Plant & Animal Genomes XVII Conference

January 10-14, 2009
Town & Country Convention Center
San Diego, CA

Structure And Regulation Of The Abscisic Stress Ripening (ASR) Gene Family In Banana

Isabelle, M Henry , Sebastien, C Carpentier , Bart Panis , Rony Swennen , Serge Remy

  Laboratory of Tropical Crop Improvement Katholieke Universiteit Leuven Kasteelpark Arenberg 13 bus 2455 3001 Leuven, Belgium

Drought, high salinity and freezing all impose osmotic stress on plants and negatively affect their growth, development and productivity. This is particularly true for bananas for which typical effects include lower yields, decreased number and length of fruits, delay in flowering and shortening of fruit shelf life. To investigate the mechanisms behind the response of banana to osmotic stress, a large scale proteomics study was undertaken and 66 proteins were identified that were significantly up or down regulated in response to high sugar treatments of banana meristems. One of the most abundant proteins identified was an Abscisic Stress Ripening (ASR) protein. ASR proteins are plant-specific and have been associated with abiotic stress response in various species. We further investigated the ASR gene family in banana and identified 4 members from the Musa genome (mASRs). Phylogenetic analysis of ASR sequences from different cultivars suggests that the four mASRs are more closely related to each other than they are to ASR sequences from other species. Q-PCR analysis revealed that the regulation of mASRs varies between cultivars and between tissues. Furthermore, 2D gel electrophoresis suggested that mASR1 is one of the most abundant proteins in meristem cultures of a dehydration tolerant variety but it could not be detected in a dehydration sensitive variety. Lastly, the presence of the protein appears to be associated with the B genome. Further experiments examining the regulation of ASR and its possible role in drought and osmotic stress resistance are ongoing and will be discussed.