Gene expression of secretory proteins in the nuptial pads of three Lithobates species (Anura: Ranidae)

Abstract Many amphibian species possess male-specific secretory breeding glands. In anurans, such specialized glands are often present as nuptial pads at the first digit of hand, which pressed against female during amplexus. However, role pad secretions remains largely unknown. Here, we investigate inner morphology well RNA expression patterns several Central American Lithobates (Ranidae). As shown for other species, composed large mucus glands, excreting proteinaceous content to surface. Whole-transcriptome sequencing revealed that one most highly expressed transcripts encoding proteins in sodefrin precursor-like factor (SPF) proteins, known have a pheromone function multiple species. The two however, lack high SPF but express whose roles remain Several these all samples, suggesting direct courtship or maintenance/development