Featured Research

from universities, journals, and other organizations

Mouse Calls During Courtship Help Search For Emotion-controlling Genes

Date:
April 3, 2008
Source:
Public Library of Science
Summary:
Scientists have long known that emotions and other personality traits and disorders run together in families. But finding which genes are most important in controlling emotions has proven difficult. Researchers have noted that male mice make high-frequency vocalizations during sexual interactions with female mice. These high-frequency calls are associated with approach behaviors, and with genes that control positive emotions. In the courtship phase, before mounting, males usually made simple whistles or modulated calls. After mounting the females, however, the males shifted to more complex "chirp-like" vocalizations. The male vocalizations increased in number and complexity as intensity increased.

Scientists have long known that emotions and other personality traits and disorders run together in families. But finding which genes are most important in controlling emotions has proven difficult. Humans and mice have similar numbers of genes, but mice are valuable because their genes can be deleted or added. Many researchers have begun to study mouse behaviors to try to link genes with complex behaviors.

A new study found that male mice make high-frequency vocalizations during sexual interactions with female mice. These high-frequency calls are associated with approach behaviours, and with genes that control positive emotions.

"This work has supported the theory, proposed by Jeffrey Burgdorf and Jaak Pansepp, that 50-kHz calls reflect positive affect in rats, and extended that theory to higher-frequency mouse calls," Wang said.

These high-frequency calls are inaudible to humans, but can be measured using special microphones and computer programs. The complex calls have "chirp-like" syllables and structure like bird songs. The number and density of different types of vocalizations and squeaks of male and female mice can be used to index the emotional responses of mice.

In the courtship phase, before mounting, males usually made simple whistles or modulated calls. After mounting the females, however, the males shifted to more complex "chirp-like" vocalizations. The male vocalizations increased in number and complexity as intensity increased.

The team of researchers include Haoran Wang, John Yeomans and Shuyin Liang at the University of Toronto, and Jeffrey Burgdorf at Northwestern University in Chicago.

Wang et al. found a marked reduction of male calls when single genes were deleted. In particular, they studied genes related to the transmitters, dopamine and acetylcholine, both of which are important for emotional expression in humans and rats. Two acetylcholine receptor gene deletions (for the M5 and M2 muscarinic receptors) reduced the number of calls. Furthermore, M2 and M5 receptor deletions changed the duration, frequency and bandwidth of the calls. However, M4 muscarinic receptor mutations (contributed by Jurgen Wess of NIH along with the M2 mice) and D2 dopamine receptor mutations were not found to change the number of calls. D2 dopamine receptor mutations changed the duration of the calls.

Furthermore, Wang found that, amphetamine, a street drug activating the brain dopamine system, can induce "chirp-like" calls at very low doses, indicating a role for dopamine. However, this induction was lost in male mice lacking M5 receptor genes, known to be important for activating dopamine neurons.

These findings provide a new method for screening emotion genes, and for developing drugs for controlling emotions, drug abuse and mood disorders.

Journal reference: Wang H, Liang S, Burgdorf J, Wess J, Yeomans J (2008) Ultrasonic Vocalizations Induced by Sex and Amphetamine in M2, M4, M5 Muscarinic and D2 Dopamine Receptor Knockout Mice. PLoS One 3(4): e1893. doi:10.1371/journal.pone.0001893


Story Source:

The above story is based on materials provided by Public Library of Science. Note: Materials may be edited for content and length.


Cite This Page:

Public Library of Science. "Mouse Calls During Courtship Help Search For Emotion-controlling Genes." ScienceDaily. ScienceDaily, 3 April 2008. <www.sciencedaily.com/releases/2008/04/080402071547.htm>.
Public Library of Science. (2008, April 3). Mouse Calls During Courtship Help Search For Emotion-controlling Genes. ScienceDaily. Retrieved October 20, 2014 from www.sciencedaily.com/releases/2008/04/080402071547.htm
Public Library of Science. "Mouse Calls During Courtship Help Search For Emotion-controlling Genes." ScienceDaily. www.sciencedaily.com/releases/2008/04/080402071547.htm (accessed October 20, 2014).

Share This



More Plants & Animals News

Monday, October 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Rare Lion Cubs Make Debut at Belgrade Zoo

Raw: Rare Lion Cubs Make Debut at Belgrade Zoo

AP (Oct. 17, 2014) Two white lion cubs were born in Belgrade zoo three weeks ago. White lions are a rare mutation of a species found in South Africa and some cultures consider them divine. (Oct. 17) Video provided by AP
Powered by NewsLook.com
The Best Foods To Boost Your Mood

The Best Foods To Boost Your Mood

Buzz60 (Oct. 17, 2014) Feeling down? Reach for the refrigerator, not the medicine cabinet! TC Newman (@PurpleTCNewman) shares some of the best foods to boost your mood. Video provided by Buzz60
Powered by NewsLook.com
Sweet Times for Hard Cider Makers

Sweet Times for Hard Cider Makers

AP (Oct. 16, 2014) With hard cider making a hardcore comeback across the country, craft makers are trying to keep up with demand and apple growers are tapping a juicy new revenue stream. (Oct. 16) Video provided by AP
Powered by NewsLook.com
Meet Garfi the Angry Cat

Meet Garfi the Angry Cat

Buzz60 (Oct. 16, 2014) Garfi is one frowny, feisty feline - downright angry! Ko Im (@koimtv) introduces us to the latest animal celebrity taking over the Internet. You can follow more of Garfi's adventures on Twitter (@MeetGarfi) and Facebook (Garfi). Video provided by Buzz60
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins