Meeting Abstract

S8-1.6  Friday, Jan. 6  Plasticity and the integrated phenotype: examination of integration through development and across environments through classic and genomic approaches MURREN, Courtney J.*; MESSERVY, Jason; STRAND, Allan E.; RUTTER, Matt T.; College of Charleston

Suites of complex characters that work together can be defined as functional modules. Organisms having strong relationships among the traits within a module are hypothesized to have efficient functional performance. Yet integration is not a static feature of an organism, and may vary both across environments and through development. To illustrate the phenotypic variation in integration across environments and through development, we asked: 1) How does integration change through development in three closely related species of Mimulus? Our study uncovered a pivotal contribution of development to integration, but the nature of this contribution varied across species. 2) When the genetic system is perturbed (using T-DNA knock out mutants), how do patterns of integration change through development and across environments? Exploration of genomic perturbations are facile in systems where genomic tools are plentiful, including the suite of SALK T-DNA lines that represent “knockouts” of ~67% of A. thaliana genes. Yet the vast majority of these knockouts display subtle if any morphological phenotypes. This “absence of phenotype” phenomenon has been observed in other model systems. In yeast, researchers turned their focus to complex characters, such as population growth rate and fitness and across environments. For A. thaliana, our preliminary results uncover phenotypes for complex reproductive characters across environments. Comparisons between T-DNA mutants to natural populations and the control line demonstrate that higher integration is observed in natural populations and genomic perturbations reduce integration.