Genes enriched in secondary alveolar septae of neonatal lung tissue

The tips of secondary alveolar septae in day 6 neonatal mouse lung tissue were isolated using laser capture microscopy. RNA was isolated from pooled secondary alveolar tips and also from pooled neonatal day 6 whole lung tissue. The isolated RNAs were then amplified in parallel. Gene array profiling of the two RNA samples was performed. Gene expression in the secondary alveolar septal tips was compared to gene expression in the whole lung tissue. In this way, the genes that are expressed in the tip of secondary alveolar septae were identified as well as the genes that are enriched in the alveolar septal tips versus in whole lung tissue. Keywords: Comparison of gene profiles in the tips of secondary alveolar septae versus in whole lung tissue of neonatal mice We performed an experiment in which we used laser capture microscopy to collect 10,000 secondary alveolar tips from frozen sections of lung tissue obtained from many different day 6 neonatal mice obtained from different litters. In the same experiment, we also isolated RNA from pooled day 6 neonate whole lung tissue. The isolated RNAs were amplified in parallel and then hybridized to microarrays in parallel in order to profile and compare gene expression in the two samples. The entire experiment was performed twice with tissue from different litters. In addition, the amplified RNAs were hybridized to two different microarrays, at different times.