Sample collection, preparation and tissue grinding: Fresh samples of animal tissue were collected, trimmed to approximately 50 100 mg of wet weight, snap-frozen in liquid nitrogen, and stored at 800C. The animals were man, dog, cat, mouse, cow, and horse, as well as fish and clams; see Table 1. Before DNA and/or RNA extraction, the tissues were transferred frozen to a deep-well titer plate standing on a block of dry ice. Each well contained two 4-mm stainless steel balls (SPEX CertiPrep cat. no. 2150) and 500 microliters of buffer (Applied Biosystems nucleic acid purification lysis buffer). The plates were sealed with a plastic cover and subjected to grinding in the 2000 Geno/Grinder for 2 minutes at a setting of 1000 strokes per minute. After 30 minutes at 40 C, lysates were used for either gDNA extraction or total RNA extraction. Conditions were optimized for an Applied Biosystems 6700 automated nucleic acid (ANA) workstation, according to the manufacturers instructions. The final amount of tissue subjected to RNA and/or DNA extractions was between 10 and 20 mg. SPEXGENO 2010 高通量組織研磨機(jī)