Worm sperm stimulate ovulation

A protein that nematode sperm cells use for getting around also stimulates egg

maturation and ovulation in the worms, according to a report in March 16 Science.

Triggering ovulation with major sperm protein, or MSP, ensures that eggs aren’t

released at a time when there’s no sperm around to fertilize them, explains

coauthor David Greenstein of Vanderbilt University School of Medicine in

Nashville. “This is a mechanism to sense the availability of sperm,” he says.

“This blew our minds because [the sperm] use MSP to crawl around,” says

Greenstein. Sperm of the nematode Caenorhabditis elegans ooze around like amoebas

instead of swimming like, say, human sperm.

Sperm availability is not normally a problem for any particular C. elegans because

each worm has both male and female reproductive organs. But other nematodes have

separate sexes, which means that sperm aren’t always available.

Greenstein suggests that finding agents that interfere with MSP detection by

female tissues, and therefore with fertilization, could lead to drugs for

combating some parasitic intestinal worms in people and domestic animals.