Transcriptomes reveal the genetic mechanisms underlying ionic regulatory adaptations to salt in the crab-eating frog.

Seleccionado por: Ruth 

Abstract

The crab-eating frog, Fejervarya cancrivora, is the only frog that lives near seas. It tolerates increasedenvironmental concentrations of sodium, chloride and potassium partly by raising ion and urea levels in its blood plasma. The molecular mechanism of the adaptation remains rarely documented. Herein, we analyze transcriptomes of the crab-eating frog and its closely related saline-intolerant species, F. limnocharis, to explore the molecular basis of adaptations to such extreme environmental conditions. Analyses reveal the potential genetic mechanism underlying the adaptation to salinity for the crabeating frog. Genes in categories associated with ion transport appear to have evolved rapidly in F. cancrivora. Both positively selected and differentially expressed genes exhibit enrichment in the GO category regulation of renal sodium excretion. In this category, the positively selected sites of ANPEP and AVPR2 encode CD13 and V2 receptors, respectively; they fall precisely on conserved domains. More differentially expressed rapidly evolved genes occur in the kidney of F. cancrivora than in F. limnocharis. Four genes involved in the regulation of body fluid levels show signs of positive selection and increased expression. Significant up-regulation occurs in several genes of F. cancrivora associated with renin-angiotensin system and aldosterone-regulated sodium reabsorption pathways, which relate to osmotic regulation.


En el  artículo se trata de explicar las adaptaciones genéticas de una ranita a ambientes salobres, mediante la identificación de perfiles de expresión para genes candidatos implicados en la adaptación a estos ambientes. Este artículo es de mi interés dada la naturaleza de mi trabajo, donde planteo estudiar salamandras que aparentemente se han adaptado a ambientes más secos comparadas con sus especies hermanas que habitan en ambientes húmedos y utilizando ahora estas herramientas (transcriptoma) es posible identificar genes candidatos a selección.