Identification of tick periviscerokinin, the first neurohormone of Ixodidae: Single cell analysis by means of MALDI-TOF/TOF mass spectrometry

• Published in: Biochemical and biophysical research communications Vol. 338; no. 4; pp. 1860 - 1864
• Main Authors: Neupert, Susanne, Predel, Reinhard, Russell, William K., Davies, Ronald, Pietrantonio, Patricia V., Nachman, Ronald J.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 30.12.2005
• Subjects: Amino Acid Sequence; analytical methods; Animals; Boophilus; Boophilus microplus; cells; Fluorescent Antibody Technique; immunohistochemistry; Insect Hormones - analysis; Ixodes; Ixodes ricinus; Ixodidae; Ixodidae - chemistry; kinins; MALDI-TOF/TOF mass spectrometry; mass spectrometry; neurohormones; neurons; Neuropeptide; neuropeptides; Neuropeptides - analysis; Neuropeptides - chemistry; Periviscerokinin; sequence homology; Single cell analysis; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Tick; ticks; MALDI-TOF/TOF mass spectrometry; Ixodes; Periviscerokinin; Tick; Neuropeptide; Single cell analysis; Boophilus
• ISSN: 0006-291X; 1090-2104; 1090-2104
• DOI: 10.1016/j.bbrc.2005.10.165

The first peptidergic neurohormone from the ticks Ixodes ricinus and Boophilus microplus has been identified by using a combination of immunocytochemistry and mass spectrometric analysis of single cells. The novel peptide (Ixori-PVK, PALIPFPRV-NH 2) shows a high sequence homology with members of the insect periviscerokinin/CAP2 b peptides that in insects are involved in the regulation of water balance. The function of this peptide in ticks is still unknown, but these pests consume large amounts of blood in a single blood meal which is a challenge for the regulation of diuretic processes. Thus, the novel peptide may be involved in one of the key physiological processes in ticks. High energy collision-induced dissociation was successfully used to distinguish between Leu/Ile ambiguities in single cell preparations. This is the first successful de novo sequencing of a peptide from single cell preparations of arthropods.