Invertebrate neuropeptide hormones

Abstract

The development of a long-term research program on the neurosecretory hormones of arthropods is described. The purification and full characterization of the first invertebrate neurohormones, the red pigment-concentrating hormone (RPCH) and the distal retinal pigment hormone (DRPH) demonstrated that they are peptides, an octapeptide and an octadecapeptide, respectively. Physiological function studies with the pure hormones and their synthetic preparations showed that the RPCH acts as a general pigment-concentrating hormone (PCH), and that the DRPH, in addition t o its light-adaptive function, also constitutes a general pigment-dispersing hormone (PDH). In the regulation of the coloradaptation of the animals, the two hormones act as antagonists. The chromatophorotropic activities are widely distributed within the arthropod neuroendocrine systems. Purification of the pigment-concentrating activities from the locust corpora cardiaca lead t o the isolation and characterization of the first insect neurohormones, the adipokinetic hormones (AKH I and AKH 11). These two hormones, AKH I being a decapeptide and AKH I1 being an octapeptide, are close structural analogs to the crustacean PCH, demonstrating a common evolution of arthropod neurohormones. The hormones of this PCH-family all cross-react, but structure-function studies of the hormones show that quite different parts of their structure are involved in their binding t o the various receptors.

Invertebrate Gonadotropin-Releasing Hormone-Related Peptides and Their Receptors: An Update

“…Adipokinetic hormones have so far been shown to stimulate the fat body, resulting in lipid and carbohydrate mobilization into the hemolymph in insects and crustaceans. Furthermore, a homolog of AKH in the northern shrimp, Paudalus borealis , red pigment concentrating hormone, influenced the concentration of pigment chromatophore, causing its body color change ( 43 ). Notably, AKHs also showed a reduction in oocyte protein and carbohydrate content in the crickets, Gryllus bimaculatus , and a reduction in vitellogenin of oocytes in L. migratoria ( 44 ), indicating a regulatory role for AKHs in insect reproduction.…”

APGW/AKH Precursor from Rotifer Brachionus plicatilis and the DNA Loss Model Explain Evolutionary Trends of the Neuropeptide LWamide, APGWamide, RPCH, AKH, ACP, CRZ, and GnRH Families

“…Other neuropeptides that contain homologous amino acids at the carboxylic end of LWamide and APGWamide are named according to their physiological activity, including the red pigment-concentrating hormone (RPCH) and adipokinetic hormone (AKH) (Josefsson 1983 ). Both neuropeptides occur in monocopy, and their precursor consists of eight amino acids.…”

“…However, some AKHs can have nine to twelve amino acids (Martínez-Pérez et al 2007 ). Additionally, a phenylalanine residue is typically present in the fourth position from the N-terminal of both neuropeptides (Josefsson 1983 ; Gäde 2009 ; Gäde et al 2020 ). Another similarity between the members of the RPCH and AKH families is that they have a tryptophan residue and an amidated glycine in the C-terminus (Martínez-Pérez et al 2007 ).…”

ISOLATION AND SEQUENCE ANALYSIS OF A PIGMENT-DISPERSING HORMONE FROM EYESTALKS OF THE CRAB,CANCER MAGISTER

“…Until recently, knowledge of the primary structure of crustacean pigmentaryeffector hormones was restricted to two hormones (Kleinholz, 1985): red pigment concentrating hormone (RPCH), an octapeptide (Fernlund and Josefsson, 1972;Fernlund, 1974a, b), and light-adapting distal retinal pigment hormone (DRPH), an octadecapeptide, isolated from eyestalks of Pandalus borealis (Fernlund, 1971(Fernlund, , 1976(Fernlund, , 1977. The DRPH is one of the several forms of a molecule that acts both as a lightadapting hormone and chromatophorotropic pigment-dispersing hormone, PDH (Kleinholz, 1970(Kleinholz, , 1975Riehm and Rao, 1982;Josefsson, 1983).…”