Background:

• Fibronectin 1 (FN1) is an extracellular matrix protein that plays a crucial role in the occurrence, progression, and metastasis of various tumors. In recent years, FN1 has garnered significant attention as a potential diagnostic biomarker and therapeutic target in multiple cancer studies.

Targeting strategy:

• The exons 1~46 of mouse Fn1 gene that encodes the full-length protein, including 3’UTR were replaced by human FN1 exons 1~46 in B-hFN1 mice. The promoter and 5’UTR region of the mouse gene are retained. The human FN1 expression is driven by endogenous mouse Fn1 promoter, while mouse Fn1 gene transcription and translation will be disrupted.

Verification:

• Human FN1 was exclusively detectable in homozygous B-hFN1 mice, but not in C57BL/6JNifdc mice. 
• Mouse Fn1 mRNA was only detected in wild-type mice, human FN1 mRNA was only detected in homozygous B-hFN1 mice.

Application:

• This product can be used to evaluate the efficacy and toxicity of drugs against breast cancer, nasopharyngeal cancer, thyroid cancer and other tumors with high expression of this target.

Gene targeting strategy for B-hFN1 mice. The exons 1~46 of mouse Fn1 gene that encodes the full-length protein, including 3’UTR were replaced by human FN1 exons 1~46 in B-hFN1 mice. The promoter and 5’UTR region of the mouse gene are retained. The human FN1 expression is driven by endogenous mouse Fn1 promoter, while mouse Fn1 gene transcription and translation will be disrupted.  

Western blot analysis of FN1 protein expression in homozygous B-hFN1 mice. Various tissue lysates were collected from wild-type C57BL/6JNifdc mice (+/+) and homozygous B-hFN1 mice (H/H), and then analyzed by western blot with anti-human FN1 antibody (CST, 26836S). 40 μg total proteins were loaded for western blotting analysis. Human FN1 was only detected in homozygous B-hFN1 mice.

Strain specific analysis of FN1 mRNA expression in wild-type C57BL/ 6JNifdc mice and B-hFN1 mice by RT-PCR. Liver RNA were isolated from wild-type C57BL/6JNifdc mice (+/+) and homozygous B-hFN1 mice (H/H), then cDNA libraries were synthesized by reverse transcription, followed by PCR with mouse or human FN1 primers. Mouse Fn1 mRNA was only detectable in wild-type mice. Human FN1 mRNA was exclusively detectable in homozygous B-hFN1 mice but not in wild-type mice.