ANALYSIS OF OSTEOPOROSIS-LIKE PHENOTYPE OF THE RANKL: HSE:CFP HOMOZYGOUS TRANSGENIC MEDAKA FISH LINE C1C6 MODEL FOR OSTEOPOROSIS

DOI: 10.18173/2354-1059.2020-0060

Tóm tắt

The transgenic medaka rankl: HSE:CFP was generated to model human osteoporosis, a bone disease characterized by reduced bone mass, deteriorated bone structure, and high risk of bone fragility. The fish expresses the transgene rankl encoding for the osteoclast-stimulating factor Rankl under the control of a heat-inducible promotor so it could exhibit damaged mineralized bone structures or an osteoporosis-like phenotype upon a heatshock. In the previous study, the original transgenic fish carrying multiple insertions of the transgene were segregated into genetically homogeneous lines, each had one insertion of the transgene, including the line named c1c6 that was heterozygous for the transgene. However, for the studies to screen for substances of anti-osteoporosis potential, homozygous fish is very important to provide large numbers of heterozygous embryos. In this study, we testcrossed 12 fish of the F5 generation, which were offspring obtained from inbreeding of heterozygous F4 siblings, with wild type fish and found 3 female and 3 male F5 fish homozygous for the transgene. These F5 individuals were inbred to generate homozygous fish of F6 and F7 generations. Osteoporosis-like phenotype and levels of bone damage of these homozygous fish larvae were analyzed and compared with those of heterozygous larvae. Results showed that homozygous c1c6 Rankl fish had stable osteoporosis-like phenotype but a lower level of bone mineralized damage (70,6% for F6 and 65,8% for F7) than heterozygous fish (88,4% for F6 and 81,1% for F7). These homozygous fish are essential for further studies to screen for anti-osteoporosis substances.