Comparison of Myosepta Development and Transcriptome Profiling between Blunt Snout Bream with and Tilapia without Intermuscular Bones
Jia-Jia Zhou,
Yong-Jie Chang,
Yu-Long Chen,
Xu-Dong Wang,
Qing Liao,
Rui-Hui Shi,
Ze-Xia Gao
Affiliations
Jia-Jia Zhou
College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, No. 1 Shizishan Street, Hongshan District, Wuhan 430070, China
Yong-Jie Chang
College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, No. 1 Shizishan Street, Hongshan District, Wuhan 430070, China
Yu-Long Chen
College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, No. 1 Shizishan Street, Hongshan District, Wuhan 430070, China
Xu-Dong Wang
College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, No. 1 Shizishan Street, Hongshan District, Wuhan 430070, China
Qing Liao
College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, No. 1 Shizishan Street, Hongshan District, Wuhan 430070, China
Rui-Hui Shi
College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, No. 1 Shizishan Street, Hongshan District, Wuhan 430070, China
Ze-Xia Gao
College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, No. 1 Shizishan Street, Hongshan District, Wuhan 430070, China
Intermuscular bones (IBs) are small spicule-like bones located in the myosepta of basal teleosts, which negatively affect the edibleness and economic value of fish. Blunt snout bream (Megalobrama amblycephala, with epineural and epipleural IBs) and tilapia (Oreochromis niloticus, without epineural and epipleural IBs) are two major aquaculture species and ideal models for studying the formation mechanisms of fish IBs. Here, we compared myosepta development between M. amblycephala and O. niloticus, based on histological analysis, transcriptome profiling, and expression analysis of bone-related genes. The histological results showed that dye condensation began to appear in the myosepta 20 days post hatching (dph) in M. amblycephala, and IBs could be clearly observed 50 dph in the myosepta, based on different staining methods. However, in O. niloticus, dye condensation was not observed in the myosepta from 10 to 60 dph. Differentially expressed genes (DEGs) at different developmental stages were screened by comparing the transcriptomes of M. amblycephala and O. niloticus, and KEGG analysis demonstrated that these DEGs were enriched in many bone-related pathways, such as focal adhesion, calcium, and Wnt signaling pathways. Quantitative PCR was performed to further compare the expression levels of some bone-related genes (scxa, scxb, runx2a, runx2b, bgp, sp7, col1a2, entpd5a, entpd5b, phex, alpl, and fgf23). All the tested genes (except for alpl) exhibited higher expression levels in M. amblycephala than in O. niloticus. A comparison of the dorsal and abdominal muscle tissues between the two species also revealed significant expression differences for most of the tested genes. The results suggest that scxa, scxb, runx2a, runx2b, entpd5a, col1a2, and bgp may play important roles in IB development. Our findings provide some insights into the molecular mechanisms of IB formation, as well as clues for further functional analysis of the identified genes to better understand the development of IBs.
