Nie Chun-Hong, Wan Shi-Ming, Tomljanovic Tea, Treer Tomislav, Hsiao Chung-Der, Wang Wei-Min, Gao Ze-Xia
College of Fisheries, Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education/Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Huazhong Agricultural University, Wuhan, Hubei, 430070, China.
Collaborative Innovation Center for Healthy Freshwater Aquaculture of Hubei Province, Wuhan, 430070, China.
BMC Genomics. 2017 Feb 10;18(1):147. doi: 10.1186/s12864-017-3530-z.
Intermuscular bones (IBs) and ribs both are a part of skeletal system in teleosts, but with different developing process. The chemical composition of fish IBs and ribs as well as the underlying mechanism about their development have not been investigated. In the present study, histological structures showed that one bone cavity containing osteoclasts were existed in ribs, but not in IBs of Megalobrama amblycephala. We constructed the first proteomics map for fish bones including IBs and ribs, and identified the differentially expressed proteins between IBs and ribs through iTRAQ LC-MS/MS proteomic analysis.
The proteins extracted from IBs and ribs at 1- to 2-year old M. amblycephala were quantified 2,342 proteins, with 1,451 proteins annotated with GO annotation in biological processes, molecular function and cellular component. A number of bone related proteins as well as pathways were identified in the study. A total of 93 and 154 differently expressed proteins were identified in comparison groups of 1-IB-vs-1-Rib and 2-IB-vs-2-Rib, which indicated the obvious differences of chemical composition between these two bone tissues. The two proteins (vitronectin b precursor and matrix metalloproteinase-2) related to osteoclasts differentiation were significantly up-regulated in ribs compared with IBs (P < 0.05), which was in accordance with the results from histological structures. In comparison groups of 1-IB-vs-2-IB and 1-Rib-vs-2-Rib, 33 and 51 differently expressed proteins were identified and the function annotation results showed that these proteins were involved in regulating bone development and differentiation. Subsequently, 11 and 13 candidate proteins in comparison group of 1-IB-vs-1-Rib and 1-IB-vs-2-IB related to bone development were validated by MRM assays.
Our present study suggested the different key proteins involved in the composition of fish ribs and IBs as well as their growth development. These findings could provide important clues towards further understanding of fish skeletal system and the roles of proteins playing in regulating diverse biological processes in fish.
肌间骨（IBs）和肋骨都是硬骨鱼类骨骼系统的一部分，但发育过程不同。鱼类肌间骨和肋骨的化学成分及其发育的潜在机制尚未得到研究。在本研究中，组织学结构显示，在鳙鱼的肋骨中存在一个含有破骨细胞的骨腔，但在肌间骨中不存在。我们构建了首个包括肌间骨和肋骨的鱼骨蛋白质组图谱，并通过iTRAQ LC-MS/MS蛋白质组分析鉴定了肌间骨和肋骨之间差异表达的蛋白质。
对1至2龄鳙鱼的肌间骨和肋骨中提取的蛋白质进行定量分析，共鉴定出2342种蛋白质，其中1451种蛋白质在生物过程、分子功能和细胞成分方面有GO注释。本研究鉴定出了许多与骨相关的蛋白质以及通路。在1-IB-vs-1-Rib和2-IB-vs-2-Rib比较组中分别鉴定出93种和154种差异表达蛋白质，这表明这两种骨组织在化学成分上存在明显差异。与肌间骨相比，与破骨细胞分化相关的两种蛋白质（玻连蛋白b前体和基质金属蛋白酶-2）在肋骨中显著上调（P < 0.05），这与组织学结构结果一致。在1-IB-vs-2-IB和1-Rib-vs-2-Rib比较组中，分别鉴定出33种和51种差异表达蛋白质，功能注释结果表明这些蛋白质参与调节骨发育和分化。随后，通过MRM分析验证了1-IB-vs-1-Rib和1-IB-vs-2-IB比较组中11种和13种与骨发育相关的候选蛋白质。
我们目前的研究表明，参与鱼类肋骨和肌间骨组成及其生长发育的关键蛋白质不同。这些发现可为进一步了解鱼类骨骼系统以及蛋白质在调节鱼类多种生物学过程中所起的作用提供重要线索。
