Whole genome sequencing of C. elegans
N2 animals were harvested by chilling on ice, centrifugation at 950g for two minutes and washing several times with cold M9. Pellets consisting each of approximately 100µl of closely packed worms were flash frozen in liquid nitrogen and stored in -80°C.  The flash frozen worm pellets were ground to fine powder in liquid nitrogen. The grinding was performed either using mortar and pestle or using an electric drill with “Cellcrusher” drill-bit and “Cellcrusher” base held at liquid nitrogen temperatures. The grinding was done for several minutes, until reaching a fine powder. The powder was stored at -80°C. To get the DNA used for libraries construction, frozen pellets were subjected to lysis, salt precipitation and RNAse A treatment. After phenol/chloroform extraction DNA was precipitated using EtOH. After DNA fragmentation using Covaris the DNA was size selected (~500bp) using agaroze gel. Extracted from gel DNA fragments were subjected to end repair and ligation of Illumina sequencing compatible annealed adapter sequences. Ligation products were PCR amplified prior to sequencing.