Functional analysis of hmx-1 gene in the developing embryo

点击翻译按钮获取中文摘要

The three genes of the murine Hmx family, designated Hmx1, Hmx2, and Hmx3, are expressed in the sensory nerve and uterus that suggest a functional role in development of those organs and/or pregnancy. The Hmx3 knockout mice, as suspected by the expressed region, show abnormal structure of inner ear and implantation defect in homozygote mice. To analyze the function of Hmx1 gene in the organ development and pregnancy, we adopted the homologous recombination technique. Homozygous targeted disruption of Hmx1 gene result in lethality at embryonic day 6-7 in intercross of F1 (129/Sv : C57BL/6) heterozygote. But this lethality is rescued in F2 or F3 intercross. This phenomenon suggest that rescue gene may exist in C57BL/6 mice genome. In the present state, however, it is unclear whether the genotype of mother or embryo could rescue the lethal phenotye. Once homozygote mice develop beyond the E5-E7 critical date, they are completely normal even in the tissues in which Hmx1 is expressed.