Pyrokinin/PBAN-like peptides in the central nervous system of mosquitoes

The pyrokinin/pheromone biosynthesis activating neuropeptide (PBAN) family of peptides is characterized by a common C-terminal pentapeptide, FXPRLamide, which is required for diverse physiological functions in various insects. Polyclonal antisera against the C-terminus was utilized to determine the location of cell bodies and axons in the central nervous systems of larval and adult mosquitoes. Immunoreactive material was detected in three groups of neurons in the subesophageal ganglion of larvae and adults. The corpora cardiaca of both larvae and adults contained immunoreactivity indicating potential release into circulation. The adult and larval brains had at least one pair of immunoreactive neurons in the protocerebrum with the adult brain having additional immunoreactive neurons in the dorsal medial part of the protocerebrum. The ventral ganglia of both larvae and adults each contained one pair of neurons that sent their axons to a perisympathetic organ associated with each abdominal ganglion. These results indicate that the mosquito nervous system contains pyrokinin/PBAN-like peptides and that these peptides could be released into the hemolymph. The peptides in insects and mosquitoes are produced by two genes, capa and pk/pban. Utilizing PCR protocols, we demonstrate that products of the capa gene could be produced in the abdominal ventral ganglia and the products of the pk/pban gene could be produced in the subesophageal ganglion. Two receptors for pyrokinin peptides were differentially localized to various tissues

Pyrokinin/PBAN peptides in the central nervous system of mosquitoes (Diptera: Culicidae)

The pyrokinin/pheromone biosynthesis activating neuropeptide (PBAN) family of peptides in insects has been shown to have diverse physiological functions, including stimulation of pheromone biosynthesis, muscle contraction, melanization and acceleration of puparium formation. An active core of a 5-amino-acid C terminal sequence, FXPRLamide, required for physiological functions, characterizes this family of peptides. Immunocytochemical techniques were used to demonstrate the presence of pyrokinin/PBAN-like peptides in the central nervous system of adult and larval mosquitoes, Culicidae. The ventral nerve cord of Culicidae consists of the subesophageal ganglia (SEG), three thoracic ganglia and six or eight abdominal ganglia in larvae and adults respectively. Immunoassays with an anti-PBAN antibody and FITC labeled detection probe revealed three groups of peptide-producing cell bodies in the SEG. The peptide was also observed in axons originating in the SEG and terminating in the terminal abdominal ganglion (TAG). A pair of reactive cell bodies was detected in the first thoracic ganglion and all abdominal ganglia with the exception of the TAG. A neurohemal organ containing reactive peptide was associated with the pair of cell bodies in each abdominal ganglion. These results show that the mosquito nervous system contains pyrokinin/PBAN-like peptides and that these peptides likely are released into the hemolymph.</p

Pyrokinin/PBAN-like peptides in the central nervous system of mosquitoes

The pyrokinin/pheromone biosynthesis activating neuropeptide (PBAN) family of peptides is characterized by a common C-terminal pentapeptide, FXPRLamide, which is required for diverse physiological functions in various insects. Polyclonal antisera against the C-terminus was utilized to determine the location of cell bodies and axons in the central nervous systems of larval and adult mosquitoes. Immunoreactive material was detected in three groups of neurons in the subesophageal ganglion of larvae and adults. The corpora cardiaca of both larvae and adults contained immunoreactivity indicating potential release into circulation. The adult and larval brains had at least one pair of immunoreactive neurons in the protocerebrum with the adult brain having additional immunoreactive neurons in the dorsal medial part of the protocerebrum. The ventral ganglia of both larvae and adults each contained one pair of neurons that sent their axons to a perisympathetic organ associated with each abdominal ganglion. These results indicate that the mosquito nervous system contains pyrokinin/PBAN-like peptides and that these peptides could be released into the hemolymph. The peptides in insects and mosquitoes are produced by two genes, capa and pk/pban. Utilizing PCR protocols, we demonstrate that products of the capa gene could be produced in the abdominal ventral ganglia and the products of the pk/pban gene could be produced in the subesophageal ganglion. Two receptors for pyrokinin peptides were differentially localized to various tissues.This is a manuscript of an article from Cell and Tissue Research 356 (2014): 39, 10.1007/s00441-013-1782-8. Posted with permission.</p