EPIGENETIC REGULATION OF MUSCLE GROWTH BY PHOTOPERIOD IN ATLANTIC COD (Gadus morhua)

摘要

The use of continuous illumination has been a standard practice in Atlantic cod {Gadus morhua) farming. It is remarkable that a short term continuous light exposure during early juvenile stages can have a large impact on harvest size of nearly three years later (Imsland et al., 2007). The molecular mechanisms underlying this light-induced plasticity of muscle growth are hitherto unknown but it is likely that epigenetic regulation plays a critical role in this process. DNA methylation by DNA methyltransferases (DNMTs) and histone modifications by mixed lineage leukemias (MLLs) are two ofthe main epigenetic marking systems that play a critical role in regulating gene expression (Jenuwein & Allis, 2001; Palacios & Puri, 2006). In the present study, wehave investigated how photoperiod affects the expression of these two key gene families and their possible involvement in the epigenetic regulation of muscle growth in Atlantic cod.