• Ocean and Polar Research
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• v.23 no.4
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• pp.419-424
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• 2001

The Antarctic clam Laternula elliptica, is one of the most representative benthic invertebrates in the Antarctic nearshore waters. Endemic to the Antarctic, L. elliptica is widely distributed around the Antarctica occurring as dense patches in shallow sheltered areas and exhibits high biomass. Despite its apparent ecological importance, L. elliptica has rarely been studied until recently probably due to difficulties in sampling in the ice-impacted waters. Recent studies have revealed various aspects of its ecology and physiology. In this review, some physiological and ecological characteristics of this species are discussed in relation to some prevailing features of its habitat environment, in particular physical instability of habitat substrates and extreme seasonality of food availability.

• The Korean Journal of Malacology
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• v.18 no.1
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• pp.15-21
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• 2002

The kidney of bivalve mollusks often contains remarkably high concentrations of both essential and non-essential metals and perform regulating and detoxicating activities. The kidney has also been proposed as a biological indicator for radioactive as well as for stable metals in the sea. The present study of the Antarctic clam, Laternula elliptica, concerns the functional morphology of the kidney epithelium, which contains highly accumulated heavy metals. The immunohistochemical and ultrastructural study was undertaken in order to find out the localization of metallothionein and heavy metals accumulated in the kidney of Laternula elliptica. In the immunohistochemical investigation, an intense metallothionein immunostaining reaction was found in the epithelial cells of the kidney of Laternula elliptica. Transmission electron microscopy showed that the epithelial cells contained numerous electron-dense inclusion bodies which were considered to be accumulated heavy metals.

• The Korean Journal of Malacology
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• v.10 no.2
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• pp.41-46
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• 1994

The Antarctic soft-shelled clam, Laternula elliptica is widely distributed in shallow waters around the Antarctic Continent and islands. This bivalve species occurs in densepatches particularly in sheltered but frequently ice-impacted areas. This species mostly occurs at atound 20-30 m depth and is rarely found at depths shallower than 5 m where ice abrasion by drifting or grounded icebergs is severe. It burrows deep into sedimint(frequently >50 cm), which seems to be primarily a means for avoiding ice impacts. A pair of stout and highly extendable siphons appear to be a morphological reature to feed in the ice-scoured substrates while staying deep in the sedimint. As one of the largest bivalves in the Antarctic waters, L. elliptica appears to grow rapidly, reaching to a shell length of approximately 100 mm in 12 or 13 years. L. elliptica feeds sctively during summer when food is sufficiently provided, implying that food may be the most inportant fator regulating the growth. Seasonal variations in food availability, and metabolic process in starvation condition possibly during winter, however, are yet to be further investigated.

• Proceedings of the Korean Environmental Health Society Conference
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• 2004.06a
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• pp.87-91
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• 2004

Immunohistochemical and ultrastructural experiments were conducted to find out heavy metal accumulation in some selected organs such as the kidney, the hepatopancreas, and the gills of the Antarctic Clam Laternula elliptica According to the immunohistochemical study the subject organs of the clam showed reactions indicating the presence of MT(metallothionein), a metal-binding protein involved in metal detoxifying process. Examination under the transmission electron microscope also revealed that other ligands(e.g. metal-rich granules in the kidney) may play a role in metal accumulating and detoxifying process in L. elliptica. In the artificial exposure of the clam to Cd, it showed immediate subcellular responses, suggesting that this species can be used as rapid and efficient bioindicators for Cd exposure in natural environment.

• Ocean and Polar Research
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• v.23 no.4
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• pp.337-345
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• 2001

A Cd-binding protein was identified in the renal cytosol of the Antarctic clam Laternula elliptica which naturally contains high concentrations of Cd. The Cd-binding protein showed similar characteristics of metallothionein (MT) in molecular weight (about 10-12 kDa) and low spectral absorbance at 280 nm with relatively high absorbance at 254nm. Results of immuno-histochemical staining suggested that the MT-like Cd-binding protein was mainly located in the epithelial cells of the kidney. The MT-like protein was a major ligand of cytosolic Cd as shown in the elution profiles of chromatography and may play an important role in Cd sequestration and accumulation in L. elliptica kidney. A considerable amount of Cd was also found to be associated with particulate fraction, indicating the sequestration to particulate fraction is as important as binding to the cytosolic MT-like protein in Cd accumulation in the kidney.

• Proceedings of the Malacological Society of Korea Conference
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• 2002.05a
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• pp.5-5
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• 2002

• Proceedings of the Korean Environmental Health Society Conference
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• 2004.12a
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• pp.63-68
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• 2004

Immunohistochemical and ultrastructural experiments were conducted to find out heavy metal accumulation in some selected organs such as the kidney, the digestive gland, and the gill of the Antarctic clam Laternula elliptica and R. philippinarum. According to the immunohistochemical study the subject organs of the clam showed reactions indicating the presence of MT (metallothionein), a metal-binding protein involved in metal detoxifying process. Examination under the transmission electron microscope also revealed that other ligands may play a role in metal accumulating and detoxifying process in L. elliptica and R. philippinarum. In the artificial exposure of the clam to Cd, the clams showed immediate subcellular responses. The level of the anti-MT reactions became higher in the proportion to the degree of pollution of their habitat and to the period of Cd exposure. These suggest that the two species can be used as efficient biomarkers for Cd exposure in the natural environment.

• Proceedings of the Malacological Society of Korea Conference
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• 2003.11a
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• pp.38-38
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• 2003

• Proceedings of the Zoological Society Korea Conference
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• 2001.04a
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• pp.59.2-59
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• 2001

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