Summary of experimental design. a Gills from two oyster families characterized by high (white circles) or low survival (hatched circles) of a 1 h, 43°C heat shock were collected before and at 1, 3, 6, and 24 h after a non-lethal heat shock (40°C, 1 h) in an experiment that was repeated three times to yield 60 samples. Each circle represents a sample that contained gill of three oysters. b One sample of cy3-labeled antisense RNA was hybridized to a single microarray slide (eg, a single-color microarray experiment). Slides were hybridized in batches of ten, as shown. c A subset of ESTs was studied using real-time quantitative polymerase chain reaction (RT-QPCR). The original samples of total RNA were used as template. Samples collected after 3 h recovery of heat shock were omitted