Search This Blog

Tuesday, August 25, 2009

The honeybee genome:implications for an understanding of human behavior

A very interesting series of videos concerning the Honeybee genome can be viewed at the
nature.com website. To watch these videos please click on the following link:
http://www.nature.com/nature/videoarchive/honeybee/index.html

What is a genome you ask?
In classical genetics, the genome of most mammals refers to a full set of chromosomes or genes in a reproductive cell.In humans the gamete of the male and female join to form and embryo and then a fetus.

Why is it important to understand the honeybee genome?

"The Western honeybee, Apis mellifera, is a key model for social behavior and is essential to agriculture and global ecology because of its pollination activity. There are striking differences in the size of gene families in the honeybee genome relative to other sequenced genomes for several important protein and domain families. These differences, which involve both larger and smaller gene numbers, as well as other novel features of the honeybee genome,have been suggestively related to the social lifestyle of the honeybee."

"Honeybees are known as paragons of sociality, living in societies that rival human societies in complexity and cohesion. Honeybees are eu-social, which means their colony’s population is differentiated into queens that produce offspring and non-reproductive altruistic workers that communally gather and process food, care for young, build nests,and defend their hive.Social evolution endowed honeybees with impressive traits. Queens and workers come from the same genome, but queens—usually one per colony—have 10 times the life span of workers (typically queens live for several years), lay up to 2000 eggs per day,and store sperm for years without losing viability.Workers, numbering tens of thousands per colony,display sophisticated cognitive abilities, despite abrain containing only 1 million neurons, which is five orders of magnitude less than the human brain.Worker bees can learn to associate a flower’s color,shape, scent, or location with a food reward, thereby increasing the efficiency with which they gather nectar and pollen. Worker bees can even learn abstract concepts such as “same” and “different,” which presumably also increases their ability to home in on the most profitable flower patches. Honeybees that find a good source of food return to the hive and communicate their discovery with a “dance language,” the only known nonprimate symbolic language, in which information regarding the location of a food source is transmitted from a “finder” bee to others within the hive."

"Honeybees benefit human-kind in exceptionally broad ways. In agriculture, honey-bees are the most important pollinators of food and fiber crops, with a value of about $15 billion dollars annually in the United States alone. Of course, they also produce honey. In biology and biomedicine,honeybees are popular model research organisms in diverse areas including allergic disease, develop-ment, gerontology, neuroscience, social behavior,and venom toxicology. However, honeybees are also threatened by human activity, perishing due to insecticides that indiscriminately may kill both pests and beneficial insects, and exotic parasitic mites vectored around the world by human commerce. The sequencing of the genome of the Western honey-bee, A. mellifera , was carried out in order to advance basic biology and applied apiculture."

"Population genetic analyses based on the honeybee genome have generated exciting new insights into the longstanding controversy of whether Africanized bees (“killer bees,”Apis scutellata) spread throughout the New World via hybridization or
displacement The answer is both! (Hybridization means the act of mixing different species or varieties of animals or plants and thus to produce hybrids; From what I have read on the internet, displacement seems to refer to act where the genes of one species replace the genes in another species through reproduction due to interbreeding.In the case of honeybees and african killer bees the genes of the african bees became dominant in African honey bees and this caused a hybrid of bee to develop, the african killer bee)."

"Africanized honeybees were introduced to Brazil from Africa in 1956 in order to breed a strain more suited for the tropical climate. The plan was to breed out the aggressiveness of A. scutellata before releasing the bees, but they were accidentally released before this could happen. Africanized bees spread throughout the New World, reaching the United States in 1990. This spread of Africanized honeybees has been one of the most spectacular examples of abiological invasion."

"Analyses of the honeybee genome reveal that this biological invasion has involved extensive hybridization with European subspecies, but the genomes of some subspecies appear to be more resistant to domination than others.It will be fascinating to learn why these two subspecies show different “susceptibilities” to Africanization, and what this might mean for the genetics of aggressive behavior."

"Relative to the fruitfly and mosquito, honeybees show a remarkable reduction in the size of gene families associated with the detoxification of harmful chemicals encountered in the environment. Honeybees also show a similar reduction in the size of gene families that encode components of the immune system. Why this is so is a mystery, especially since life in a densely populated beehive would seem to put bees at special risk for environmental toxins, pathogens, and parasites.Perhaps this is why honey bees are extremely vulnerable to many types of insecticides and have sufferedmajor population losses in some agricultural regionsof the world, including the recent reports of devastating losses due to Colony Collapse Disorder. On the other hand, it appears that bee social evolution hasalso led to novel behavioral mechanisms of protection, such as the ability of some “nurse bees” to detect and remove diseased larvae from the hive, and the collection by foragers of plant-produced resin swith antimicrobial activity that are used to coat the walls of the beehive."

"As these results illustrate, the sequencing of the honeybee genome is expected to usherin a bright era of bee research for the benefitof agriculture, biological investigations, and human health."

source: http://mhest.com/supparticles/Honeybee-genome.pdf.

"By studying the humble honey bee, researchers at the University of Illinois at Urbana-Champaign have come a step closer to understanding the molecular basis of social behavior in humans."

“The honeybee (Apis mellifera) has been called a model system for social behavior,” said Saurabh (pronounced SAW-rub) Sinha, a professor of computer science and an affiliate of the university’s Institute for Genomic Biology. Using that model system, Sinha led a team that searched the honey bee genome for clues for social cues – a form of bee pressure that can cause bees to change jobs in response to needs of the hive."

“We want to learn how the honey bee society influences behavior in individual honey bees,” said Sinha, who is lead author of a paper that will be posted online this week ahead of regular publication by the Proceedings of the National Academy of Sciences. “By studying the social regulation of gene expression, we hope to extrapolate the biology to humans.”

"Adult worker bees perform a number of tasks in the hive when they are young, such as caring for eggs and larvae, and then shift to foraging for nectar and pollen as they age. However, if the hive has a shortage of foragers, some of the young nurse bees will switch jobs and become foragers."

"The job transition, whether triggered by age or social cues, involves changes in thousands of genes in the honey bee brain; some genes turn on, while others turn off."

"Genes are switched on and off by short strings of DNA that lie close to the gene. The strings serve as binding sites for particular molecules, called transcription factors. For example, when the correct transcription factor latches into the binding site, the gene may be switched on. If the transcription factor breaks away from the binding site, the gene is switched off."

"To search for genes that might play a role in social behavior, Sinha and his colleagues used the newly sequenced honey bee genome to scan the binding sites of transcription factors known to function in the development of fruit flies (Drosophila melanogaster) from a single cell to an adult."

"A computer algorithm written by the researchers scanned nearly 3,000 genes. Statistical techniques were then used to investigate whether particular transcription factors correlated with genes that were differentially expressed (turned on or off) between nurse bees and foragers."

“We found five different transcription factors that showed a statistically significant correlation with socially regulated genes,” Sinha said. “It appears that genes involved in nervous-system development in fruit flies are re-used by nature for behavioral functions in adult honey bees.”

"Their findings, Sinha said, suggest that honey bees will be useful in elucidating the mechanisms by which social factors regulate gene expression in brains, including those of humans."

source:http://news.illinois.edu/news/06/1023honeybees.html

No comments:

Visit GM Alexandra Kosteniuk's Women's Chess Blog:Please click on the image below:

Visit GM Alexandra Kosteniuk's Women's Chess Blog:Please click on the image below:
Chess needs more women and girl participants and administrators!

Thoughts worth thinking about

"Our subconscious minds have no sense of humor, play no jokes and cannot tell the difference between reality and an imagined thought or image. What we continually think about eventually will manifest in our lives."-Sidney Madwed



Laws alone can not secure freedom of expression; in order that every woman and man present their views without penalty, there must be spirit of tolerance in the entire population.- Albert Einstein Too often we underestimate the power of a touch, a smile, a kind word, a listening ear, an honest compliment, or the smallest act of caring, all of which have the potential to turn a life around. - Leo Buscaglia



A person's true wealth is the good he or she does in the world. - Mohammed



Our task must be to free ourselves... by widening our circle of compassion to embrace all living creatures and the whole of nature and its beauty. -Albert Einstein



The best way to find yourself, is to lose yourself in the service of others. - Ghandi



The unselfish effort to bring cheer to others will be the beginning of a happier life for ourselves. - Helen Keller



Aim for success, not perfection. Never give up your right to be wrong, because then you will lose the ability to learn new things and move forward with your life. Remember that fear always lurks behind perfectionism. Confronting your fears and allowing yourself the right to be human can, paradoxically, make yourself a happier and more productive person. - Dr. David M. Burns



Life is as dear to a mute creature as it is to man. Just as one wants happiness and fears pain, just as one wants to live and not die, so do other creatures. -His Holiness The Dalai Lama



Mankind's true moral test, its fundamental test (which lies deeply buried from view), consists of its attitude towards those who are at its mercy: animals. And in this respect mankind has suffered a fundamental debacle, a debacle so fundamental that all others stem from it. -



Milan Kundera, The Unbearable Lightness of Being



The worst sin towards our fellow creatures is not to hate them, but to be indifferent to them. That's the essence of inhumanity. -George Bernard Shaw

Ego's trick is to make us lose sight of our interdependence. That kind of ego-thought gives us a perfect justification to look out only for ourselves. But that is far from the truth. In reality we all depend on each other and we have to help each other. The husband has to help his wife, the wife has to help the husband, the mother has to help her children, and the children are supposed to help the parents too, whether they want to or not.-Gehlek Rinpoche Source: "The Best Buddhist Writing 2005 pg. 165

The hostile attitude of conquering nature ignores the basic interdependence of all things and events---that the world beyond the skin is actually an extension of our own bodies---and will end in destroying the very environment from which we emerge and upon which our whole life depends.