Entries by Patrice Salome

Mediator Skills: MED16 Controls Endoreduplication

The discovery of Mediator began with the observation that two transcriptional activators could interfere with each other’s function in vitro, even though they did not bind to the same promoter (Kelleher, Flanagan and Kornberg, 1990). The hypothesis, since then well-validated, was that each transcription factor titrates components (i.e., Mediator) critical for the proper initiation of […]

Too Close to the Flame: Duplicated ICARUS Genes and Growth at Higher Temperatures

Plants can adjust their growth and reproduction cycles according to the local climate they experience, but how will they respond when ambient temperatures rise? Most Arabidopsis accessions respond by increasing cell elongation and accelerated flowering, but some cannot cope with higher temperatures and stop growing. Such was the premise that led to the cloning of […]

Plants on (Brassinos)steroids: Degradation of the Transcription Factor BZR1 by the E3 Ubiquitin Ligase PUB40

Brassinosteroids (BR) are the only plant hormones with an animal counterpart: steroid hormones. Analysis of BR signaling demonstrated that steroid receptors could reside at the plasma membrane and modulate growth and gene expression, an observation that is now becoming appreciated in non-plant systems (Levin and Hammes, 2016). Our understanding of BR signaling in Arabidopsis thaliana […]

The shade of things to come: plastid retrograde signaling and shade avoidance

Plants compete with each other over finite resources like water and nutrients, but also for sunlight when they grow in each other’s shadow. Light filtered through leaves is rich in far-red light and initiates responses, known as shade avoidance syndrome (SAS), that aim to out-compete neighbors by promoting hypocotyl elongation and returning the plant to […]

Divide and Conquer: High-Throughput Screening of Chlamydomonas Cell Cycle Mutants

Cell division is essential for growth and reproduction. The cell cycle machinery is well conserved between yeast and animals, but whether this conservation extends to the plant lineage is not clear, having diverged over two billion years ago: ample time and opportunity for divergence in sequence and function, and for introduction of plant-specific innovations. Discovering […]

Developmental Timing is Everything: TZP and Phytochrome Signaling

Although they lack eyes, plants can differentiate between colors with a full complement of photoreceptors. Phytochromes (phys) are such photoreceptors dedicated to the visible light spectrum ranging from red light (600-700 nm) to far-red light (700-750 nm). phys are some of the most studied genes and control plant architecture and flowering time. phyA is a […]

Hold Me Closer: Meiotic Crossover Formation and FANCD2

Meiosis takes a single, diploid cell and turns it into four haploid spores. The equal distribution of genetic material is critical for genome stability across generations, and relies heavily on proper pairing of chromosomes and their timely release. During the first meiotic division, crossovers (COs) are responsible both for the exchange of genetic material between […]

Proliferate at Your Own Risk: Ribosomal Stress and Regeneration

Plant growth and development are extremely adaptable to changes in the external environment, including nutrient status, light quality and intensity, and temperature. Thanks to their developmental plasticity, plants can also initiate new organs from differentiated tissue following wounding, to the benefit of horticulturists everywhere. Plants establish a balance between cell proliferation and cell growth that […]