Journal News

MCP: We shall know
thine enemy, honey bee

John Arnst
November 01, 2017

Varroa destructor is appropriately named, given the havoc it wreaks on colonies of western honey bees. Since it first arrived in Florida in the 1980s, the parasitic mite has pushed bee colonies across North America to ruin, and it is believed to be the most significant contributor to the recent spike in colony deaths in the United States and Canada. Despite the scope of the mite’s damage, however, surprisingly little is known about its inner molecular workings.

A western honey bee rests on a flower. RICKS/WIKIMEDIA COMMONS

As a first step in ultimately combating this bee-barian, researchers in the lab of Leonard Foster at the University of British Columbia in Canada have published a protein atlas in Molecular & Cellular Proteomics that details 1,433 differentially expressed proteins across the various developmental stages of V. destructor.

“One thing that a lot of people who are studying model systems or human systems don’t really appreciate is that when you move outside of those model systems and try to understand something at a molecular level about an organism without that huge body of knowledge that has been built over the years in that particular organism, you really don’t have any idea where to start,” Foster said. With this in mind, Foster and colleagues, including graduate student Alison McAfee, set out to create a document of the entire proteome that the male and female mites might produce throughout their life cycles.

“It’s a tool that other researchers can use to come up with their own questions about Varroa biology,” said McAfee, whose research focuses on the defense mechanisms bees mount against the mites.

In addition to quantifying the mites’ proteins, the researchers found that males and females expressed proteins involved in chromatin remodeling differently.

“Very little is known about the sex determination system in Varroa,” McAfee said. “Part of what that might be pointing to is the mites exposing different parts of the DNA to express more sex-specific proteins.”

The harm that V. destructor inflicts on honey bees is multifold; in addition to feasting on the bees’ blood and leaving open wounds ripe for infection, the mites are vectors for the deformed wing virus, which cripples wing growth in developing honey-bee pupae.

The scope of damage from mites is a consequence of abrupt introductions — the longer a host and parasite have coexisted and coevolved, the more harmonious, if still exploitative, their relationship will be.

Such is the case with V. destructor and its original host, the Asian honey bee, which have had millions of years to get to know one another. However, V. destructor and its viruses have just barely begun to make evolutionary introductions with honey bees, giving their new hosts few genetic weapons to fight them off.

According to Foster, Varroa’s use of odorant-binding proteins is likely key to their predatory interactions.

“Varroa have to be able to detect bees of certain ages, and this has to depend on odors,” he said. “At some point, we will want to try to define the molecular mechanism that is underlying that interaction, and knowing which proteins are expressed in which stages in the Varroa will be important for that eventual understanding.”

John Arnst

John Arnst is a science writer for ASBMB Today.

Join the ASBMB Today mailing list

Sign up to get updates on articles, interviews and events.

Latest in Science

Science highlights or most popular articles

A deeper insight into phospholipid biosynthesis in Gram-positive bacteria
Lipid News

A deeper insight into phospholipid biosynthesis in Gram-positive bacteria

February 18, 2020

Diego Sastre and Marcelo Guerin look at how membrane fluidity modulates the insertion of a peripheral enzyme to regulate bacterial phospholipid synthesis.

For vulnerable populations, the thorny ethics of genetic data collection
Feature

For vulnerable populations, the thorny ethics of genetic data collection

February 17, 2020

To be equitable, genetics research needs more diverse samples. But collecting that data could present ethical issues.

Anthrax vs. cancer
News

Anthrax vs. cancer

February 16, 2020

R. Claudio Aguilar explains how he joined forces with other labs in using a modified strain of anthrax to shrink tumors in dogs with terminal bladder cancer.

From the journals: JLR
Journal News

From the journals: JLR

February 11, 2020

Recent topics include interactions of the endocannabinoid pathway with the gut microbiome.

Selenium led Zhao from icy hometown to German hospitality
Award

Selenium led Zhao from icy hometown to German hospitality

February 09, 2020

JBC/Tabor award winner Wenchao Zhao studies Keshan disease, a nutrient deficiency named for the county in northeastern China where he grew up.

Dagar dissects a prostate cancer driver
Award

Dagar dissects a prostate cancer driver

February 08, 2020

This JBC/Tabor award winner has found a way to block androgen signaling in prostate cancer cells.