Light levels change throughout the day, are affected by climate and weather, and are filtered by the local environment. Switching between low and high levels of light over varying periods of time experienced by an organism in its environment shapes the tempo and mode of its light detection system. Plants must respond to dynamic environmental conditions and thus switch between efficient photosynthesis and photoprotection. Receptors on the plasma membrane perceive extracellular signals, such as photosynthetically-fixed sugars, are coupled to cytoplasmic G proteins to transduce information to cytoplasmic proteins and to amplify that signal to bring about changes like photosynthetic efficiency in both short (e.g. enzymatic reactions) and long (e.g. plant development) time scales. While G proteins have been shown to be important in regulating various aspects of stomata and photosynthesis, their role has yet to be fully understood. A regulator of G signaling (RGS) has been shown to sense sugars fixed in photosynthesis. Thus, we hypothesize that RGS mediates responses to dynamic light. The sequenced genomes within the grass family are the only genomes throughout Plantae known to lack RGS. By contrast, Setaria retains the RGS gene. Thus, the RGS gene from Setaria was expressed in rice to better understand the function of RGS. In this study, multiple transgenic events were grown to investigate their phenotypic response. We identified lines with altered stomatal patterning and rates of stomatal closure in response to changing light levels that will be used in future experiments.

Although plastid genome (plastome) structure is highly conserved across most seed plants, investigations during the past two decades have revealed several disparately related lineages that have experienced substantial rearrangements. Most plastomes have two inverted repeat regions and two single-copy regions with few dispersed repeats. However, the plastomes of some taxa do harbor long repeat sequences (>300 bp). These long repeats make it difficult to assemble complete plastomes using short read data, leading to misassemblies and consensus sequences that have spurious rearrangements. Long read sequencing can potentially overcome these challenges. However, there is no consensus as to the most effective method for accurately assembling plastomes using long read data. Here, we generated a pipeline, plastid Genome Assembly Using Long-read data (ptGAUL) to address the problem of assembling of plastomes using long read data from Oxford Nanopore Technologies (ONT) or Pacific Biosciences (Pacbio) platforms. We demonstrated the efficacy of the ptGAUL pipeline using 16 published long read datasets. We showed that ptGAUL produces accurate and unbiased assemblies. Additionally, we applied ptGAUL to assemble four Juncus (Juncaceae) plastomes using ONT long reads. Our results revealed many long repeats and rearrangements in Juncus plastomes compared with basal lineages of Poales.