title: GSM1181372: AF; Bos taurus; RNA-Seq
library_construction_protocol: On day 200 (d200), bovine embryos (gestation period 280 days) were collected into sterile physiological saline immediately after removal from the reproductive tract of slaughtered cows at a local abattoir. These tissues were snap-frozen in liquid nitrogen and stored at -80°C until use. RNA was harvested using Trizol reagent. RNA libraries were prepared for sequencing using standard Illumina protocols. Low molecular weight RNAs were separated by 15% polyacrylamide gel electrophoresis (PAGE), and RNA molecules in the range of 18–30nt were enriched and ligated with proprietary adapters to the 5' and 3' termini. A reverse transcription reaction followed by low-cycle PCR was performed to obtain sufficient product for Solexa technology.