Presence of an isoform of H+-pyrophosphatase located in the alveolar sacs of a scuticociliate parasite of turbot: physiological consequences

Mallo, N., Lamas, J., Defilipe, A.-P., Decastro, M.-E., Sueiro, R.-A. and Leiro, J.-M. (2016) Presence of an isoform of H+-pyrophosphatase located in the alveolar sacs of a scuticociliate parasite of turbot: physiological consequences. Parasitology, 143(5), pp. 576-587. (doi: 10.1017/S0031182015001997) (PMID:26932195)

Abstract

H+-pyrophosphatases (H+-PPases) are integral membrane proteins that couple pyrophosphate energy to an electrochemical gradient across biological membranes and promote the acidification of cellular compartments. Eukaryotic organisms, essentially plants and protozoan parasites, contain various types of H+-PPases associated with vacuoles, plasma membrane and acidic Ca+2 storage organelles called acidocalcisomes. We used Lysotracker Red DND-99 staining to identify two acidic cellular compartments in trophozoites of the marine scuticociliate parasite Philasterides dicentrarchi: the phagocytic vacuoles and the alveolar sacs. The membranes of these compartments also contain H+-PPase, which may promote acidification of these cell structures. We also demonstrated for the first time that the P. dicentrarchi H+-PPase has two isoforms: H+-PPase 1 and 2. Isoform 2, which is probably generated by splicing, is located in the membranes of the alveolar sacs and has an amino acid motif recognized by the H+-PPase-specific antibody PABHK. The amino acid sequences of different isolates of this ciliate are highly conserved. Gene and protein expression in this isoform are significantly regulated by variations in salinity, indicating a possible physiological role of this enzyme and the alveolar sacs in osmoregulation and salt tolerance in P. dicentrarchi.

• Item Type: Articles
• Additional Information: This study was financially supported by the Ministerio de Economía y Competitividad (Spain) under grant agreement AGL2014-57125-R, the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 634429 (PARAFISHCONTROL), and by the Xunta de Galicia (Spain) under grant agreement GPC2014/069.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Mallo, Dr Natalia
• Authors: Mallo, N., Lamas, J., Defilipe, A.-P., Decastro, M.-E., Sueiro, R.-A., and Leiro, J.-M.
• College/School: College of Medical Veterinary and Life Sciences > School of Infection & Immunity
• Journal Name: Parasitology
• Publisher: Cambridge University Press
• ISSN: 0031-1820
• ISSN (Online): 1469-8161
• Published Online: 02 March 2016