Use of androgenesis for estimating maternal and mitochondrial genome effects on development and oxygen consumption in rainbow trout, Oncorhynchus mykiss

Quantitative Trait Loci × Maternal Cytoplasmic Environment Interaction for Development Rate in Oncorhynchus mykiss

“…Research in many organisms has shown that mitochondrial haplotype (Gerber et al 2001;Brown et al 2006), maternal hormones (Eising et al 2001), and maternal mRNA in eggs (Nagler 2000) can influence embryonic development. Variation in mitochondrial haplotypes can affect rate of development, oxygen consumption, growth, and fitness independent of nuclear genetic background as well as by interaction with the nuclear genome (Gerber et al 2001;Brown et al 2006; and references therein).…”

“…Variation in mitochondrial haplotypes can affect rate of development, oxygen consumption, growth, and fitness independent of nuclear genetic background as well as by interaction with the nuclear genome (Gerber et al 2001;Brown et al 2006; and references therein). Androgens, corticosteriods, and thyroid hormones are among the maternally derived hormones with significant roles during embryonic development in vertebrates.…”

“…Furthermore, egg size alone does not encompass many maternally derived egg components that may significantly affect development rate. More recently, using the same rainbow trout clonal line system described herein, variation in mitochondrial haplotype in a constant nuclear background has shown significant association with variation in development rate, suggesting that the mitochondrial haplotype alone can influence the rate of development (Brown et al 2006). Here, we aim to determine if the egg source, or maternal cytoplasmic environment (MCE) in total, significantly affects the expression of quantitative trait loci (QTL) associated with development rate in Oncorhynchus mykiss.…”

“…Female mate choice, maternal care, maternal allocation of resources, maternal transfer of cytoplasmic factors to eggs and young, and the influence of environment on female reproduction all have important implications for the survival of developing offspring. Maternal effects play an important role in the early development of salmonid fishes Fleming 2000, 2004;Brown et al 2006;Pakkasmaa et al 2006;Wang et al 2006), contributing both environmental and additive genetic effects to variability in offspring phenotype. Most studies in salmonids have focused on the maternal effects of egg size on the viability, survival, growth, and size of embryos and postemergence fry (Bams 1967;Hutchings 1991;Fleming 1999, 2000).…”

“…Considerable additive genetic variance for development rate has been revealed through quantitative genetic studies (Smoker 1986;Beacham 1988;Hebert et al 1998), and heritability has been reported as high as 0.23 in steelhead trout, O. mykiss (McIntyre and Blanc 1972). Many studies have shown that variation in development rate and survival prior to hatch is also significantly influenced by maternal effects (McIntyre and Blanc 1972;Blanc and Poisson 1983;Smoker 1986;Brown et al 2006). Although a few experiments have revealed the role of single regulatory loci in development rate in some populations of fishes (Allendorf et al 1983;DiMichele and Powers 1991), the number and nature of genetic loci influencing variation in embryonic development rate in other populations has only recently been investigated.…”