摘要
Sp7/Osterix as a zinc finger transcription factor is expressed specifically in osteoblasts. Embryonic lethality of Sp7 knockout mice, however, has prevented from examining the functions of Sp7 in osteoblast and bone formation in live animals. Here we used TALEN, a versatile genome-editing tool, to generate one zebrafish sp7 mutant line. Homozygous sp7-/- mutant zebrafish are able to survive to adulthood. Alizarin Red staining and Micro-CT analysis showed that sp7-/- larvae and adult fish fail to develop normal opercula, and display curved tail fins and severe craniofacial malformation, while Alcian Blue staining showed no obvious cartilage defects in sp7-/- fish. Quantitative RT-PCR showed that a number of osteoblast markers including sppl, phex, collala, and collalb are significantly down-regulated in sp7-/- fish. Furthermore, col10a1a, whose ortholog is the cartilage marker in mice, was shown to be a novel downstream gene of Sp7 as an osteoblast marker in zebrafish. Together, these results suggest that Sp7 is required for zebrafish bone development and zebrafish sp7 mutants provide animal models for investigating novel aspects of bone development.
Sp7/Osterix as a zinc finger transcription factor is expressed specifically in osteoblasts.Embryonic lethality of Sp7 knockout mice,however,has prevented from examining the functions of Sp7 in osteoblast and bone formation in live animals.Here we used TALEN,a versatile genome-editing tool,to generate one zebrafish sp7 mutant line.Homozygous sp7-/- mutant zebrafish are able to survive to adulthood.Alizarin Red staining and Micro-CT analysis showed that sp7-/- larvae and adult fish fail to develop normal opercula,and display curved tail fins and severe craniofacial malformation,while Alcian Blue staining showed no obvious cartilage defects in sp7-/- fish.Quantitative RT-PCR showed that a number of osteoblast markers including spp1,phex,col1 ala,and col1a1 b are significantly down-regulated in sp7-/- fish.Furthermore,col10a1 a,whose ortholog is the cartilage marker in mice,was shown to be a novel downstream gene of Sp7 as an osteoblast marker in zebrafish.Together,these results suggest that Sp7 is required for zebrafish bone development and zebrafish sp7 mutants provide animal models for investigating novel aspects of bone development.
基金
supported by the grants from National High Technology Research and Development Program of China (2011AA100402-2)
the National Natural Science Foundation of China (NSFC) (31271356, 31030062, 81070455)
National Basic Research Program of China (2012CB947600)
the Jiangsu Distinguished Professorship Program (SR13400111)
the Natural Science Foundation of Jiangsu Province (BK2012052)
the Priority Academic Program Development (PAPD) of Jiangsu Higher Education Institutions (YX13400214)
the High-Level Innovative Team of Jiangsu Province
the ‘‘333” project of Jiangsu Province (BRA2015328)
