Acidocalcisomes as calcium- and polyphosphate-storage compartments during embryogenesis of the insect rhodnius prolixus stahl

Autor: Ramos, Isabela Barbosa, Gomes, Fabio Mendonça, Koeller, Carolina Macedo, Saito, Katsuharu, Heise, Norton, Masuda, Hatisaburo, Docampo, Roberto, Souza, Wanderley de, Machado, Ednildo de Alcântara, Miranda, Kildare Rocha de
Jazyk: angličtina
Rok vydání: 2011
Zdroj: Repositório Institucional do INMETRO
Instituto Nacional de Metrologia, Qualidade e Tecnologia (INMETRO)
instacron:INMETRO
Popis: Submitted by Lívia Oliveira (livia.oliveira2@hotmail.com) on 2012-06-22T13:18:03Z No. of bitstreams: 1 Plos One,v.6,n11, e27276, 2011.pdf: 1347454 bytes, checksum: b0ee3f52902baf6ce0e14aa8450c325d (MD5) Approved for entry into archive by Regina Mello(mrmello@inmetro.gov.br) on 2012-06-25T16:18:11Z (GMT) No. of bitstreams: 1 Plos One,v.6,n11, e27276, 2011.pdf: 1347454 bytes, checksum: b0ee3f52902baf6ce0e14aa8450c325d (MD5) Made available in DSpace on 2012-06-27T18:32:38Z (GMT). No. of bitstreams: 1 Plos One,v.6,n11, e27276, 2011.pdf: 1347454 bytes, checksum: b0ee3f52902baf6ce0e14aa8450c325d (MD5) Previous issue date: 2011 Background: The yolk of insect eggs is a cellular domain specialized in the storage of reserve components for embryo development. The reserve macromolecules are stored in different organelles and their interactions with the embryo cells are mostly unknown. Acidocalcisomes are lysosome-related organelles characterized by their acidic nature, high electron density and large content of polyphosphate bound to several cations. In this work, we report the presence of acidocalcisome-like organelles in eggs of the insect vector Rhodnius prolixus. Methodology/Principal findings: Characterization of the elemental composition of electron-dense vesicles by electron probe X-ray microanalysis revealed a composition similar to that previously described for acidocalcisomes. Following subcellular fractionation experiments, fractions enriched in acidocalcisomes were obtained and characterized. Immunofluorescence showed that polyphosphate polymers and the vacuolar proton translocating pyrophosphatase (V-H+-PPase, considered as a marker for acidocalcisomes) are found in the same vesicles and that these organelles are mainly localized in the egg cortex. Polyphosphate quantification showed that acidocalcisomes contain a significant amount of polyphosphate detected at day-0 eggs. Elemental analyses of the egg fractions showed that 24.560.65% of the egg calcium are also stored in such organelles. During embryogenesis, incubation of acidocalcisomes with acridine orange showed that these organelles are acidified at day-3 (coinciding with the period of yolk mobilization) and polyphosphate quantification showed that the levels of polyphosphate tend to decrease during early embryogenesis, being approximately 30% lower at day-3 compared to day-0 eggs. Conclusions: We found that acidocalcisomes are present in the eggs and are the main storage compartments of polyphosphate and calcium in the egg yolk. As such components have been shown to be involved in a series of dynamic events that may control embryo growth, results reveal the potential involvement of a novel organelle in the storage and mobilization of inorganic elements to the embryo cells. 11 p. : il.
Databáze: OpenAIRE