Two peptide transmitters co-packaged in a single neurosecretory vesicle.
Numerous neurosecretory cells are known to secrete more than one peptide, in both vertebrates and invertebrates. These co-expressed neuropeptides often originate from differential cleavage of a single large precursor, and are then usually sorted in the regulated pathway into different secretory vesicle classes to allow separable release dynamics. Here, we use immuno-gold electron microscopy to show that two very different neuropeptides (the nonapeptide crustacean cardioactive peptide (CCAP) and the 30 kDa heterodimeric bursicon) are co-packaged within the same dense core vesicles in neurosecretory neurons in the abdominal ganglia of Periplaneta americana. We suggest that this co-packaging serves a physiological function in which CCAP accelerates the distribution of bursicon to the epidermis after ecdysis to regulate sclerotization of the newly formed cuticle.
Department of Biological Sciences, Vanderbilt University, Nashville, TN 37235, USA.
Elvin A
EA
Woodruff
Kendal
K
Broadie
Hans-Willi
HW
Honegger
D000818:Animals; D017952:Ganglia, Invertebrate / Q000378:metabolism* / Q000648:ultrastructure; D007447:Invertebrate Hormones / Q000378:metabolism*; D007814:Larva / Q000378:metabolism / Q000648:ultrastructure; D016253:Microscopy, Immunoelectron; D009474:Neurons / Q000378:metabolism / Q000648:ultrastructure; D009479:Neuropeptides / Q000378:metabolism*; D010526:Periplaneta / Q000378:metabolism* / Q000648:ultrastructure; D022142:Secretory Vesicles / Q000378:metabolism* / Q000648:ultrastructure
D007447:Invertebrate Hormones; D009479:Neuropeptides; C058620:crustacean cardioactive peptide; C002295:bursicon