Evolutionary transition to freshwater by ancestral marine palaemonids: evidence from osmoregulation in a tide pool shrimp


Autoria(s): Augusto, Alessandra da Silva; Pinheiro, Adriana Silva; Greene, Lewis Joel; Laure, Helen Julie; McNamara, John Campbell
Contribuinte(s)

Universidade Estadual Paulista (UNESP)

Data(s)

20/05/2014

20/05/2014

01/01/2009

Resumo

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Processo FAPESP: 96/01842-8

Processo FAPESP: 01/00576-2

Processo FAPESP: 01/01763-5

The transition from marine/brackish waters to freshwater habitats constitutes a severe osmotic and ionic challenge, and successful invasion has demanded the selection of morphological, physiological, biochemical and behavioral adaptations. We evaluated short-term (1 to 12 h exposure) and long-term (5 d acclimation), anisosmotic extracellular (osmolality, [Na(+), Cl(-)]) and long-term isosmotic intracellular osmoregulatory capability in Palaemon northropi, a neotropical intertidal shrimp. F northropi survives well and osmo- and ionoregulates strongly during short- and long-term exposure to 5-45 parts per thousand salinity, consistent with its rocky tide pool habitat subject to cyclic salinity fluctuations, Muscle total free amino acid (FAA) concentrations decreased by 63% in shrimp acclimated to 5%. salinity, revealing a role in hypoosmotic cell volume regulation; this decrease is mainly a consequence of diminished glycine, arginine and proline. Total FAA contributed 31% to muscle intracellular osmolality at 20 parts per thousand, an isosmotic salinity, and decreased to 13% after acclimation to 5 parts per thousand. Gill and nerve tissue FAA concentrations remained unaltered. These tissue-specific responses reflect efficient anisosmotic and anisoionic extracellular regulatory mechanisms, and reveal the dependence of muscle tissue on intracellular osmotic effectors. FAA concentration is higher in P. northropi than in diadromous and hololimnetic palaemonids, confirming muscle FAA concentration as a good parameter to evaluate the degree of adaptation to dilute media. The osmoregulatory capability of P. northropi may reflect the potential physiological capacity of ancestral marine palaemonids to penetrate into dilute media, and reveals the importance of evaluating osmoregulatory processes in endeavors to comprehend the invasion of dilute media by ancestral marine crustaceans.

Formato

113-122

Identificador

http://dx.doi.org/10.3354/ab00183

Aquatic Biology. Oldendorf Luhe: Inter-research, v. 7, n. 1-2, p. 113-122, 2009.

1864-7790

http://hdl.handle.net/11449/536

10.3354/ab00183

WOS:000272490500010

Idioma(s)

eng

Publicador

Inter-research

Relação

Aquatic Biology

Direitos

openAccess

Palavras-Chave #Freshwater invasion #Marine-freshwater transition #Physiological adaptation #Osmotic and ionic regulation #Free amino acids #Palaemonid shrimp #Palaemon northropi
Tipo

info:eu-repo/semantics/conferenceObject