(100-106) VERNALIZATION INDEPENDENCE 3 (VIP3): the first plant gene shown to play a role in deacclimation resistance in arabidopsis and canola - Lightning Talk
Body of Abstract: Winter canola showed increased freezing tolerance if they are first acclimated to low non-freezing temperatures for several weeks. However, if fully acclimated plants are exposed to warmer temperatures for several days, they lose freezing tolerance in a process called deacclimation. During late winter and early spring, short stretches of warmer temperatures could result in deacclimation. If the temperature then drops below freezing, the plant could die. Due to global warming, these scenarios could be seen more frequently. Winter canola showed variation among genotypes in response to deacclimation rate, and deacclimation was unrelated to cold acclimation ability. Genome-wide association mapping implicated a gene similar to VERNALIZATION INDEPENDENCE 3 (VIP3) as being associated with deacclimation rate. Two independent arabidopsis lines with insertion mutations in VIP3 both showed better deacclimation resistance than wild type. VIP3 mutants were shown to have some minimal impact on flower timing by activating MADS-box genes. RNA-seq indicated no genes were significantly differentially expressed in both mutants as compared to wild type following cold acclimation. However, 243 genes were shown to be significantly differentially regulated in both mutants as compared to wildtype following deacclimation. Interestingly, three of the four originally cloned cold regulated genes of arabidopsis were up regulated in both mutants compared to wild type as were other genes previously described as targets of the VIP3 regulation, but none of the CBF genes were significantly up regulated in the deacclimated mutants. We are still investigating the mechanism for down regulation of COR genes in wildtype following deacclimation. We will also report on progress to knockout VIP3 by CRISPR-cas9 technology in deacclimation susceptible canola lines to confirm the role of VIP3 in canola deacclimation.