Cell-death sex differences

A protein involved in Drosophila courtship produces sexually dimorphic neural circuitry in the fly brain, according to a letter in this week's Nature. This protein establishes a circuit of neurons in males that feeds into brain areas known to be involved in male courting behaviors. Corresponding neurons in females, which lack this protein, die through programmed cell death, the authors say.

"They show very clearly that cell death seems to be involved in at least some aspects of a sexually dimorphic nervous system," said Stephen Goodwin of the University of Glasgow in Scotland, who was not involved in the study.

The gene fruitless (fru) is transcribed in both females and males but then is spliced differently in each sex. Functional Fru protein is translated only in males, first author Ken-ichi Kimura of Hokkaido University of Education in Iwamizawa, Japan, told The Scientist in an Email.

Recent work established that Fru ...