Comments (0)

By Amro, December 6, 2011

Dr. Gro Amdam’s group wrote a perspective to accompany the lab’s first article on the evolution of the egg yolk protein in the bee.  We are very happy given that Dr. Amdam has literally written the egg yolk protein story for the honey bee over the past several years.

The full citation of the perspective is found below:

HAVUKAINEN, H., HALSKAU, Ø. and AMDAM, G. V. (2011), Social pleiotropy and the molecular evolution of honey bee vitellogenin. Molecular Ecology, 20: 5111–5113. doi: 10.1111/j.1365-294X.2011.05351.x

Comments (2)

By Amro, November 8, 2011

Congrats to Brock Harpur who won the 2011 Entomological Society of Canada’s President Prize in Biodiversity & Physiology! The award is given to the top graduate student presentation in the Biodiversity and Physiology section at the Entomological Society of Canada’s annual meeting held at Halifax.  Brock’s talk was titled “Diversity and Selection on the Honey Bee Immune System”.  Brock held a Natural Sciences and Engineering Research Council of Canada’s Julie Payette Scholarship in 2010, and currently holds an Ontario Graduate Scholarship.  Way to go Brock… We are all very proud!

Amro

Comments (0)

By Amro, November 4, 2011

The lab will be featured on next Monday’s (7th Nov 2011) episode of “A Greener York” on RogersTV.  You can view the interview online!

Comments (0)

By Amro, October 27, 2011

I am very happy to announce the first paper from the Zayed lab, recently published by journal Molecular Ecology, on the evolution of the egg-yolk protein in honey bees. As the name implies, egg-yolk proteins are used to provision animal eggs with the necessary proteins and fats.  The egg-yolk protein in honey bees is very interesting.  Queen honey bees are egg laying machines; they have massive ovaries and can lay 1,000+ eggs per day!  Queens make a lot of the egg-yolk protein to provision these eggs.  But workers bees are effectively sterile, so they do not need to make egg-yorlk proteins, right? Well, as it turns out, worker bees also synthesize egg-yolk protein but use it in a different way.  They use it to make food secretions which they spit out to feed younger bees.  Also, the egg-yolk protein interacts with an important hormone in workers to affect the way workers behave.  So, the egg-yolk protein affects both queen bee traits as well as worker bee traits. Now, imagine a new mutation in the egg-yolk protein… Can this mutation spread in honey bee populations given that the egg yolk protein is used differently in queens and workers? In other words, if a new mutation is good for the queen, is it also good (or neutral) for workers?  If this is the case, then we should see lots of signs of positive selection on the egg-york protein.  You can also imagine an alternative scenario – if a new mutation is good for workers but bad for queens (or vice versa), then we would expect the gene to show signs of ‘constraint’ – the protein is ‘stuck’ in evolutionary terms because it is being pulled in opposite directions by queens and workers.

Egg yolk protein (Vg) adaptively evolves in the bee, Y>0 indicates positive selection; (reproduced from Kent et al 2011)

We decided to test this idea by sequencing the egg-yolk protein, along with seven other genes (controls) in honey bees from Africa and Europe.  Two undergraduate Research At York students carried out the molecular biology work (Amer Issa and Alexandra Bunting, both co-authors on the paper), while NSERC Postdoctoral Fellow Dr. Clement Kent carried out the population genetic analyses. We found very high levels of adaptive evolution acting on the egg-yolk protein, supporting the idea that what is good for the Queen is also good (or at least neutral) for Workers!

Dr. Kent cleverly mapped all the functional mutations to the egg-yolk protein’s 3D structure.

He found that almost all of them line the internal cavity of the egg-yolk protein where lipids are ‘bound’.  This is very exciting as it suggest that mutations in the egg-yolk protein affect fitness in honey bees by changing the protein’s capacity to interact with lipids.  We’ll be following up on this in future studies.

Functional mutations in the egg yolk protein are associated with lipid binding (reproduced from Kent et al 2011)

As it turns out, many genes in the honey bee genome are active in both workers and queens, and our work suggests that this may not constrain adaptation in the bee. From a practical point of view, our results show that the activation of genes in both queens and workers need not hinder breeding efforts.  Beekeepers often breed colonies with good worker traits (e.g. good foraging, low aggression, good hygiene, etc.).  Our study suggests that mutations which benefit one caste do not often disadvantage the other.

Comments (0)

By Amro, September 28, 2011

I am very happy to announce that Clement Kent, a postdoctoral fellow in the lab, won the North American Pollinators Protection Campaign‘s 2011 Pollinator Advocate Award for Canada.  I can’t think of a more deserving individual; By day, Clement solves the mysteries of the honey bee’s genome, and by night (and on weekends), he works to develop pollinator gardens to help save the bees, the butterflies, and the birds!  Check out the press release and video interview and Clement’s pollinator garden blog.  Clement will also be on CBC Radio’s Here and Now later this afternoon (3:30-4:30 pm EST) [click here to hear it!].  Way to go Clement!

Comments (0)

By Amro, September 12, 2011

Amro Zayed will be giving departmental seminars at Ryerson University (Toronto, Ontario) on September 15th 2011, at Rochester University (NY, USA) on October 7th 2011, and at McMaster University (Hamilton, Ontario) on November 16th.

UPDATE: Come out and see Brock, Shermineh, Clement and Amro at the 148th Annual General Meeting for the Entomological Society of Ontario, Brock University in St. Catharines, October 21-23, 2011

The lab will also participate in the Entomological Society of Canada’s Joint Annual Meeting in Halifax Nova Scotia (Nov. 6-9 2011). Amro will give a seminar on the consequences of diploid males in bees/wasps/ants at the Female Mating Failure Symposium and on honey bee population and evolutionary genetics at the Pollinators and Pollination Symposium.  Graduate students Brock Harpur and Shermineh Minaei will also give talks about their research.

Comments (0)

By Amro, July 7, 2011

York University’s YFile ran a little news story on our research today – check it out here! They also posted a fun video of the lab on youtube.  [Shermineh, Alex, Jack, and Brock(‘s hands) make cameo appearances]

Comments (0)

By Amro, June 23, 2011

Recipe for making 120 super-sister queen bees:

1. Find one-day old larva, laid by the Queen Mum.  They are the small c-shaped grubs, about the same length as the rice-shaped eggs. At this stage, the caste of the female larva has not been ‘set’.

Egg is at the top left corner, 1-day old larva is at the bottom right corner

2. Gently scoop the larva out of the cell

Brock - the official grafter of the '11 Experiment

3. Transfer the larva to a plastic cell cup

Easy does it

4. Repeat 120 times
5. Hang the cell cups vertically  inside a strong queen-less colony. The worker bees will be eager to make a new queen to replace their missing mom –  they will feed the very young larva in the cups lots of royal jelly, which starts the queen development program.
6. Your queens will be ready in 12 days!

Comments (0)

By Amro, June 21, 2011

“Good afternoon your majesty! May i say that you look especially fecund today!”

There are thousands of workers and hundreds of drones in a honey bee colony, but only one queen.  She has massive ovaries and a long abdomen to deposit eggs into the hexagonal cells that workers build out of wax.  You can’t tell from the picture below, but queen number 3 (The Queen Mom) is very special …

First, a quick lesson on haplo-diploidy.  Humans, and most other animals, are diploid – both males and females have two sets of each chromosome inherited from mom and dad.  Bees, on the other hand, are haplo-diploid … females are diploid with two sets of each chromosome inherited from mom and dad, but males (=drones) are haploid – they only have one copy of each chromosome that they get from their mom.  How does this happen? A queen will fertilize her eggs with sperm to produce diploid daughters, but will lay unfertilized eggs to produce haploid sons.  So, a female bee (queen or worker) has a mom and a dad, but male bees only have a mom (but they still have a granddad from their mom’s side 🙂 )

Queen (3) surrounded by her retinue of workers

Second, a quick lesson on bee sex [put on some barry white while you read this next paragraph].  Normally, a virgin queen will go on a nuptial flight where she mates with 15 to 20 drones on the wing!!!  She stores sperm from all of her mates. When she starts fertilizing her eggs to make workers/daughter queens, something interesting happens: if two eggs get fertilized with sperm from different males, then the daughters will be ‘half sisters’ – they have the same mom, but different dads.  Alternatively, two eggs can get fertilized with sperm from the same male, which will give us ‘full sister’ that have the same mom and dad.  So, how related are full sisters and half sisters ? In humans, full siblings are 50% related and half siblings are 25% related. But because drones are haploid, they only have one copy of each chromosome that they pass to all of their daughters.  So, full sister bees share 100% of the genetic material they inherit from their dad and 50% of the genetic material they inherit from their mom – they are 75% related.  We call full sister bees “Super Sisters”, because they are super related!  This unusual genetic system makes for some very interesting consequences… for one, full sisters are more closely related to each other then to their own daughters… Neat!

The other great thing about super-sisters is that they make studying genetics a lot easier.  Because super sisters are very related (close to being clones of each other), they are used as a tool by researchers to virtually eliminate genetic variation from the mom’s side.  So, by mating many super-sister queens to different drones, we can see how different genetic mutations carried by drones can affect colony traits without having to worry about genetic variation in the queens.

Here is where the Queen Mom comes in!… We got the queen mom while she was still a virgin.  Then we artificially inseminated her with sperm from a single drone!  So, all of the Queen Mom’s daughters will be super sisters.  It took us more than a month to make the Queen Mom… now we are ready for the experiment !

Comments (0)

By Amro, May 24, 2011

Very happy to announce that Brock Harpur was recently awarded an Ontario Graduate Scholarship.  Brock joined the lab as a graduate student last fall on a Julie Payette Scholarship.  Congrats Brock!