Int. J. Dev. Biol. 65: 563 - 570 (2021)

https://doi.org/10.1387/ijdb.210066rs

Vol 65, Issue 10-11-12

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

Open Access | Developmental Expression Pattern | Published: 15 November 2021

Sana Fatma^1,2 Ravindra Kumar³, Anshuman Dixit¹ and Rajeeb k. Swain*^,1

¹Institute of Life Sciences, Nalco Square, Chandrasekharpur, Bhubaneswar, ²Manipal Academy of Higher Education, Manipal, Karnataka and ³School of Biotechnology, National Institute of Technology Calicut, Kerala, 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