Project description:Inferring the heritability of gene expression is one of the main areas of the field of genetical genomics. With the possibility to treat the abundances of gene transcripts as a suite of quantitative traits, genetical genomics can make an extensive use of the microarray technology. Here we extended a major method for estimating the heritability of a quantitative trait, single parent-offspring regression, to assess the heritability of the expression of genes with two-channel microarrays. In a series of maternal parent-offspring pairs of Interior spruce (Picea glauca x engelmannii, our focus in the outer stem tissues is the expression of defense-related genes, the heritability of which can affect fitness and necessary for evolution by natural selection.
Project description:The goal of this experiment is to assess tissue preferential transcript accumulation and fold difference between two tissues that support secondary vascular growth in three spruces: Picea glauca, Picea sitchensis and Picea mariana. Tissues compared are secondary xylem (wood forming tissue located on the internal side of the cambial meristem) and phelloderm (composite sample of the phloem and phelloderm tissues located on the outer side of the cambial meristem). One-color comparison of 3 spruce species in 2 tissue types: xylem and phelloderm. 20 biological repetitions per tissue for Picea glauca and 15 for Picea sitchensis and Picea mariana, for a total of 100 slides.
Project description:White pine weevil is a major pest of conifers in North America, especially for Spruce trees. Constitutive defenses are important in understanding defense mechanisms because they constitute the initial barrier to attacks by weevils and other pests. Resistant and susceptible trees exhibit constitutive differences in spruce. To improve our knowledge of their genetic basis, we compared the constitutive expression levels of 17,825 genes between 20 resistant and 20 susceptible trees in interior spruce (Picea glauca).