Biological sex is typically understood in binary terms: male and female. However, there are many examples of animals that are able to modify sex-typical biological and behavioral features and even change sex. A new study, which appears in the journal Current Biology, identifies a genetic switch in brain cells that can toggle between sex-specific states when necessary, findings that question the idea of sex as a fixed property.
The research was conducted in C. elegans, a microscopic roundworm that has been used in labs for decades to understand the nervous system. Many of the discoveries made using C. elegans apply throughout the animal kingdom and this research has led to a broader understanding of human biology. C. elegans is the only animal whose nervous system has been completely mapped, providing a wiring diagram - or connectome - that is helping researchers understand how brain circuits integrate information, make decisions, and control behavior.
There are two sexes of C. elegans, males and hermaphrodites. Though the hermaphrodites are able to self-fertilize, they are also mating partners for males, and are considered to be modified females. A single gene, TRA-1, determines the sex of these roundworms. If a developing worm has two X chromosomes, this gene is activated and the worm will develop into a female. If there is only one X chromosome, TRA-1 is inactivated, causing the worm to become a male.
The new study shows that the TRA-1 gene doesn't go completely silent in males, as had been previously thought. Instead, it can go into action when circumstances compel males to act more like females. Typically, C. elegans males prefer searching for mates over eating, in part because they can't smell food as well as females do. But if a male goes too long without eating, it will dial up its ability to detect food and acts more like a female. The new research shows that TRA-1 is necessary for this switch, and without it hungry males can't enhance their sense of smell and stay locked in the default, food-insensitive mate-searching mode. TRA-1 does the same job in juvenile males - it activates efficient food detection in males that are too young to search for mates.
"These findings indicate that, at the molecular level, sex isn't binary or static, but rather dynamic and flexible," said the senior author. "The new results suggest that aspects of the male nervous system might transiently take on a female 'state,' allowing male behavior to be flexible according to internal and external conditions."
A separate study appearing Current Biology by a team of collaborating researchers further describes the complex molecular mechanism by which TRA-1 is controlled by sex chromosomes and other cues.
https://www.urmc.rochester.edu/del-monte-neuroscience/neuroscience-blog/august-2020-1/study-biology-blurs-line-between-sexes-behaviors.aspx
https://www.cell.com/current-biology/fulltext/S0960-9822(20)30938-6
https://www.cell.com/current-biology/fulltext/S0960-9822(20)30997-0
http://sciencemission.com/site/index.php?page=news&type=view&id=publications%2Frapid-effects-of&filter=22
http://sciencemission.com/site/index.php?page=news&type=view&id=publications%2Fdynamic-non-binary&filter=22
Switch in the worm brain to change the sex and behavior
- 1,112 views
- Added
Edited
Latest News
New origin of deep brain waves
By newseditor
Posted 17 Apr
Starving cells hijack prote…
By newseditor
Posted 17 Apr
Miniature battery-free epid…
By newseditor
Posted 17 Apr
Molecular causes of differe…
By newseditor
Posted 16 Apr
Cell's 'garbage disposal' h…
By newseditor
Posted 16 Apr
Other Top Stories
Mapping ketamine's effects on brain
Read more
Cell-type-specific genetic risk contributes to distinct stages of A…
Read more
Hot hatha yoga potent antidepressant in a clinical trial
Read more
How bone marrow peripheral nerves promote hematopoietic and vascula…
Read more
Finding biomarker for inflammatory bowel disease using reverse meta…
Read more
Protocols
MemPrep, a new technology f…
By newseditor
Posted 08 Apr
A tangible method to assess…
By newseditor
Posted 08 Apr
Stem cell-derived vessels-o…
By newseditor
Posted 06 Apr
Single-cell biclustering fo…
By newseditor
Posted 01 Apr
Modular dual-color BiAD sen…
By newseditor
Posted 31 Mar
Publications
The immunobiology of herpes…
By newseditor
Posted 17 Apr
Circulating microbiome DNA…
By newseditor
Posted 17 Apr
Spindle oscillations in com…
By newseditor
Posted 17 Apr
Oligodendroglial macroautop…
By newseditor
Posted 17 Apr
COPII with ALG2 and ESCRTs…
By newseditor
Posted 17 Apr
Presentations
Hydrogels in Drug Delivery
By newseditor
Posted 12 Apr
Lipids
By newseditor
Posted 31 Dec
Cell biology of carbohydrat…
By newseditor
Posted 29 Nov
RNA interference (RNAi)
By newseditor
Posted 23 Oct
RNA structure and functions
By newseditor
Posted 19 Oct
Posters
A chemical biology/modular…
By newseditor
Posted 22 Aug
Single-molecule covalent ma…
By newseditor
Posted 04 Jul
ASCO-2020-HEALTH SERVICES R…
By newseditor
Posted 23 Mar
ASCO-2020-HEAD AND NECK CANCER
By newseditor
Posted 23 Mar
ASCO-2020-GENITOURINARY CAN…
By newseditor
Posted 23 Mar