Postecdysial Changes in the Protein and Glycoprotein Composition of the Cuticle of the Blue Crab Callinectes sapidus

Shafer, Thomas H.; Roer, Robert D.; Miller, Charles G.; Dillaman, Richard M.

doi:10.2307/1548901

Cited by 24 publications

(21 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The C. sapidus glycoprotein material previously studied (Shafer et al, 1994(Shafer et al, , 1995Coblentz et al, 1998) was purified from total soluble protein extracts of cuticle from crabs killed at ecdysis. A jacalin lectin affinity column was used to separate glycoproteins with O-linked carbohydrates, which were then separated on the basis of size using a gel filtration column (Fig.·1).…”

Section: Discussionmentioning

confidence: 99%

“…Protease inhibitors were not included since no protease activity has been detected in extracts prepared in this manner (Shafer et al, 1994). Insoluble material was removed by centrifugation for 5·min at room temperature, and the supernatant dialyzed (MWCO 2000) against 50·mmol·l -1 ammonium bicarbonate for 48·h at 4°C.…”

Section: Glycoprotein and Mineralization In Blue Crabmentioning

confidence: 99%

“…A set of modifications of extracellular substances in the dorsal cuticle of C. sapidus termed the post-ecdysial cuticle alteration, or PECA, occurs immediately following ecdysis, in synchrony with a measured increase in the potential for calcite nucleation (Shafer et al, 1994(Shafer et al, , 1995. Specific changes include the loss of major protein bands at 66·kDa and 79·kDa in the first few hours post-ecydsis.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Purification of a soluble glycoprotein from the uncalcified ecdysial cuticle of the blue crabCallinectes sapidusand its possible role in initial mineralization

Tweedie

Coblentz

Shafer

2004

Journal of Experimental Biology

Self Cite

View full text Add to dashboard Cite

A heavily glycosylated soluble protein was purified using a combination of lectin affinity and size exclusion chromatography from a soluble extract of uncalcified dorsal cuticle of blue crab Callinectes sapidus removed at ecdysis. Similarities in apparent molecular mass and carbohydrate composition suggest that this protein is the same species previously shown to disappear from soluble extracts coincidentally with the onset of mineral deposition in the newly exposed post-molt cuticle. The amino acid sequence of the N-terminal portion of the core polypeptide was determined and polyclonal antibodies were raised against both the purified glycoprotein and the peptide. Immunoblots of unfractionated soluble extracts taken at various times post-molt illustrated that the antipeptide antibody recognized several polypeptides with electrophoretic mobilities that differ from the purified glycoprotein. These bands may be deglycosylation products which would not have been purified due to different lectin affinity or size. Immunohistochemical analysis indicated uniform protein distribution in the exocuticle at ecdysis, but decreased antibody binding at the interprismatic septa by 2·h post-molt. The location of the protein is therefore the negative image of the calcification pattern in the exocuticle and provides a spatial pattern to correlate with the previously reported temporal events. This strengthens the hypothesis that the glycoprotein under investigation is an inhibitor of calcite nucleation or of initial amorphous calcium carbonate accumulation.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Glycoprotein and Mineralization In Blue Crabmentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Purification of a soluble glycoprotein from the uncalcified ecdysial cuticle of the blue crabCallinectes sapidusand its possible role in initial mineralization

Tweedie

Coblentz

Shafer

2004

Journal of Experimental Biology

Self Cite

View full text Add to dashboard Cite

show abstract

“…It is not clear for which organisms this is true and it was certainly not seen in Callinectes sapidus. While there have been several recent studies of the carbohydrate composi- tion of calcified cuticle proteins (Marlow et al, 1994;Shafer et al, 1994Shafer et al, , 1995, there have been no studies to date that have examined the carbohydrate fraction of the arthrodial membrane. Since Anderson (1998Anderson ( , 1999 has observed very little overlap in protein distribution between the two types of cuticle, there is no reason to assume that there should be many similarities between the carbohydrate moieties.…”

Section: Discussionmentioning

confidence: 99%

Formation of the arthrodial membrane in the blue crab, Callinectes sapidus

Williams

Dillaman

Elliott

2003

Journal of Morphology

View full text Add to dashboard Cite

In this study the pattern of arthrodial membrane deposition in Callinectes sapidus was determined by histological and ultrastructural examination of tissues from the carpus joint of the cheliped collected during premolt, ecdysis, postmolt, and intermolt. Apolysis in the arthrodial membrane occurs at stage D(0) and is synchronous with apolysis of the calcified cuticle. Epicuticle formation begins at early stage D(1) and is completed in late stage D(1). Procuticle deposition starts at D(2) and continues until ecdysis. Numerous cytoplasmic extensions occur throughout the lamellae. Component fibers of the arthrodial membrane are intimately associated with dense plaques on the apical membrane of the underlying hypodermal cells, suggesting a site for fiber polymerization. Deposition of the arthrodial membrane continues after ecdysis, with most of the cuticle thickening occurring during stage C. When stained with PAS and counterstained with hematoxylin, a difference can be discerned between preecdysial and postecdysial procuticle of the arthrodial membrane, a distinction not made in previous studies. The boundary between the arthrodial membrane and calcified cuticle is thicker than either of the two layers and the layers overlap rather than butting up against one another. This pattern suggests that underlying hypodermal cells have to produce multiple types of cuticle over the molt cycle. A summary of the various molting patterns in C. sapidus suggests that the control of these diverse events may prove to be complex.

show abstract

“…Marlowe et al (1994) demonstrated the changes in the sugar moieties within the cuticle histologically, using labeled lectins. Shafer et al (1994Shafer et al ( , 1995 characterized the change in sugar moieties on individual glycoproteins and demonstrated that these changes coincided with the alteration of the cuticle's ability to nucleate mineral deposition.…”

Section: Introductionmentioning

confidence: 99%

The Initiation and Early Stages of Postmolt Mineralization in the Blue Crab, Callinectes sapidus

Roer¹,

Dillaman²

2018

Front. Mar. Sci.

Self Cite

View full text Add to dashboard Cite

Crabs are encased in a rigid exoskeleton or cuticle that is hardened by both protein crosslinking and calcification. In order to grow, the exoskeleton must be periodically molted. The two outermost layers of the exoskeleton of crabs are deposited prior to the molt, but remain uncalcified until the animal sheds its old exoskeleton. The inhibition of premolt calcification and initiation of postmolt calcification are effected by biochemical changes in the organic matrix. In the 2 h after the molt, sugar moieties are enzymatically altered on cuticular glycoproteins by an N-acetylhexosaminidase secreted by the underlying epithelium. These alterations appear to unmask nucleation sites that allow calcification to commence. The initial deposition of mineral is in the form of amorphous calcium carbonate (ACC). As postmolt calcification continues and the principal layer (endocuticle) is deposited and mineralized, the ACC is largely converted to or overgrown by calcite. Prior to the onset of ACC deposition, silicon has been detected in those areas of the exoskeleton that are about to undergo mineralization. As calcification proceeds, silicon is no longer detected. It is hypothesized that silicon is involved in the stabilization of ACC by destabilizing the crystal lattice of calcite before it undergoes the transition to or is overgrown by crystalline calcite.

show abstract

Postecdysial Changes in the Protein and Glycoprotein Composition of the Cuticle of the Blue Crab Callinectes sapidus

Cited by 24 publications

References 0 publications

Purification of a soluble glycoprotein from the uncalcified ecdysial cuticle of the blue crabCallinectes sapidusand its possible role in initial mineralization

Purification of a soluble glycoprotein from the uncalcified ecdysial cuticle of the blue crabCallinectes sapidusand its possible role in initial mineralization

Formation of the arthrodial membrane in the blue crab, Callinectes sapidus

The Initiation and Early Stages of Postmolt Mineralization in the Blue Crab, Callinectes sapidus

Contact Info

Product

Resources

About