Int. J. Dev. Biol. In Press
doi: 10.1387/ijdb.210066rs
© UPV/EHU Press

Expression of two uncharacterized protein coding genes in zebrafish lateral line system

Sana Fatma1,2, Ravindra Kumar1, Anshuman Dixit1 and Rajeeb K. Swain*,1

1Institute of Life Sciences, Nalco Square, Chandrasekharpur, Bhubaneswar, and 2Manipal Academy of Higher Education, Manipal, Karnataka, India

ABSTRACT The lateral line system is a mechanosensory organ of fish and amphibians that detects changes in water flow and is formed by the coordinated action of many signalling pathways. These signalling pathways can easily be targeted in zebrafish using pharmacological inhibitors to decipher their role in lateral line system development at cellular and molecular level. We have identified two uncharacterized proteins, whose mRNA are expressed in the lateral line system of zebrafish. One of these proteins, uncharacterized protein LOC564095 precursor is conserved across vertebrates and its mRNA is expressed in posterior lateral line primordium (pLLP). The other uncharacterized protein LOC100536887 is present only in the teleost fishes and its mRNA is expressed in neuromasts. We show that inhibition of retinoic acid (RA) signalling reduces the expression of both of these uncharacterized genes. It is reported that inhibition of RA signalling during gastrulation starting at 7 hours post fertilization (hpf) abrogates pLLP formation and inhibition of RA signalling at 10 hpf delays the initiation of pLLP migration. Here, we show that inhibition of RA signalling before and during segmentation (9-16 hpf) results in delayed initiation and reduced speed of pLLP migration as well as inhibition of posterior neuromasts formation.

Keywords:

Lateral line system, posterior lateral line primordium, neuromasts, uncharacterized proteins

*Corresponding author e-mail: rkswain@ils.res.in