Expression profiles of genes coding for the antimicrobial peptides
(AMPs) Litsty PEN3 and lysozyme (GenBank accession numbers
AY351655 and CV699332, respectively) were analyzed by qPCR to examine
the general pattern of expression during the course of probiotic
candidate administration. During the third in vivo experiment 20 animals
were sampled from each tank at day 9 (around metamorphosis)
and 10 animals at day 19 (at the end of the larval rearing). Total RNA
was extracted using RNeasy columns (Qiagen) according to the
manufacturer's instructions. RNA quantity, purity and integrity were
verified spectrophotometrically (A260/A280) and by electrophoresis on
1% agarose gels. Quantitative PCRwas performed on an ABI 7300 system
as previously described (Labreuche et al., 2009). Amplification efficiencies
for all qPCR primers were determined according to Pfaffl (2001)
and the specificity of the PCR amplification verified from the melting
curve. Each run included the cDNA control, negative controls (total
RNA treated with DNase I), and blank controls (water). The relative
mRNA expression levels were determined using the two standard