Comparative Transcriptomic Analysis of Regenerated Skins Provides Insights into Cutaneous Air-Breathing Formation in Fish.

Songqian Huang,Xiaojuan Cao,Bing Sun,Jinli Zhu,Chuanshu Liu,Lijuan Yang,Longfei Huang,Jian Gao

doi:10.3390/biology10121294

Songqian Huang, Xiaojuan Cao + Show 6 more

Open Access

https://doi.org/10.3390/biology10121294

Copy DOI

Abstract

Simple SummaryCutaneous air-breathing is one of the air-breathing patterns in bimodal respiration fishes, while little is known about its underlying formation mechanisms. The skin regeneration of loach (Misgurnus anguillicaudatus, a cutaneous air-breathing fish) and yellow catfish (Pelteobagrus fulvidraco, a water-breathing fish) were first investigated through morphological and histological observations. Then, the original skins (OS: MOS, POS) and regenerated skins (RS: MRS, PRS) when their capillaries were the most abundant during healing, of the two fish species were collected for high-throughput RNA-seq. A total of 56,054 unigenes and 53,731 unigenes were assembled in loach and yellow catfish, respectively. A total of 640 (460 up- and 180 down-regulated) and 4446 (2340 up- and 2106 down-regulated) differentially expressed genes (DEGs) were respectively observed in RS/OS of loach and yellow catfish. Subsequently, the two DEG datasets were clustered in GO, KOG, and KEGG databases, and further analyzed by comparison and screening. Consequently, tens of genes and thirteen key pathways were targeted, indicating that these genes and pathways had strong ties to cutaneous skin air-breathing in loach. This study provides new insights into the formation mechanism of cutaneous air-breathing and also offers a substantial contribution to the gene expression profiles of skin regeneration in fish.Cutaneous air-breathing is one of the air-breathing patterns in bimodal respiration fishes, while little is known about its underlying formation mechanisms. Here, we first investigated the skin regeneration of loach (Misgurnus anguillicaudatus, a cutaneous air-breathing fish) and yellow catfish (Pelteobagrus fulvidraco, a water-breathing fish) through morphological and histological observations. Then, the original skins (OS: MOS, POS) and regenerated skins (RS: MRS, PRS) when their capillaries were the most abundant (the structural foundation of air-breathing in fish) during healing, of the two fish species were collected for high-throughput RNA-seq. A total of 56,054 unigenes and 53,731 unigenes were assembled in loach and yellow catfish, respectively. A total of 640 (460 up- and 180 down-regulated) and 4446 (2340 up- and 2106 down-regulated) differentially expressed genes (DEGs) were respectively observed in RS/OS of loach and yellow catfish. Subsequently, the two DEG datasets were clustered in GO, KOG and KEGG databases, and further analyzed by comparison and screening. Consequently, tens of genes and thirteen key pathways were targeted, indicating that these genes and pathways had strong ties to cutaneous skin air-breathing in loach. This study provides new insights into the formation mechanism of cutaneous air-breathing and also offers a substantial contribution to the gene expression profiles of skin regeneration in fish.

Highlights

It is well acknowledged that gill respiration is not the only way for fish to obtain oxygen
15 key pathways and 25 key genes were identified by a developmental transcriptome analysis, presenting relationship to the formation of intestinal air-breathing in loach (Misgurnus anguillicaudatus) in our previous research [10]
We examined the skin regeneration of a cutaneous air-breathing loach M. anguillicaudatus and a water-breathing yellow catfish P. fulvidraco with respect to the morphological and histological observations and gene expression profiles

Summary

Introduction

It is well acknowledged that gill respiration is not the only way for fish to obtain oxygen. A transcriptome analysis of Channa argus involved gill and the suprabranchial chamber (an ABO) was performed, and screened out a batch of genes probably related to the formation of air-breathing, such as vascular endothelial growth factor (vegf ) and fibroblast growth factor receptor (fgfr) [7]. 15 key pathways and 25 key genes were identified by a developmental transcriptome analysis, presenting relationship to the formation of intestinal air-breathing in loach (Misgurnus anguillicaudatus) in our previous research [10]. Large number of genes and pathways have been proven involved in gas exchange process and vascularization in vertebrate [13,14,15], but it is rarely reported to attach these genes and pathways to fish air-breathing formation

Methods

Results

Discussion

Conclusion