PSC Frontier Seminar series
Title: Control of stem cells in maize and impact on crop yields.
Speaker: Prof. David Jackson, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724, USA
Time: 10:00 am
Day/Date: March 8th, 2019 (Friday)
Host: Jose Rufian-Plaza (Alberto Macho Lab) and Laura Medina-Puche (Rosa Lozano-Duran Lab)
Venue: PSC Auditorium
Plants grow and develop in remarkably challenging and changing conditions, and are critical for our food supply and all life on earth. Plant growth depends upon meristems, pools of stem cells that are maintained in a number of ways, including a negative feedback loop between the CLAVATA pathway and a homeodomain transcription factor, WUSCHEL. CLAVATA signaling involves a secreted peptide, CLAVATA3 (CLV3), and its perception by cell surface leucine-rich repeat (LRR) receptors, including the CLV1 receptor kinase, and an LRR receptor-like protein, CLV2. We are interested in finding novel players in the CLV-WUS pathway, as well as new regulators that could affect meristem size in parallel pathways. Maize is an excellent model system for these studies, because there are many clavata- type mutants, and their isolation is becoming routine. For example, we recently characterized a new CLV-related receptor, FASCIATED EAR3 (FEA3), that appears to function in a different pathway to control meristem size, in parallel to CLV-WUS.
Another interest is in the pathways controlling another yield trait, branching. The classical maize mutant ramosa3 (ra3) has branched ears and more highly branched tassels due to a reduction in meristem determinacy, and encodes a trehalose-6-phosphate phosphatase (TPP) that degrades trehalose-6-phosphate (T6P) to trehalose. T6P has emerged as an important regulator, however, how RA3 controls meristem function remains enigmatic. Our recent data suggests that RA3 interacts with nuclear proteins and may play a moonlighting function in gene regulation. I will discuss the functions of these and other newly identified stem cell regulators, as well as their potential use in improvement of crop yields, for example through enhancing seed number by making weak alleles using promoter CRISPR mutagenesis.
The seminar will be delivered in English.