News release

News Release Archive

Office of External Affairs

Mission magazine

Vital Signs

University page

Key blood-clotting factor found in zebrafish model

Scientists here have found the first evidence of a key blood-clotting agent, factor VII, in zebrafish. The finding by researchers at The University of Texas Health Science Center at San Antonio (UTHSC) further establishes the credibility of the zebrafish as a relevant model for studying human blood clotting.

“It is critical to show that the clotting cascade in zebrafish is very similar to human clotting so that zebrafish studies will have clinical relevance,” said Pudur Jagadeeswaran, Ph.D., associate professor of cellular and structural biology at UTHSC. The finding is reported in the July 17 online posting of Proceedings of the National Academy of Sciences at

Scientists theorized the existence of zebrafish factor VII for more than three decades. Dr. Russell F. Doolittle, research professor at The University of California, San Diego, first proposed the idea in the 1960s. Dr. Jagadeeswaran’s research team used recombinant DNA technology to create a zebrafish factor VII deficiency plasma, a substance that will not clot because factor VII is missing. The team repeated the experiment with a human factor VII deficiency plasma.

“This is a credible coagulation-initiation model,” Dr. Jagadeeswaran said. “Such studies could be important in development of new stroke-prevention drugs.”

Dr. Jagadeeswaran is one of 30 zebrafish researchers nationwide who will convene at UTHSC on July 26 and 27 for the Texas Zebrafish Development and Genetics Meeting.

Reporters: Side-by-side figures comparing factor VII in zebrafish and humans are available.

Contact: Will Sansom