Abstract :
[en] Natural trait variation is present across all domains of life. Individuals of the same species often present differences in response to environmental stress or adaptation. Some traits, such as biomass or High Value Molecule production, have economical interest in the industrial, pharmaceutical or agricultural sectors. Identifying the genetic variants affecting important biological processes is, therefore, fundamental.
Chlamydomonas reinhardtii is the reference unicellular photosynthetic eukaryote model organism. C. reinhardtii is a haploid unicellular green alga capable of sexual reproduction, metabolize alternative carbon sources, growing in the dark and under nutrient deficiency. Furthermore, C. reinhardtii has very short generation interval, a high recombination rate and a relatively small genome, making it a suitable organism for a MAGIC design.
In model organisms, genetic variation can be studied using Multiparent Advanced Generation Inter-Cross (MAGIC) designs. In these designs, lines of founders presenting phenotypic variation are intercrossed in a determined design where each founder line contributes equally. This process originates terminal lines where the initial variability is shuffled, forming a genetic mosaic of the founder lines.
Three MAGIC designs, consisting of 8 initial founders intercrossed for 8 generations (F8) were made, and a total of 768 progenies were selected in order to study mineral nutrition. Metal homeostasis is assured by an intricate network of metal uptake, chelation, trafficking, and storage processes. Mixotrophy was used as control condition, and 10 conditions were tested: autotrophy, macronutrient deprivation (Ca, Mg, N, P, S), and micronutrient deprivation (Cu, Fe, Mn, Zn), in 96h assays. Here we present the preliminary results of a small subset.
