| Full text | |
| Author(s): |
Silva Firmino, Kelly Cristina
[1]
;
Faleiros, Rogerio Oliveira
[2]
;
Masui, Douglas Chodi
[1, 2]
;
McNamara, John Campbell
[2]
;
Melo Furriel, Rosa Prazeres
[1]
Total Authors: 5
|
| Affiliation: | [1] Univ Sao Paulo, Dept Quim, Fac Filosofia Ciencias & Letras Ribeirao Preto, BR-14040901 Sao Paulo - Brazil
[2] Univ Sao Paulo, Dept Biol, Fac Filosofia Ciencias & Letras Ribeirao Preto, BR-14040901 Sao Paulo - Brazil
Total Affiliations: 2
|
| Document type: | Journal article |
| Source: | COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY B-BIOCHEMISTRY & MOLECULAR BIOLOGY; v. 160, n. 1, p. 24-31, SEP 2011. |
| Web of Science Citations: | 14 |
| Abstract | |
To better understand the biochemical mechanisms underlying anisosmotic extracellular regulation in the freshwater Brachyura, we kinetically characterized the V-ATPase from the posterior gills of Dilocarcinus pagei, acclimated for 10 days to salinities up to 21%.. Specific activity was highest in fresh water (26.5 +/- 2.1 U mg(-1)), decreasing in 5 parts per thousand to 21 parts per thousand, attaining 3-fold less at 15 parts per thousand. Apparent affinities for ATP and Mg(2+) respectively increased 3.2- and 2-fold at 10 parts per thousand, suggesting expression of different isoenzymes. In a 240-h time-course study of exposure to 21%., maximum specific activity decreased 2.5- to 4-fold within 1 to 24 h while apparent affinities for ATP and Mg(2+) respectively increased by 12-fold within 24 h and 2.4-fold after 1 h, unchanged thereafter. K(I) for bafilomycin A(1) decreased 150-fold after 1 h, remaining constant up to 120 h. This is the first kinetic analysis of V-ATPase specific activity in crustacean gills during salinity acclimation. Our findings indicate active gill Cl(-) uptake by D. pagei in fresh water, and short- and long-term down-regulation of V-ATPase-driven ion uptake processes during salinity exposure, aiding in comprehension of the biochemical adaptations underpinning the establishment of the Brachyura in fresh water. (C) 2011 Elsevier Inc. All rights reserved. (AU) | |
| FAPESP's process: | 07/04870-9 - Adaptive physiological strategies in the Crustacea: the invasion of fresh water and the molecular and structural bases of osmoregulation |
| Grantee: | John Campbell McNamara |
| Support Opportunities: | Regular Research Grants |