyanobacteria are ancestors of chloroplast and perform oxygen-evolving photosynthesis similar to higher plants and algae. However, an obligatory requirement of photons for their growth results in the exposure of cyanobacteria to varying light conditions. Therefore, the light environment could act as a signal to drive the developmental processes, in addition to photosynthesis, in cyanobacteria. These Gram-negative prokaryotes exhibit characteristic light-dependent developmental processes that maximize their fitness and resource utilization. The development occurring in response to radiance (photomorphogenesis) involves fine-tuning cellular physiology, morphology and metabolism. The best-studied example of cyanobacterial photomorphogenesis is chromatic acclimation (CA), which allows a selected number of cyanobacteria to tailor their light-harvesting antenna called phycobilisome (PBS). The tailoring of PBS under existing wavelengths and abundance of light gives an advantage to cyanobacteria over another photoautotroph. In this work, we will provide a comprehensive update on light-sensing, molecular signaling and signal cascades found in cyanobacteria. We also include recent developments made in other aspects of CA, such as mechanistic insights into changes in the size and shape of cells, filaments and carboxysomes.