Genome wide transcriptional changes underlie gradual and recurrent adaptation to protein malnutrition in zebrafish

The useful part

Raising pllp homozygous mutants surviving to adulthood and in-crossing them for multiple generations resulted in a recovery of survival and growth, even when fed a low protein diet. To uncover mechanisms underlying this phenomenon, we compared the older adapted pllp allele with genetically related wild type (WT) fish and a newly generated pllp mutant allele. Genetic analyses indicate that these divergent phenotypes emerge gradually over generations and can recur in an independently generated pllp allele upon inbreeding and natural selection.

Details worth keeping

by Siyao Wang, Laura Childers, Fernando Martinez III, Michel Bagnat, Jieun Park Lysosome-rich enterocytes (LREs) are a specialized population of intestinal cells that mediate the uptake and absorption of dietary proteins in fish and neonatal mammals. Previously, we reported that in zebrafish loss of Plasmolipin (pllp), an endosomal membrane protein highly expressed in LREs, impairs LRE differentiation and dietary protein absorption, resulting in marked reduction in survival rates. Using transcriptome profiling and quantitative protein absorption assays, we found that the adapted pllp mutants exhibit upregulation of LRE endocytic components associated with a capacity for protein absorption that exceeds that of WT.