Navigation Links
Squid pheromone sparks extreme aggression on contact
Date:2/10/2011

When male squid come into contact with a chemical found on the outside of eggs laid by females, they instantly go from swimming along calmly and minding their own business to a state of extreme aggression, according to a new report published online on February 10 in Current Biology, a Cell Press publication. After just a touch of an egg, males will often fight vigorously with other males in an attempt to gain preferred access to mates, even when females aren't around.

The researchers believe that the findings represent the first detailed evidence of an aggression-inducing contact pheromone in any aquatic animal.

"The identification of this pheromone as a key component of this signaling system is highly unusual because the male squids need only to contact these protein molecules to initiate the complex cascade of behaviors that we term aggressive fighting," said Roger Hanlon of the Marine Biological Laboratory at Woods Hole.

That's particularly notable because aggression is generally thought to be a rather complex process, involving some combination of neural, hormonal, physiological, and psychological stimuli. "Here we find what appears to be a strong and seemingly direct stimulus from certain protein molecules," Hanlon says.

Squid are highly advanced marine invertebrates with a complex mating system rivaling that of vertebrates. The loliginid squid that were the focus of the current study live for about a year, with most mating and egg laying occurring in the spring, when the squids migrate from deeper offshore waters to shallower waters along the coast from North Carolina to southern Maine. Females typically mate multiple times, and males compete fiercely for the opportunity to mate. When males see eggs on the seafloor, they will typically approach and, upon touching them, immediately escalate into intense physical fighting with any nearby males.

Hanlon and his colleagues have now traced that reaction to a single protein pheromone that is produced in the female reproductive tract and embedded in the outer surface of the egg capsules. In controlled behavioral experiments, the researchers found that males would react aggressively just as they do upon touching an egg after being presented with the purified form of the protein, known as Loligo β-microseminoprotein.

The laboratory experiments show that whichever male touches the eggs first becomes aggressive faster than those that reach the eggs later. That earlier aggression leads those males to achieve greater dominance. They also win most (but not all) of the matings and most (but not all) of the fertilizations, Hanlon says.

Interestingly, the microseminoprotein under study belongs to a family of proteins found in vertebrates including humans, Hanlon says. The proteins are generally found in reproductive glands and are at high levels in human and mouse seminal fluid.

"The functions of microseminoproteins in vertebrates have not been determined, but our findings in squids may inspire other researchers to consider similar functions in higher vertebrates," he says.


'/>"/>

Contact: Elisabeth Lyons
elyons@cell.com
617-386-2121
Cell Press
Source:Eurekalert

Related biology news :

1. Squid studies provide valuable insights into hearing mechanisms
2. Habitat of elusive Northern squid documented by researcher
3. URI researcher sheds light on man-eating squid; finds them timid, nonthreatening
4. URI researcher sheds light on man-eating squid; finds them timid, non-threatening
5. Ocean acidification from CO2 emissions will cause physiological impairment to jumbo squid
6. Chloride increases response to pheromones and odors in mouse sensory neurons
7. Grant sparks hope for incurable disease
8. Sparks to receive Liebig Medal from International Union of Soil Sciences
9. Prolonged stress sparks ER to release calcium stores and induce cell death in aging-related diseases
10. A thirst for blood sparks toxic algal blooms
11. Volcanoes may have provided sparks and chemistry for first life
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/5/2017)... -- The Allen Institute for Cell Science today announces the ... and dynamic digital window into the human cell. The ... of deep learning to create predictive models of cell ... growing suite of powerful tools. The Allen Cell Explorer ... available resources created and shared by the Allen Institute ...
(Date:4/5/2017)... April 4, 2017 KEY FINDINGS ... expand at a CAGR of 25.76% during the forecast ... the primary factor for the growth of the stem ... https://www.reportbuyer.com/product/4807905/ MARKET INSIGHTS The global stem cell ... application, and geography. The stem cell market of the ...
(Date:4/3/2017)... 3, 2017  Data captured by IsoCode, ... detected a statistically significant association between the ... treatment and objective response of cancer patients ... predict whether cancer patients will respond to ... well as to improve both pre-infusion potency testing ...
Breaking Biology News(10 mins):
(Date:4/26/2017)... ... April 26, 2017 , ... Looking ... team-building and cooking events company, offers one-of-a-kind gifts, ranging from gourmet cooking experiences ... California cuisine, and guests leave inspired with new cooking tips and techniques, thanks ...
(Date:4/26/2017)... ... April 25, 2017 , ... LABS, Inc. (LABS) announced in December ... its extensive test menu: Nucleic Acid Testing (NAT) for ZIKV; and Enzyme Immunoassays (EIAs) ... to offer NAT screening for blood donors under an Investigational New Drug (IND) study ...
(Date:4/26/2017)... ... April 26, 2017 , ... As the call for ... industry stakeholders, the discussion surrounding the topic will continue at WEDI 2017- Driving ... Los Angeles, Calif. Hosted by the Workgroup for Electronic Data Interchange (WEDI), the ...
(Date:4/25/2017)... ... 25, 2017 , ... Franz Inc ., an early ... and market leader for Semantic Graph Database technology, today announced ... most effective system for developing and deploying applications to solve the challenges developers ...
Breaking Biology Technology: