1. Department of Medical Oncology, Hubei Cancer Hospital, Wuhan, Hubei 430079, China.
2. Department of Histology and Embryology, School of Basic Medical Science, Wuhan University, Wuhan, Hubei 430071, China.
3. Department of Anatomy, Hubei University of Medicine, Shiyan, Hubei442000, China.
4. Department of Hematology, Wuhan integrated TCM & Western Medicine hospital, Wuhan, Hubei 430030, China.
5. Department of Ophthalmology, Zhongnan Hospital of Wuhan University, Wuhan, Hubei 430030, China.
6. Department of Hematology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China.
Zebrafish (Danio rerio) are an attractive vertebrate model for the molecular dissection of disease mechanisms. Janus kinase (JAK)/signal transducer and activator of transcription (stat) has been defined through studies of cytokine signaling pathways in mammals. Here, we examined the expression level of Jak2a, which is a homolog of mammalian jak2 in zebrafish, by quantitative reverse transcriptase (RT)-PCR, and the peak of mRNA expression occurred at 3.75 hours post fertilization (hpf). The overexpression of Jak2a was proven by real-time Q-PCR and Western blot in 1-4-cell stage embryos injected with 400 ng/µl full-length jak2a mRNA as well as gfi1.1, gata1, mpo and β-embryonic hemoglobin as detected by real-time Q-PCR. Moreover, jak2a mRNA significantly increased the GFP+ population in the transgenic zebrafish lines Tg (gata1: gfp) (uninjected embryos: 17.22±1.70%; embryos injected with jak2a mRNA: 21.31±2.11%, p<0.01) and Tg (mpo: gfp) (uninjected embryos: 3.86±1.94; embryos injected with jak2a mRNA: 6.64±1.30%, p<0.01) compared with the control group. Thus, our data indicate that Jak2a plays an important role in erythropoiesis and myeloid hematopoiesis.
Keywords: zebrafish, Jak2a, mRNA, overexpression, hematopoiesis