Male and female sex cell determination requires lifelong maintenance and protection

May 22, 2014

The way in which the sex of an organism is determined may require lifelong maintenance, finds new research from the University of Minnesota. According to the study published today in the journal Developmental Cell, sex-specific transcription factors perform lifelong work to maintain sexual determination and protect against reprogramming of cells from one sex to the other.

Previous research at the University of Minnesota's Department of Genetics, Cell Biology, and Development showed is not permanent. Using a mouse model, researchers found the sex of gonadal cells – those found in the ovaries or testes – require maintenance throughout life. This research also showed loss of a single transcription factor can result in the transformation of male cells into female cells.

"DMRT1 in the testis and FOXL2 in the ovary have been identified as key responsible for maintaining sexual differentiation. What we asked in this study was how the cells maintain and why their sex determination requires continuous protection," said David Zarkower, Ph.D., principal author and director of the Developmental Biology Center at the University of Minnesota.

Zarkower's research team took a closer look at DMRT1 and determined it partners with the male fetal sex determination gene called Sox9 to maintain male sexual determination after birth in a . Part of that work includes silencing genes normally involved in the female fetal sex determination process. This discovery indicates lifelong sex determination maintenance requires a process related to prenatal sex determination.

Another notable discovery is DMRT1's ability to limit retinoic acid (RA) signaling, preventing RA from activating genes normally involved in female sex determination and female organ development.

"While RA signaling between cells is absolutely required for sperm production and male fertility, we found that RA also has a dark side. If DMRT1 is not there to act as a guardian of maleness, RA has the potential to activate genes driving male-to-female transdifferentiation," said Zarkower. "This shows cell signaling can transform the identities of the very that use it from male to female. We think other cell types may also require similar mechanisms allowing them to use critical signaling molecules without becoming reprogrammed."

Explore further: Researchers discover gene required to maintain male sex throughout life

Related Stories

A guardian gene for female sex

January 31, 2014

Researchers at INRA, France, have just uncovered one of the major genes responsible for female differentiation: FOXL2. During normal development, the formation of testes or ovaries in a foetus depends on the presence or absence ...

An embryo that is neither male nor female

January 3, 2013

So, is it a girl or a boy? This is the first question parents ask at the birth of an infant. Though the answer is obvious, the mechanism of sex determination is much less so. Researchers at the University of Geneva (UNIGE) ...

Scientists identify key event for sex determination

November 27, 2012

Scientists at the Institute of Molecular Biology (IMB) in Mainz have identified a protein essential for initiating the development of male sex organs. Loss of the gene Gadd45g results in complete sex reversal of male mice, ...

Recommended for you

Humans found to be playing a role in spread of ranavirus

September 28, 2016

(Phys.org)—A team of researchers with the Zoological Society of London, Queen Mary University of London, University College London and Herpetofauna Consultants International and assisted by citizen scientists involved with ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.