Navigation Links
Some like it hot: The role of heat in sea lampreys' sex lives

'Is it hot in here or is it just you?' Clichd chat-up lines may serve some humans well, but other animals prefer more imaginative ways to captivate and attract potential suitors. Take, for example, the male sea lamprey, which will coax ovulating females into its nest by releasing enticing pheromones. Once comfortably in the nest, the male will then perform an interesting dance routine, rubbing the female's belly with a small bump of tissue on his back. Should the female be happy with what she sees and feels, the two will then spawn their gametes simultaneously. This unusual courtship routine is well characterised but no one is quite sure what role this bump, called rope tissue, plays in the proceedings. 'We thought it's just a structure that was used for some kind of mechanical stimulation that they needed to trigger the female to lay eggs', says Yu-Wen Chung-Davidson, from Michigan State University, USA, who has been studying lampreys for 10 years. However, she wasn't sure if this was the case, and so Chung-Davidson and her colleagues decided to investigate. They publish their findings in The Journal of Experimental Biology that rope tissue is a heat-generating secondary sexual trait -- the first of its kind ever identified

To begin her investigation, Chung-Davidson simply looked at the rope tissue under the microscope, and what she saw surprised her: 'It looked opaque, and it looked like fat to me.' Explaining her next step, she says, 'I happened to have tissues from various life stages of these lampreys and so I compared them and it's very interesting. When they are in the immature state, the male and females look more or less the same. But when I looked in the mature males and females, they were very different. So there's very obvious sexual dimorphism in their morphology and this part of their body.'

When Chung-Davidson delved deeper, looking at the slides of the rope tissue under a transmission electron microscope, she was again surprised. The cells weren't just normal white fat cells. She explains that white fats cells have a characteristic giant oil droplet whereas these cells clearly had several smaller droplets and were packed full of mitochondria (powerhouse organelles that produce energy). In fact, these fats cells looked remarkably similar to another, rare type of fat brown fat cells. To further characterise this fat, Chung-Davidson and her colleagues analysed what types of fatty acids and proteins were present in the cells. While the fatty acid profile looked remarkably similar to that of mammalian brown fat cells, the pattern of proteins varied a little.

All in all, however, the fat looked very similar to brown fat but it remained to be seen whether it had brown fat's defining trait the ability to produce heat. Chung-Davidson explains that this type of fat is usually found in mammals that need to maintain their own body temperature (unlike lampreys, whose body temperature varies with the environment). First the team looked for UCP-1, a protein that allows mitochondria to use fat to generate heat instead of energy they found that lampreys didn't express it but they did express UCP-2, a related protein. To directly test the thermogenic abilities of the rope tissue, Chung-Davidson implanted tiny probes into the rope tissue and some muscle tissue of sexually mature male lampreys. The team found that the rope temperature immediately rose by up to 0.3C when male lampreys encountered a female, with some getting hotter than others when encountering certain females. Whether they get hotter when more attracted and indeed what the role of this hot tissue is remain unknown-- regardless, perhaps lampreys could use the altered chat-up line: 'Is it hot in here or is it just me?'


Contact: Michaela Handel
The Company of Biologists

Related medicine news :

1. Malawi trial saves newborn lives
2. New NHCPS App, CertAlert+, Makes Health Care Providers’ Lives Much Easier
3. Austerity cuts to Spanish healthcare system are putting lives at risk
4. Smartphones, drones, to save lives in Malawi
5. Radioimmunotherapy could extend lives of advanced lymphoma patients
6. Partial livers from deceased donors saving the lives of infants
7. Merck for Mothers Supports UNICEF’s Efforts to Help Save Lives in South Africa
8. Kaufman Shows People With Diabetes How to Use New Technology to Improve Their Lives
9. New Emergency Stroke Treatments Can Save and Restore Lives if Patients Act Quickly and Call 911
10. Mercy's Digital Hospital Records Save Lives in Joplin
11. Mom+Social Highlights the Power of Social Media to Improve the Lives of Families and Communities Around the World
Post Your Comments:
(Date:11/26/2015)... ... November 26, 2015 , ... CognisantMD and Cambridge ... imaging in the Waterloo region. Using the Ocean Platform, family physicians can now ... their electronic medical record (EMR) without the need for redundant patient entry or ...
(Date:11/26/2015)... ... 2015 , ... Jobs in hospital medical laboratories and in the imaging field ... agency Aureus Medical Group . These fields, as well as travel ... for healthcare jobs through the company’s website, , The leading healthcare ...
(Date:11/26/2015)... Viejo, CA (PRWEB) , ... November 26, 2015 ... ... users a new set of retro-fused, self-animating trailer titles with ProTrailer: Vintage. This ... style options. These classically-influenced trailer titles work with any font, giving users limitless ...
(Date:11/25/2015)... ... November 25, 2015 , ... Additional breast cancers ... on mammography, according to a study published online in the journal Radiology. Researchers ... mammography may necessitate a change in treatment. , Breast MRI is the most ...
(Date:11/25/2015)... ... November 25, 2015 , ... Finnleo, a leader in the traditional and far-infrared ... traditional and far-infrared saunas. , For traditional saunas, Finnleo is offering ... sauna wood, and Finnleo uses only European Grade A Nordic White Spruce from sustainably ...
Breaking Medicine News(10 mins):
(Date:11/26/2015)... , 26 november 2015 AAIPharma ... de geplande investering aan van ten minste ... laboratoria en het mondiale hoofdkantoor in ... zal resulteren in extra kantoorruimte en extra ... de groeiende behoeften van de farmaceutische en ...
(Date:11/26/2015)... November 26, 2015 --> ... use SyMRI to find optimal contrast weighting of MRI ... and has signed a research agreement with SyntheticMR in order ... Using SyMRI, it is possible to generate multiple contrast images ... the patient has left, thus making it possible to both ...
(Date:11/26/2015)... , Nov. 26, 2015 Research ... addition of the "2016 Future Horizons and ... (TDM) Market: Supplier Shares, Country Segment Forecasts, Competitive ... --> --> ... analysis of the Japanese therapeutic drug monitoring market, ...
Breaking Medicine Technology: