The CYP19A1 gene encodes an aromatase that is a member of the cytochrome P450 superfamily, also known as estrogen synthase, an enzyme responsible for a key step in estrogen biosynthesis. Cytochrome P450 proteins are monooxygenases that catalyze many reactions involved in drug metabolism and the synthesis of cholesterol, steroids, and other lipids. This protein is located in the endoplasmic reticulum and catalyzes the final step in estrogen biosynthesis. The CYP19A1 aromatase is responsible for aromatizing androgens into estrogens and can be found in many tissues, including the gonads (granulosa cells), brain, adipose tissue, placenta, blood vessels, skin, and bone, as well as tissues from endometriosis, uterine fibroids, breast cancer, and endometrial carcinoma. It is an important factor in sexual development ^[1-2]. The Cyp19a1-IRES-Cre mice were constructed using gene editing technology to insert an IRES-Cre element downstream of the stop codon of the endogenous Cyp19a1 gene in mice. The expression pattern of Cre recombinase is similar to that of the endogenous gene. When this strain is crossed with mice containing loxP sites, sequence recombination between loxP sites mediated by Cre recombinase can occur in the granulosa cells of the ovaries of offspring mice.

2300009A05Rik is located on chromosome 9 of mice. Nuclease Technology will be used to design sgRNA; 2300009A05Rik knockout mice will be obtained by applying high-throughput electroporation of fertilized eggs. After sexual maturity, sperm were collected for cryopreservation.

Polr2e is located on chromosome 10 of mice. SgRNA and ssDNA will be designed using Nuclease Technology; Polr2e conditional knockout mice will be obtained by high-throughput electroporation of fertilized eggs. After sexual maturity, sperm will be collected for cryopreservation.

Cyp19a1 is located on chromosome 9 of mice. Nuclease Technology was used to design sgRNA; Cyp19a1 knockout mice were obtained by applying high-throughput electroporation of fertilized eggs. After sexual maturity, sperm were collected for cryopreservation.

Cyp19a1 is located on chromosome 9 of mice. SgRNA and ssDNA were designed using Nuclease Technology; Cyp19a1 conditional knockout mice were obtained by high-throughput electroporation of fertilized eggs. After sexual maturity, sperm were collected for cryopreservation.