INTEGRATION AND GERM-LINE TRANSMISSION OF A PSEUDOTYPED RETROVIRAL VECTOR IN ZEBRAFISH

The zebrafish is rapidly becoming a popular model system for the study of vertebrate development because it is ideal for both embryological studies and genetic analysis. To determine if a retroviral vector pseu dotyped with the envelope glycoprotein of the vesicular stomatitis vir us could infect zebrafish embryos, and in particular, the cells destin ed to become the germ line, a pseudotyped virus was injected into blas tula-stage zebrafish embryos. Fifty-one embryos were allowed to develo p and eight transmitted proviral DNA to their progeny. Founders were m osaic, but as expected, transgenic F-1's transmitted proviral DNA in a Mendelian fashion to the F-2 progeny. Transgenic F-1 fish inherited a single integrated provirus, and a single founder could transmit more than one viral integration to its progeny. These results demonstrate t hat this pantropic pseudotyped vector, originally developed for human gene therapy, will make the use of retroviral vectors in zebrafish pos sible.