S01 - Session P1 - Expression analysis of a mitogen-activated protein kinase (MAPKs) gene family in grapevine berries

Authors: Ashkan Hodaei *, stefaan Werbrouck, Birsen Cakir

Plants, as sessile living organisms, depend on signalling mechanisms for their interaction with the environment. Mitogen-activated protein kinases ( MAPK s) are a highly conserved family of genes that play a role in converting an extracellular signal into an intercellular signal. Ripening-related processes are not as well understood in non-climacteric fruits as in climacteric fruits. In this respect, studying MAPKs in grape berries during developmental stages may lead to a better understanding of physiological interactions during commercially relevant stages, such as pigmentation, ripening and phenol accumulation in the berries. Each MAPK cascade includes three or four MAPK proteins that facilitate signal transduction by phosphorylation of downstream targets. We examined the relative expression of VvMAP2K s and VvMAP4K s in berries at two-week intervals from flowering to overripening. Expression analysis of 5 MAP2K s and 7 MAP4K s suggested that both gene families may play an active role in berry development. Expression of VvMAP2K1 showed a correlation with abscisic acid (ABA) and ethylene accumulation. The expression pattern of VvMAP2K2 and VvMAP2K3 showed a correlation with auxin and ABA accumulation, respectively. In addition, VvMAP2K4 may play a role in increasing berry size and arresting stomatal development. Moreover, VvMAP2K5 might play a role in the development of flower organs. The expression pattern of VvMAP4K s makes them excellent markers for monitoring the effect of, for example, climate change-related stress on berry development.