• Collagen alpha-1(III) chain, also known as the alpha 1 chain of type III collagen, is a protein that in humans is encoded by the COL3A1 gene.  Three alpha 1 chains are required to form the type III collagen molecule which has a long triple-helical domain.  Type III collagen, an extracellular matrix protein, is synthesized by cells as a pre-procollagen.  It is found as a major structural component in hollow organs such as large blood vessels, uterus and bowel.  Other functions of type III collagen include interaction with platelets in the blood clotting cascade and it is also an important signalling molecule in would healing.
• Gene editing strategy: The exons 1-51 of mouse Col3a1 gene is replaced by human counterparts in B-hCOL3A1 mice. The promoter, 5’UTR and 3’UTR region of the mouse gene are also retained. The human COL3A1 expression is driven by endogenous mouse Col3a1 promoter, while mouse Col3a1 gene transcription and translation will be disrupted.
• mRNA expression analysis: Human COL3A1 mRNA was detectable in homozygous B-hCOL3A1 mice but not in wild-type mice.
• Protein expression analysis: Human COL3A1 was detectable only in skin from homozygous B-hCOL3A1 mice but not in wild-type mice.
• Application: This product is used for the immune and toxicological evaluation of recombinant human collagen implants and related disease drugs

Gene targeting strategy for B-hCOL3A1 mice. The exons 1-51 of mouse Col3a1 gene is replaced by human counterparts in B-hCOL3A1 mice. The promoter, 5’UTR and 3’UTR region of the mouse gene are also retained. The human COL3A1 expression is driven by endogenous mouse Col3a1 promoter, while mouse Col3a1 gene transcription and translation will be disrupted.

Strain specific analysis of COL3A1 mRNA expression in wild-type C57BL/6JNifdc mice and homozygous B-hCOL3A1 mice by RT-PCR. Skin RNA were isolated from wild-type C57BL/6JNifdc mice (+/+) and homozygous B-hCOL3A1 mice (H/H), then cDNA libraries were synthesized by reverse transcription, followed by PCR with mouse or human COL3A1 primers. Mouse Col3a1 mRNA was detectable in wild-type mice. Human COL3A1 mRNA was detectable in homozygous B-hCOL3A1 mice but not in wild-type mice.

Western blot analysis of COL3A1 protein expression in homozygous B-hCOL3A1 mice. Various tissue lysates were collected from wild-type C57BL/6 mice (+/+) and homozygous B-hCOL3A1 mice (H/H), and then analyzed by western blot with species-specific anti-hCOL3A1 antibody (Abcam, ab6310). 40 μg total proteins were loaded for western blotting analysis. Human COL3A1 was detectable only in skin from homozygous B-hCOL3A1 mice but not in wild-type mice.