Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8318816 | Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology | 2018 | 7 Pages |
Abstract
Midkine (Mdk) is a heparin-binding growth factor that is involved in regulating cell growth, differentiation and migration. Here, we report the isolation and characterization of duplicated mdk genes in blunt snout bream (Megalobrama amblycephala). The mdka and -b genes encode 146 aa and 147 aa peptides, respectively, sharing a sequence identity of 64%. During embryogenesis, mdka mRNA is detectable after 12â¯h post-fertilization (hpf) and mdkb mRNA can be detected after 8â¯hpf, about 4â¯h prior to mdka mRNA. Whole-mount in situ hybridization demonstrated that two paralogs of mdk mRNA were detected in the brain and dorsal neural tube at 16â¯hpf. At 22â¯hpf, mdka mRNA was abundant in the brain and dorsal neural tube, whereas mdkb mRNA were transcribed in the brain and tailbud. Later, at 55â¯hpf, both paralogs were mainly expressed in the brain. Furthermore, both the mdk genes were highly expressed in multiple adult tissues except in the skin and a low expression of mdka in the muscle. In addition, they were differentially inhibited in the liver and intestine with exogenous recombinant human growth hormone, while their mRNA levels were up-regulated in the brain. During starvation, both the mdk genes were significantly up-regulated in the intestine, brain and liver and returned to the control levels following 6â¯days of refeeding. Our results suggest that duplicated mdk genes may play conserved and divergent roles in embryonic development and tissue growth regulation in blunt snout bream.
Related Topics
Life Sciences
Biochemistry, Genetics and Molecular Biology
Biochemistry
Authors
Dan-Dan Guo, Guo-Dong Zheng, Shang-Ke Du, Bo Qin, Xia-Yun Jiang, Shu-Ming Zou,