Journal Article
Maternal control of visceral asymmetry evolution in Astyanax cavefish
Ma, L., Ng, M., Shi, J., Gore, A.V., Castranova, D., Weinstein, B.M. and Jeffery, W.R.
Record Number:
5344
Year:
2021
Journal:
Scientific Reports
Pages:
1-14
Volume:
11:10312
Notes:
Supplementary Information The online version contains supplementary material available at https:// doi. org/10.1038/ s41598- 021- 89702-6.
Open Access This article is licensed under a Creative Commons Attribution 4.0 International
License
Abstract:
The direction of visceral organ asymmetry is highly conserved during vertebrate evolution with heart
development biased to the left and pancreas and liver development restricted to opposing sides
of the midline. Here we show that reversals in visceral organ asymmetry have evolved in Astyanax
mexicanus, a teleost species with interfertile surface-dwelling (surface fish) and cave-dwelling
(cavefish) forms. Visceral organ asymmetry is conventional in surface fish but some cavefish have
evolved reversals in heart, liver, and pancreas development. Corresponding changes in the normally
left-sided expression of the Nodal-Pitx2/Lefty signaling system are also present in the cavefish lateral
plate mesoderm (LPM). The Nodal antagonists lefty1 (lft1) and lefty2 (lft2), which confine Nodal
signaling to the left LPM, are expressed in most surface fish, however, lft2, but not lft1, expression
is absent during somitogenesis of most cavefish. Despite this difference, multiple lines of evidence
suggested that evolutionary changes in L-R patterning are controlled upstream of Nodal-Pitx2/Lefty
signaling. Accordingly, reciprocal hybridization of cavefish and surface fish showed that modifications
of heart asymmetry are present in hybrids derived from cavefish mothers but not from surface fish
mothers. The results indicate that changes in visceral asymmetry during cavefish evolution are
influenced by maternal genetic effects.
Times Cited:
1
Relevent Species: