Navigation Links
Geneticists discover genes that make fruit fly hybrids sterile

While hybrids -- the result of the mating of two different species -- may offer interesting and beneficial traits, they are usually sterile or unable to survive. For example, a mule, the result of the mating of a horse and a donkey, is sterile.

Now, Cornell researchers have made the first identification of a pair of genes in any species that are responsible for problems unique to hybrids. Specifically, the researchers have found two genes from two fruit fly species (Drosophila melanogaster and D. simulans) that interfere with each other, thereby preventing the production of male offspring.

The finding may eventually shed light on what causes lethality or sterility in hybrids in general and, in a larger sense, offers clues to how species evolve from common ancestors.

The research, published in the Nov. 24 issue of Science, focuses on a rarely occurring mutation in a D. melanogaster gene called "Hmr" (Hybrid male rescue) and a similar mutation in a D. simulans gene called "Lhr" (Lethal hybrid rescue) that make these genes nonfunctional. When either of these genes is "turned off" and then crossed with the other fruit fly species, the males survive.

"We have found the first example of two genes that interact to cause lethality in a species hybrid," said the paper's senior author, Daniel Barbash, assistant professor in Cornell's Department of Molecular Biology and Genetics.

The finding supports the Dobzhansky-Muller model, a theory from the 1930s that suggests hybrid incompatibilities (such as death or sterility) are caused by genes that have evolved from a common ancestor but diverged in each of the species. More specifically, in the common ancestor, these genes may have worked perfectly well together. But, as each gene evolved in its own species, it began to code for proteins that no longer work in the other species.

In this case, when genes from each species were compared with each other, the Hmr gene in D. melanogaster and the Lhr gene in D. simulans each evolved much faster than most other genes and diverged due to natural selection, a genetic change due to a pressure that benefits the survival of a species. The researchers would like to learn what these genes normally do within their species in order to understand why they are evolving so fast.

The Dobzhansky-Muller model also proposes that these evolved genes depend on each other to cause hybrid incompatibilities.

However, when Barbash and his colleagues cloned each gene and inserted an Lhr gene from D. simulans into D. melanogaster, the two genes did not interfere with each other in the engineered D. melanogaster strain even though the Lhr and Hmr genes interfere with each other in hybrids.

"This tells us there must be other things involved in the hybrid" that impacts the incompatible pairing of these genes, said Barbash. In future work the researchers hope to determine whether the hybrids die because of additional genes like Hmr and Lhr, or because of more subtle differences between the chromosomes of these two species.


'"/>

Source:Cornell University News Service


Related biology news :

1. UAB scientists discover the origin of a mysterious physical force
2. Researchers discover way to make cells in the eye sensitive to light
3. Protein discovery could unlock the secret to better TB treatment
4. Newly-discovered class of genes determines ?and restricts ?stem cell fate
5. Newly discovered virus linked to childhood lung disorders and Kawasaki disease
6. Purdue proves concept of using nano-materials for drug discovery
7. Scientists discover the cellular roots of graying hair
8. Researchers discover molecule that causes secondary stroke
9. Scientists discover unique microbe in Californias largest lake
10. New protein discovered by Hebrew University researchers
11. UCSD discovery may help extend life of natural pesticide
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:6/21/2016)... , June 21, 2016 NuData Security announced ... new role of principal product architect and that ... director of customer development. Both will report directly ... officer. The moves reflect NuData,s strategic growth in ... to high customer demand and customer focus values. ...
(Date:6/9/2016)... June 9, 2016 Paris ... Teleste,s video security solution to ensure the safety of people ... during the major tournament Teleste, an international ... and services, announced today that its video security solution will ... to back up public safety across the country. The system ...
(Date:6/2/2016)... , June 2, 2016 Perimeter ... Platforms, Unmanned Systems, Physical Infrastructure, Support & Other Service  ... visiongain offers comprehensive analysis of the global ... market will generate revenues of $17.98 billion in 2016. ... DVTEL Inc, a leader in software and hardware technologies ...
Breaking Biology News(10 mins):
(Date:6/24/2016)... ... 2016 , ... While the majority of commercial spectrophotometers and fluorometers use the ... models are higher end machines that use the more unconventional z-dimension of 20mm. ... the bottom of the cuvette holder. , FireflySci has developed several Agilent flow ...
(Date:6/23/2016)... ... June 23, 2016 , ... UAS LifeSciences, one of ... their brand, UP4™ Probiotics, into Target stores nationwide. The company, which has been ... Target to its list of well-respected retailers. This list includes such fine stores ...
(Date:6/23/2016)... SPRING, Md. , June 23, 2016 A ... collected from the crime scene to track the criminal down. ... and the U.S. Food and Drug Administration (FDA) uses DNA ... Sound far-fetched? It,s not. The ... genome sequencing to support investigations of foodborne illnesses. Put as ...
(Date:6/23/2016)... , June 23, 2016  The Prostate Cancer Foundation (PCF) is ... treatments and faster cures for prostate cancer. Members of the Class of 2016 ... countries. Read More About the Class of 2016 PCF ... ... ...
Breaking Biology Technology: