Oxytocin/vasopressin and gonadotropin‐releasing hormone from cephalopods to vertebrates

Abstract

Recent advances in peptide search methods have revealed two peptide systems that have been conserved through metazoan evolution. Members of the oxytocin/vasopressin-superfamily have been identified from protostomian and deuterostomian animals, indicating that the oxytocin/vasopressin hormonal system represents one of the most ancient systems. In most protostomian animals, a single member of the superfamily shares oxytocin-like and vasopressin-like actions. Co-occurrence of two members has been discovered in modern cephalopods, octopus, and cuttlefish. We propose that cephalopods have developed two peptides in the molluscan evolutionary lineage like vertebrates have established two lineages in the oxytocin/vasopressin superfamily. The existence of gonadotropin-releasing hormone (GnRH) in protostomian animals was initially suggested by immunohistochemical analysis using chordate GnRH antibodies. A peptide with structural features similar to those of chordate GnRHs was originally isolated from octopus, and an identical peptide has been characterized from squid and cuttlefish. Novel forms of GnRH-like molecules from other molluscs, an annelid, arthropods, and nematodes demonstrate somewhat conserved structures at the N-terminal regions; but structures of the C-terminal regions critical to gonadotropin-releasing activity are diverse. These findings may be important for the study of the molecular evolution of GnRH in protostomian animals.

Regulation of feeding by Neuropeptide F in the desert locust, Schistocerca gregaria

“…Several invertebrate neuropeptides are similar and/or related to vertebrate peptides (Blumenthal, 2010;Lovejoy and Jahan, 2006;Minakata, 2010;Nässel and Wegener, 2011;Vanden Broeck, 2001;Van Loy et al, 2010). Vertebrate Neuropeptide Y (NPY) is involved in the regulation of diverse physiological processes, such as food intake, energy balance and learning (Benoit et al, 2008;Chee and Colmers, 2008;Hökfelt et al, 2008;Nguven et al, 2011;Redrobe et al, 1999).…”

Development of a time-resolved fluoroimmunoassay for octopus gonadotropin-releasing hormone

“…It has also been reported that levels of estradiol-17b and progesterone in the ovary of O. vulgaris increased with the gonadosomatic index and the morphological changes of the reproductive system [28]. Therefore, it has been suggested that oct-GnRH induces sexual maturation and oviposition in an endocrine fashion by regulating the sex steroids via oct-GnRHR [12,29]. On the basis of this hypothesis, the oct-GnRH levels in the CNS are predicted to increase in parallel with gonadal maturation.…”

Insect omics research coming of age1This review is part of a virtual symposium on recent advances in understanding a variety of complex regulatory processes in insect physiology and endocrinology, including development, metabolism, cold hardiness, food intake and digestion, and diuresis, through the use of omics technologies in the postgenomic era.

“…For example, neuropeptides belonging to the oxytocinvasopressin family not only occur in vertebrates but also in (Minakata 2010). These neuropeptides likely arose prior to the divergence of the Protostomia and Deuterostomia.…”