scholarly journals Characterization and expression of plasma membrane Ca2+ ATPase (PMCA3) in the crayfish Procambarus clarkii antennal gland during molting

2004 ◽  
Vol 207 (17) ◽  
pp. 2991-3002 ◽  
Author(s):  
Y. Gao



2009 ◽  
Vol 23 (S1) ◽  
Author(s):  
Yang Gao ◽  
Yongping Gao ◽  
Michele Wheatly ◽  
Carissa Krane


1999 ◽  
Vol 276 (2) ◽  
pp. R566-R574 ◽  
Author(s):  
Michele G. Wheatly ◽  
Robert C. Pence ◽  
Jennifer R. Weil

ATP-dependent Ca2+ uptake was determined into inside-out basolateral membrane vesicles (BLMV) from intermolt crayfish ( Procambarus clarkii) Ca2+-transporting epithelia: gill, hepatopancreas (liver), and antennal gland (kidney). Extravesicular (EV) ATP (5 mM) increased45Ca2+uptake (free Ca2+ 5 μM) by fivefold but was abolished by pretreatment with either vanadate or the ionophore A-23187. Addition of A-23187 to Ca2+-loaded vesicles produced 70% efflux. The saturable carrier exhibited a K m for Ca2+ of 0.11–0.27 μM and maximal influx of 20–123 pmol ⋅ mg−1 ⋅ min−1. The K m for ATP was 0.01–0.04 mM. The temperature coefficient ranged from 1.43 to 2.06. EGTA treatment of hepatopancreas and antennal gland vesicles decreased45Ca2+uptake by 50–90%; uptake was restorable by calmodulin. However, in gill,45Ca2+uptake was unaffected by EGTA treatment and calmodulin decreased uptake in both EGTA-treated and untreated vesicles. Addition of EV Na+ (5 mM) increased ATP-dependent Ca2+ uptake into hepatopancreas and antennal gland BLMV by 60%; in hepatopancreas BLMV, this increase was inhibitable by ouabain. However, ATP-dependent Ca2+ uptake in gill vesicles was Na+ independent. The relative role of each epithelium in whole animal Ca2+ homeostasis has been interpreted based on in vitro characteristics.



1998 ◽  
Vol 274 (3) ◽  
pp. R725-R734
Author(s):  
Michele G. Wheatly ◽  
Jennifer R. Weil ◽  
Phyllis B. Douglas

Procedures were developed to isolate basolateral membrane vesicles (BLMV) from gill, hepatopancreas, and antennal gland of intermolt freshwater crayfish, Procambarus clarkii. Individual procedures involved a discontinuous sucrose gradient (gill), a 65% sucrose cushion (hepatopancreas), or differential centrifugation (antennal gland). BLMV were visualized, characterized (37°C), and tested for osmotic reactivity with a view to using them for Ca2+ uptake studies. Mean diameters of BLMV were 159 nm (gill), 363 nm (hepatopancreas), and 226 nm (antennal gland). Enrichments of basolateral membranes and mitochondria in BLMV were, respectively, 18- and 1.7-fold for gill, 9- and 0.4-fold for hepatopancreas, and 10- and 1-fold for antennal gland. Apical contamination was negligible in BLMV. Percentages of resealing of vesicles as inside out, right side out, or leaky/sheets were 17:27:56% (gill), 14:26:60% (hepatopancreas), and 21:39:40% (antennal gland). Vesicles exhibited osmotic reactivity, as indicated by a linear relationship between vesicular45Ca2+uptake and osmolality. Nonspecific45Ca2+binding was 20% in gill, 39% in hepatopancreas, and 31% in antennal gland. Data were compared with published values for marine crustaceans.



Author(s):  
E. Keyhani

The matrix of biological membranes consists of a lipid bilayer into which proteins or protein aggregates are intercalated. Freeze-fracture techni- ques permit these proteins, perhaps in association with lipids, to be visualized in the hydrophobic regions of the membrane. Thus, numerous intramembrane particles (IMP) have been found on the fracture faces of membranes from a wide variety of cells (1-3). A recognized property of IMP is their tendency to form aggregates in response to changes in experi- mental conditions (4,5), perhaps as a result of translational diffusion through the viscous plane of the membrane. The purpose of this communica- tion is to describe the distribution and size of IMP in the plasma membrane of yeast (Candida utilis).Yeast cells (ATCC 8205) were grown in synthetic medium (6), and then harvested after 16 hours of culture, and washed twice in distilled water. Cell pellets were suspended in growth medium supplemented with 30% glycerol and incubated for 30 minutes at 0°C, centrifuged, and prepared for freeze-fracture, as described earlier (2,3).



Author(s):  
Hilton H. Mollenhauer ◽  
W. Evans

The pellicular structure of Euglena gracilis consists of a series of relatively rigid strips (Fig. 1) composed of ridges and grooves which are helically oriented along the cell and which fuse together into a common junction at either end of the cell. The strips are predominantly protein and consist in part of a series of fibers about 50 Å in diameter spaced about 85 Å apart and with a secondary periodicity of about 450 Å. Microtubules are also present below each strip (Fig. 1) and are often considered as part of the pellicular complex. In addition, there may be another fibrous component near the base of the pellicle which has not yet been very well defined.The pellicular complex lies underneath the plasma membrane and entirely within the cell (Fig. 1). Each strip of the complex forms an overlapping junction with the adjacent strip along one side of each groove (Fig. 1), in such a way that a certain amount of sideways movement is possible between one strip and the next.



Author(s):  
G. I. Kaye ◽  
J. D. Cole

For a number of years we have used an adaptation of Komnick's KSb(OH)6-OsO4 fixation method for the localization of sodium in tissues in order to study transporting epithelia under a number of different conditions. We have shown that in actively transporting rabbit gallbladder epithelium, large quantities of NaSb(OH)6 precipitate are found in the distended intercellular compartment, while localization of precipitate is confined to the inner side of the lateral plasma membrane in inactive gallbladder epithelium. A similar pattern of distribution of precipitate has been demonstrated in human and rabbit colon in active and inactive states and in the inactive colonic epithelium of hibernating frogs.



Author(s):  
T. G. Sarphie ◽  
C. R. Comer ◽  
D. J. Allen

Previous ultrastructural studies have characterized surface morphology during norma cell cycles in an attempt to associate specific changes with specific metabolic processes occurring within the cell. It is now known that during the synthetic ("S") stage of the cycle, when DNA and other nuclear components are synthesized, a cel undergoes a doubling in volume that is accompanied by an increase in surface area whereby its plasma membrane is elaborated into a variety of processes originally referred to as microvilli. In addition, changes in the normal distribution of glycoproteins and polysaccharides derived from cell surfaces have been reported as depreciating after cellular transformation by RNA or DNA viruses and have been associated with the state of growth, irregardless of the rate of proliferation. More specifically, examination of the surface carbohydrate content of synchronous KB cells were shown to be markedly reduced as the cell population approached division Comparison of hamster kidney fibroblasts inhibited by vinblastin sulfate while in metaphase with those not in metaphase demonstrated an appreciable decrease in surface carbohydrate in the former.



Author(s):  
B.K. Ghosh

Periplasm of bacteria is the space outside the permeability barrier of plasma membrane but enclosed by the cell wall. The contents of this special milieu exterior could be regulated by the plasma membrane from the internal, and by the cell wall from the external environment of the cell. Unlike the gram-negative organism, the presence of this space in gram-positive bacteria is still controversial because it cannot be clearly demonstrated. We have shown the importance of some periplasmic bodies in the secretion of penicillinase from Bacillus licheniformis.In negatively stained specimens prepared by a modified technique (Figs. 1 and 2), periplasmic space (PS) contained two kinds of structures: (i) fibrils (F, 100 Å) running perpendicular to the cell wall from the protoplast and (ii) an array of vesicles of various sizes (V), which seem to have evaginated from the protoplast.



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