Bioluminescence in Polynoid Scale Worms (Annelida: Polynoidae)

Abstract

Bioluminescence is widespread throughout the phylum Annelida and occurs in terrestrial and marine lineages. Among marine taxa, bioluminescence has been documented in eight families and anecdotally reported in six additional families. Although new bioluminescent systems have been recently described in annelids, there are still many other families whose light emission mechanisms have not been sufficiently studied. Some of these include luminescent species belonging to the Polynoidae family, also known as scale worms, whose iterations of dorsal elytra (scales) have the ability to emit intense light when stimulated. Depending on the degree of stimulation, some polynoids can autotomize these luminous elytra and posterior segments, which could potentially give them an advantage in evading attacks by predators. It is believed that Polynoidae bioluminescence is associated with a membrane enzyme known as “polynoidin,” which was isolated during the early 1980s from Malmgrenia lunulata. However, the characterization and properties of this enzyme, as well as the chemical nature of its substrate or additional potential cofactors, have never been fully described and remain largely unknown. As such, this paper seeks to revisit previous research involving bioluminescence studies in Polynoidae, as well as the morphological, phylogenetic and ecological aspects related to this emission of light.

First Record of Bioluminescence in a Sipunculan Worm

“…According to some authors, the homogenate prepared from the luminous scales was capable of emitting light through the addition of various reagents, such as sodium dithionite (Herrera et al, 1974), ferrous ions (Lecuyer and Arrio, 1975), xanthinexanthine oxidase system, and Fenton reaction (Nicolas et al, 1979). The isolated 66 kDa photoprotein was named polynoidin, but there is no additional information available on the chemical studies of bioluminescence in Harmothoe, nor any proposal for a chemical structure for its luciferin or methodologies described to isolate it (Nicolas et al, 1982;Shimomura, 2006;Moraes et al, 2021).…”

“…There is no single habitat in which marine annelids are particularly prone to displaying bioluminescence nor a particular body region that produces light. Some examples of bioluminescent annelids include the tube-dwelling chaetopterids (Nicol, 1952b(Nicol, ,c,a, 1957Mirza et al, 2020), epifaunal taxa such as polynoid scale worms (Nicol, 1954;Herrera, 1979;Plyuscheva and Martin, 2009;Moraes et al, 2021), and pelagic forms such as tomopterids (Dales, 1971;Gouveneaux et al, 2017). Additionally, there is a wide variety of wavelengths of emitted light, from yellow to blue (Verdes and Gruber, 2017).…”

Towards the identification of the molecular toolkit involved in scale worm bioluminescence (Polinoidae, Annelida)

“…Among these, there are important differences in the chemistry of the bioluminescence systems used by marine and terrestrial taxa, which suggests the independent origin of bioluminescence [14–18]. Polynoids, also known as scale worms, are a group of marine annelids with several bioluminescent species reported, including members of the genera Gattyana , Malmgrenia , Polynoe and Harmothoe [11, 16, 19–21] and possibly Neopolynoe [10]. Polynoids are characterized by a series of paired structures denominated scales or elytra which are arranged in two rows covering entirely or partially the length of the dorsum [22] (Fig.…”

Investigating the diversity of bioluminescent marine worm Polycirrus (Annelida), with description of three new species from the Western Pacific

“…Despite its occurrence, there is still much that is unknown about bioluminescence in polychaetes, including how it evolved and what it means ecologically. More research is needed to better understand this phenomenon, and to do this, we need to accumulate more examples of bioluminescent polychaetes [3,5,[7][8][9][10][11][12].…”