Researchers clone key sperm-binding proteins

Mar 17, 2009
New treatments for infertility could be closer to reality, thanks to a discovery from scientists at the University of Montreal and Maisonneuve-Rosemont Hospital Research Center. According to a study published in the journal Molecular Human Reproduction, the researchers have become the first to clone, produce and purify a protein important for sperm maturation, termed Binder of Sperm, which may have implications for both fertility treatments and new methods of male contraception. Credit: University of Montreal and Maisonneuve-Rosemont Hospital Research Center

New treatments for infertility could be closer to reality, thanks to a discovery from scientists at the Université de Montréal and Maisonneuve-Rosemont Hospital Research Centre. According to a study published in the journal Molecular Human Reproduction, the researchers have become the first to clone, produce and purify a protein important for sperm maturation, termed Binder of Sperm (BSP), which may have implications for both fertility treatments and new methods of male contraception.

"We have previously isolated and characterized BSPs from many species, such as bulls and boars," says Dr. Puttaswamy Manjunath, senior author and a professor in the departments of medicine and of biochemistry at the Université de Montréal and a member of the Maisonneuve-Rosemont Hospital Research Centre.

"We know from these studies that if this protein is missing or defective in these species, fertility is compromised. We believe that BSP is equally important in humans."

An elusive protein

Dr. Manjunath and colleagues have tried to isolate human BSPs for more than 10 years. In most mammals, these proteins are typically produced by the seminal vesicles and added to at ejaculation. Yet this is not the case for humans, primates and rodents. According to Dr.Manjunath and his team, these species produce small amounts of BSPs only in the epididymis, a duct that connects the testes to the urethra.

"For a few years, we were looking in the wrong place," says Dr. Manjunath. "In addition, the minute quantities of BSP produced in humans has made it impossible to isolate and characterize."

Cloning leads to purification

Dr. Manjunath and his team went back to the basics. Using molecular biology technique they cloned the gene (DNA) that encodes human BSP. Through cloning, they were able to produce and purify this protein.

"After considerable troubleshooting, we were able to produce functional human BSP. Our next steps are to confirm its biological role in human fertility," says Dr. Manjunath.

Role of BSPs in other animals

Following ejaculation, sperm undergo a complex series of modifications inside the female reproductive tract. The changes sperm undergo during this process include redistribution of surface proteins, loss of sperm membrane lipids and increased sperm movement. A family of sperm-binding proteins (BSPs) secreted by the seminal vesicles has been shown to be essential for sperm maturation in female reproductive tracts of cows, sheep, pigs and other hoofed animals.

More information: The article, "Recombinant expression and affinity purification of a novel epididymal human sperm-binding proteins, BSPH1," was authored by Université of Montreal and Maisonneuve-Rosemont Hospital Research Center researchers Jasmine Lefebvre, Guy Boileau and Puttaswamy Manjunath.
www.oxfordjournals.org/our_jou… r_authors/index.html

Source: University of Montreal (news : web)

Explore further: Muscular dystrophy: Repair the muscles, not the genetic defect

add to favorites email to friend print save as pdf

Related Stories

Scientists discover gene responsible for brain's aging

Jan 16, 2009

Will scientists one day be able to slow the aging of the brain and prevent diseases such as Alzheimer's and Parkinson's? Absolutely - once the genetic coding associated with neuronal degeneration has been unraveled.

Recommended for you

Cellular protein may be key to longevity

9 hours ago

Researchers have found that levels of a regulatory protein called ATF4, and the corresponding levels of the molecules whose expression it controls, are elevated in the livers of mice exposed to multiple interventions ...

Gut bacteria tire out T cells

12 hours ago

Leaky intestines may cripple bacteria-fighting immune cells in patients with a rare hereditary disease, according to a study by researchers in Lausanne, Switzerland. The study, published in The Journal of Experimental Me ...

T-bet tackles hepatitis

12 hours ago

A single protein may tip the balance between ridding the body of a dangerous virus and enduring life-long chronic infection, according to a report appearing in The Journal of Experimental Medicine.

User comments : 0