Date: 17th January 2018
Title: Peptide signalling pathways controlling floral abscission
Location: Biocentre 2, seminar room 1015, Viikinkaari 5
Host: Michi Wrzaczek
Abstract: Signalling pathways involved in floral abscission and defence. The research activities in my lab have a focus on how plants use small peptide ligands and plasma-membrane receptor proteins to regulate important developmental processes and to respond to both biotic and abiotic stresses. The lab has for a long time worked on elucidating the genetic networks that controls abscission (organ loss) of Arabidopsis floral organs. Abscission is an active, highly regulated process in the life span of a plant and has a variety of roles during plant development. Roles such as efficient dispersal or propagation of the plant secured by the shedding of pollen, fruits, and seeds; The shedding of unwanted or unneeded organs, such as the flower after aiding in pollination, And lastly damaged or infected organs may be rapidly shed as a defence mechanism. In Arabidopsis floral abscission is tightly regulated by the peptide ligand INFLORESCENCE DEFICIENT IN ABSCISSION (IDA) relaying a signal through the Leucine-rich repeat (LRR) receptor-like kinases (RLK) HAESA (HAE) and HAESA-LIKE 2 (HSL2) and inducing a signalling cascade including MAP kinases, MADS box and KNOX transcription factors. Recent work in the lab indicates a role for the IDA signalling pathway as a mediator of stress induced responses such as pathogens. The RLK FLS2 recognizes the pathogen-associated molecular pattern flagellin (flg22), a bacterial surface protein, and induces an immune response in planta. Here the connection between the FLS2 and HAE/HSL2 signalling pathways will be presented.
Melinka Butenko is Associate Professor of Molecular Biology and Genetics at the University of Oslo, section for Genetics and Evolutionary Biology. Melinka Butenko leads a group with two main research interests. One part of the lab is focused on understanding how peptide ligands and receptor signalling control plant growth, architecture and development with a specific focus on processes involving cell separation and cell wall remodeling, such as those that occur during abscission. Currently dissecting the components of the signal transduction cascade leading to abscission and their potential crosstalk to stress induced pathways is in focus. The other main research area of the lab is the investigation of the functional modulation of regulatory mechanisms affecting the phenotype by variations in simple trinucleotide repeats residing inside (coding) and in the vicinity (or in introns) of genes. Specifically, we are testing the hypothesis that hypervariable coding/regulatory repeats are promoting the ability of a species or population to adapt to a changing environment. To address this we use Arabidopsis and Atlantic cod as model systems, in a collaborative effort together with researchers at the Centre for Ecological and Evolutionary Synthesis (CEES).