spongin


Also found in: Dictionary, Medical, Wikipedia.
Related to spongin: osculum, spongocoel

spongin

[′spən·jən]
(biochemistry)
A scleroprotein, occurring as the principal component of skeletal fibers in many sponges.
References in periodicals archive ?
In addition to necrotized sponges, remnants of the supportive skeletons (spongin) of basket sponges were observed lying on the sea floor in the trawl path.
Insights into early extracellular matrix evolution: spongin short chain collagen-related proteins are homologous to basement membrane type IV collagens and form a novel family widely distributed in invertebrates.
Despite the sharp, needlelike structure of many spicules and the relative indigestibility of spongin, these two traits have recently been described as serving little or no antipredator function in Caribbean sponges (Pawlik et at., 1995; Chanas and Pawlik, 1995, 1996; Waddell and Pawlik, 2000a, b).
The sponge is grey or olive brown, and its texture is firm due to a welldeveloped anisotropic reticulate network of primary spongin that is cored by paucispicule to multispicule tracts of oxeas 80-100 [micro]m long by 1 [micro]m wide.
Although spicules are formed in a space surrounded by a membrane, finished spicules are surrounded by discontinuous cytoplasm or by spongin microfilaments only (Fig.
The strands tended to be straight, with only slight bends and turns where they coursed around the spongin skeleton (e.g., [ILLUSTRATION FOR FIGURE 2B OMITTED]), and there were no cross-connections between strands.
Furthermore, the structure of the spongin fibers of Agelas (De Vos et al., 1991), which are unique among the Demospongiae, is an important difference between Agelas and Astrosclera.