Regulation of the Golden2-like 1 (GLK1) transcription factor

Christopher Großmann ¹, Kerstin Kaufmann ¹

Plant Cell and Molecular Biology, Humboldt-Universität zu Berlin, Institute of Biology, Berlin, Germany ¹

GLK1, a member of the Golden2-like transcription factor family, plays a fundamental role in regulating chloroplast development, photosynthesis, and overall plant growth. Its activity is tightly controlled at multiple levels, including transcriptional, post-transcriptional, and post-translational regulation. Transcriptionally, GLK1 expression is modulated by various environmental cues, like light intensities and temperature. In addition, hormonal signals, and developmental stages play also a role in GLK1 transcriptional regulation, indicating its versatile responsiveness to diverse stimuli. Analysis of transcription factor binding sites revealed that the GLK1 promoter can be divided into three mayor cis-regulatory regions as defined by an open chromatin status. These regions act as hubs for transcription factor binding, with many transcription factors binding to more than one region. To unravel the regulatory regions contributing to developmental, environmental and retrograde-signaling controlled regulation of GLK1, Cas9-based promoter deletions were generated. Stable transgenic lines expressing either promoter or promoter variant-Luciferase fusions, as well as translational fusions with the GLK1 promoter and the genomic locus fused C-terminally to the LUC gene are used to further dissect these environmental signaling pathways.

Main author career stage: PhD student

Contribution type: Poster

First choice session: 4. Structure, physiology, and development

Second choice session: 5. Genetics, genomics, and bioinformatics