Analysis of MAPK expression in Arabidopsis thaliana seedlings.

Severina Pociunaite,Institute of Biotechnology, Vilnius, Lithuania

Severina Marija Pociuniate, Kotryna Kvederaviciute, Armin Djamei, Alois Schweighofer, and Irute Meskiene

Mitogen-activated protein kinases (MAPKs) play an essential role in growth-related signaling cascades in eukaryotes, including plants. MAPKs are controlling the cell cycle and developmental processes. In plants MAPKs signaling pathways are the most studied in Arabidopsis thaliana. One of these pathways is related to stem cell initiation and differentiation during stomata development. Stomata are cells located on the leaf epidermal surface responsible for plant gas exchange and water transport. Expression analysis of MAPKs during stomata development has not been performed so far. MAPK expression studies in roots also wait to be investigated. The question remains, when and where these central signaling components are expressed during seedling development. The aim of this study is to identify the cells where MAPKs are expressed and to determine changes of gene expression during seedling development. The results of ongoing study are presented and demonstrate the regulation of MAPK gene expression. In this study we are using transgenic Arabidopsis plant lines expressing different MAPKprom::GUS (- glucuronidase) reporter cassettes. Results presented here are demonstrating regulation of MAPK gene induction in different tissues and in specific cells during different stages of seedling development. Monitoring expression of MAPK genes at different plant developmental stages provides an insight towards the function of MAPKs during proliferation/differentiation processes. Using the well-established promoter::GUS reporter method enables easy detection of protein expression by optical microscope. Our results provide new information about specific roles of different MAPKs during cell signaling processes in plant development.