Immunohistochemical studies of the carbonic anhydrase isozymes in the bovine placenta

Two different pathways for protein secretion are described for epithelial cells of rat coagulating gland and dorsal prostate: the classical merocrine and the alternative apocrine release mode. Apocrine-secreted proteins are synthesized on cytoplasmic polyribosomes and are subsequently exported in protrusions on the apical cell surface (aposomes). In this article we report the identification and purification to homogeneity of a 29-kD protein from the secretion of rat coagulating gland. N-terminal amino acid sequence analyses revealed 100% identity to rat brain carbonic anhydrase II (CAH II). In addition, the 29-kD protein showed CAH enzyme activity. On Western blot analysis, a polyclonal anti-CAH II antibody raised in rabbit reacted specifically with the rat and human but not bovine CAH II isoforms. Immunohistochemical studies on rat coagulating gland showed strong labeling for CAH II protein in aposomes. Immunoelectron microscopy confined CAH II protein to the cytoplasm and aposomes, whereas no staining was visible in the compartments of the classical merocrine route, the endoplasmic reticulum and Golgi apparatus. The resident cytoplasmic protein lactate dehydrogenase, however, was not found in the secretion. Taken together, the morphological and biochemical data clearly indicate that cytoplasmic CAH II from rat coagulating gland is specifically selected and then secreted via the apocrine pathway.

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Histochemical and immunohistochemical studies of four proteins (S100-? protein, carbonic anhydrase III, enolase ?-subunit, and creatine kinase M-subunit) in rhabdomyosarcoma

Pediatric Surgery International ◽

10.1007/bf00177171 ◽

1995 ◽

Vol 10 (4) ◽

Author(s):

Hiroshi Akatsuka ◽

Yukio Ishiguro ◽

Takahiro Ito ◽

Kanefusa Kato

Keyword(s):

Creatine Kinase ◽

Carbonic Anhydrase ◽

S100 Protein ◽

Carbonic Anhydrase Iii ◽

Immunohistochemical Studies

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Silicon Substitution for Calcium in the Shell of the Fingernail Clam, Musculium Transversum Studied By X-Ray Analysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600002488 ◽

1980 ◽

Vol 38 ◽

pp. 560-561

Author(s):

Judith A. Murphy ◽

Anthony Paparo ◽

Richard Sparks

Keyword(s):

Carbonic Anhydrase ◽

River Water ◽

Food Chains ◽

Well Water ◽

Shell Formation ◽

X Ray ◽

Molluscan Shell ◽

Fingernail Clams

Fingernail clams (Muscu1ium transversum) are dominant bottom-dwelling animals in some waters of the midwest U.S. These organisms are key links in food chains leading from nutrients in water and mud to fish and ducks which are utilized by man. In the mid-1950’s, fingernail clams disappeared from a 100-mile section of the Illinois R., a tributary of the Mississippi R. Some factor(s) in the river and/or sediment currently prevent clams from recolonizing areas where they were formerly abundant. Recently, clams developed shell deformities and died without reproducing. The greatest mortality and highest incidence of shell deformities appeared in test chambers containing the highest proportion of river water to well water. The molluscan shell consists of CaCO3, and the tissue concerned in its secretion is the mantle. The source of the carbonate is probably from metabolic CO2 and the maintenance of ionized Ca concentration in the mantle is controlled by carbonic anhydrase. The Ca is stored in extracellular concentric spherical granules(0.6-5.5μm) which represent a large amount of inertCa in the mantle. The purpose of this investigation was to examine the role of raw river water and well water on shell formation in the fingernail clam.

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