Navigation Links
Sperm can count
Date:3/7/2012

This release is available in German.

Sperm have only one aim: to find the egg. The egg supports the sperm in their quest by emitting attractants. Calcium ions determine the beating pattern of the sperm tail which enables the sperm to move. Together with colleagues from the Max Planck Institute for the Physics of Complex Systems in Dresden and the University of Gttingen, scientists from the caesar research centre in Bonn, an institute of the Max Planck Society, have discovered that sperm only react to changes in calcium concentration but not to the calcium concentration itself. Probably sperm make this calculation so that they remain capable of manoeuvring even in the presence of high calcium concentrations.

The swimming path on which sperm follow the mating call of the egg, varies according to species. Sperm in particular those of marine species swim along convoluted paths in a chemical concentration gradient. Their swimming style is controlled by the calcium ions in the sperm tail. It was previously believed that in high calcium concentrations, the sperm tails make asymmetrical, whip-like movements and their swimming path is very curved, while in low calcium concentrations, the tails beat symmetrically and the sperm swim on a straight line. The alternation of high and low calcium concentrations was thought to propel sperm along spiral-shaped swimming paths. However, this simple model was repudiated by experiments on freely-swimming sperm and presented researchers with something of a mystery.

The scientists have now succeeded in solving this mystery. Using ingenious stroboscopic laser illumination similar to that used in discotheques project leader Luis Alvarez was able to trace the movement of a sperm in detail, and simultaneously measure the changes in the calcium concentration. The result was astonishing: the sperm tail only reacted to the time derivative of the calcium concentration and the absolute concentration was of little relevance. To put it simply: sperm can count! Exactly how they do this is unclear. The caesar scientists suspect that sperm bind calcium ions with the help of two proteins and in thereby create a "chemical derivative", so to speak.

But why do sperm carry out this complicated kind of calculation that we first encounter at upper secondary school level? The concentration of the attractants and, therefore also, the calcium concentration in the sperm is very high near the egg. The mathematical trick probably enables the sperm to be able to react even in the presence of such high calcium concentrations.

Apart from calcium, many other messenger substances control cell functions. Is it possible, therefore, that cells also carry out complex chemical calculations involving other messenger substances? The Bonn scientists would like to investigate this important question next.


'/>"/>

Contact: Luis Alvarez, Ph.D.
luis.alvarez@caesar.de
49-228-965-6354
Max-Planck-Gesellschaft
Source:Eurekalert

Related biology news :

1. Low sperm count may be associated with prenatal testosterone excess
2. Proteins in sperm unlock understanding of male infertility says new study
3. The more promiscuous the female, the speedier the sperm
4. CSHL scientists discover how companion cells to sperm protect them from genetic damage
5. The egg makes sure that sperm dont get too old
6. Spread your sperm the smart way
7. ESHREs workshop on freezing of human sperm, eggs and embryos in Athens
8. MMS and NOAA scientists study prey of Gulf of Mexico sperm whales
9. Molecular study could push back angiosperm origins
10. Females shut down male-male sperm competition in leafcutter ants
11. UT Southwestern researchers use novel sperm stem-cell technique to produce genetically modified rats
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:10/4/2017)... 2017  GCE Solutions, a global clinical research organization (CRO), announces ... solution on October 4, 2017. Shadow is designed to assist medical ... policy 0070 of the European Medicines Agency (EMA) in meeting the ... ... ...
(Date:7/20/2017)... DAL ) customers now can use fingerprints instead of their ... (DCA). ... launches biometrics to board aircraft at Reagan Washington National Airport ... Delta,s biometric boarding pass experience that launched in May at ... process to allow eligible Delta SkyMiles Members who are enrolled in CLEAR ...
(Date:6/14/2017)... , June 15, 2017  IBM (NYSE: IBM ) is ... tech event dedicated to developing collaboration between startups and global ... June 15-17. During the event, nine startups will showcase the ... in various industries. France ... international market, with a 30 percent increase in the number ...
Breaking Biology News(10 mins):
(Date:10/12/2017)... (PRWEB) , ... October 12, 2017 , ... ... in Vilnius, Lithuania, announced today that they have entered into a multiyear collaboration ... to provide CRISPR researchers with additional tools for gene editing across all applications. ...
(Date:10/11/2017)... ... October 11, 2017 , ... ... President Andi Purple announced Dr. Suneel I. Sheikh, the co-founder, CEO and chief ... ), Inc. has been selected for membership in ARCS Alumni Hall of ...
(Date:10/11/2017)... INDIANAPOLIS , Oct. 11, 2017  VMS BioMarketing, a ... of a nationwide oncology Clinical Nurse Educator (CNE) network, which ... growing need for communication among health care professionals to enhance ... physicians, nurses, office staff, and other health care professionals to ... for breast cancer. ...
(Date:10/10/2017)... DIEGO, CALIF. (PRWEB) , ... October 10, 2017 , ... ... as part of its corporate rebranding initiative announced today. The bold new look ... its reach, as the company moves into a significant growth period. , It will ...
Breaking Biology Technology: