alt transport by the gill Na+-K+-2Cl(-) symporter in palaemonid shrimps: exploring physiological, molecular and evolutionary landscape

Autor(es)

Maraschi, Anieli Cristina ^[1] ; Faria, Samuel Coelho ^[2] ; McNamara, John Campbell ^{[1, 2]}

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Fac Filosofia Ciencias & Letras Ribeirao Preto, Dept Biol, BR-14040901 Ribeirao Preto, SP - Brazil

^[2] Univ Sao Paulo, Ctr Biol Marinha, BR-11600000 Sao Sebastiao, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY A-MOLECULAR & INTEGRATIVE PHYSIOLOGY; v. 257, JUL 2021.
• Citações Web of Science: 1

Resumo

Palaemonid shrimps inhabit osmotic niches from marine to continental waters. They hyper-regulate hemolymph osmolality and ionic concentrations in dilute media, hypo-regulating in concentrated media. Their gill epithelia express ion transporters like the Na+-K+-2Cl(-) symporter (NKCC) thought to play a role in salt secretion. To examine Cl- hypo-regulatory capability and phylogenetic correlations between gill NKCC mRNA levels and protein expression, we used palaemonids ranging from marine tide pools through estuaries (Palaemon) to coastal and continental fresh waters (Macrobrachium). We established the species' upper critical salinity limits (UL50) and short- (24 h) and long-term (120h) hypo-regulatory abilities at salinities of 80% of their UL50's (80%UL50). The Palaemon species exhibited the highest UL50's and greatest hypo-regulatory capabilities; among the Macrobrachium species, UL50's were higher in the diadromous than in the hololimnetic species. While basal transcript levels of gill NKCC mRNA were highest in P. pandaliformis, levels were unaffected by salinity or exposure time in all species. However, gill NKCC protein abundance increased after 120-h exposure at the 80%UL50 in all Macrobrachium species, except M. potiuna. Unexpectedly, hemolymph hyper-osmoregulatory capability in acclimatization media correlated with gill NKCC protein synthesis, while gill NKCC mRNA expression correlated with hemolymph hyper-Cl- regulation in Macrobrachium. These findings, together with the evolutionary history of osmoregulation in this shrimp clade, suggest a role for the gill NKCC symporter in both salt uptake and secretion. The evolution of NKCC protein expression responsiveness, unlike hemolymph hypo-regulation and NKCC mRNA expression, may have been driven by environmental salinity during niche radiation. Summary statement: While mRNA expression of the gill Na+-K+-2Cl(-) symporter is unchanged during acclimation of palaemonid shrimps to saline media, protein expression is up regulated, revealing a role in chloride secretion. (AU)

• Processo FAPESP: 15/00131-3 - A secreção de cloreto pelo epitélio branquial em camarões e caranguejos de diferentes nichos osmóticos: uma investigação fisiológica e molecular do simportador Na+-K+-2Cl-
• Beneficiário: John Campbell McNamara
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 13/23906-5 - O cotransportador Na+, K+, 2Cl- e a secreção de cloreto branquial em camarões Palaemonidae (Decapoda, Crustacea): padrões moleculares, fisiológicos e evolutivos
• Beneficiário: Anieli Cristina Maraschi
• Modalidade de apoio: Bolsas no Brasil - Doutorado