Global gene expression during the photoinduction process.

The molecular mechanism of photoperiodic time measurement remains unknown in animals. Japanese quail is an excellent model for studying these phenomena because of their rapid and dramatic response to photoperiod. When quail are transferred from short to long day conditions, increase in plasma gonadotrophin (luteinising hormone: LH) can be observed by the end of the first long day and this phenomenon is called “first day release model”. To dissect the system dynamics and network structure regulating photoperiodism, we examined global gene expression using high-density oligonucleotide microarray for chicken (Affymetrix Chicken Genome Array). Keywords: time course The mediobasal hypothalamus (MBH) of quail was collected from 6 birds for each time point during the photoinduction process. Pooled total RNA from three MBHs was labelled and hybridized to each Affymetrix chicken genome array. Samples were analyzed in duplicate set of array (two biological replicate).