Co-option and adaptation of novel gene duplications for pheromone activity in a dusky salamander.

Mechanisms of action and co-optive evolution for hypervariable courtship pheromones in plethodontid salamanders.

“…Chemical analysis of the mental gland has principally focused on two species, Ocoee's salamander (Demosgnathes ocoee) and the red-legged salamander (Plethodon shermani), as models of scratching and olfactory delivery systems, respectively [69,88].…”

“…Combined DNA sequencing and mass spectral proteomics efforts revealed that many of these proteins are products of gene co-option: gene duplication followed by mutation to drive neofunctionalization. In particular, many hormones (insulin, glucagon, insulin-like growth factor, leptin) were targets of gene co-option in D. ocoee and may adjust female physiology during courtship [88,89]. One protein, sodefrin precursor-like factor (SPF),…”

“…Dibasic cleavage sites consist of any combination of adjacent Lys or Arg residues and are often used to cleave and process peptide or protein hormones such as insulin, as well as several D. ocoee pheromones [88]. However, NPP may undergo additional N-terminal processing: several amino acids beyond the predicted signal peptide cleavage site were not detected and several NPP peptides were identified with sequences missing 2-11 amino acids at the N-terminus ( Figure 44).…”