Queen mandibular pheromone, or QMP, is a honey bee
pheromone
A pheromone () is a secreted or excreted chemical factor that triggers a social response in members of the same species. Pheromones are chemicals capable of acting like hormones outside the body of the secreting individual, to affect the behavio ...
produced by the
queen
Queen or QUEEN may refer to:
Monarchy
* Queen regnant, a female monarch of a Kingdom
** List of queens regnant
* Queen consort, the wife of a reigning king
* Queen dowager, the widow of a king
* Queen mother, a queen dowager who is the mother ...
and fed to her attendants who share it with the rest of the colony that gives the colony the sense of belonging to the queen. Newly emerged queens produce very little QMP. By the sixth day they are producing enough to attract drones for mating. A laying queen makes twice that amount. Lack of QMP seems to attract robber bees. A study of foraging worker bees has suggested that foraging bees are not attracted to QMP.
Chemical composition
Chemically, QMP is very diverse, with at least 17 major components and other minor ones. Five of these compounds are: 9-oxo-2-decenoic acid (9ODA), ''cis''- and ''trans''-9-hydroxydec-2-enoic acid (9HDA),
methyl ''p''-hydroxybenzoate (HOB) and 4-hydroxy-3-methoxyphenylethanol (HVA).
Drones
QMP functions as a
sex pheromone
Sex pheromones are pheromones released by an organism to attract an individual of the same species, encourage them to mate with them, or perform some other function closely related with sexual reproduction.
Sex pheromones specifically focus on ind ...
for drones, attracting males to an unmated queen. 9ODA specifically is known to attract drones over long distances, and its combination with 9HDA and 10HDA at close range increases drone attraction to the queen.
Drone detection of 9ODA begins in the
antennae, triggering a pathway that leads to behavioral responses. This begins with diffusion of 9ODA through the antennae's pores, into the
lymph
Lymph (from Latin, , meaning "water") is the fluid that flows through the lymphatic system, a system composed of lymph vessels (channels) and intervening lymph nodes whose function, like the venous system, is to return fluid from the tissues ...
of the olfactory sensillum. The
hydrophilic
A hydrophile is a molecule or other molecular entity that is attracted to water molecules and tends to be dissolved by water.Liddell, H.G. & Scott, R. (1940). ''A Greek-English Lexicon'' Oxford: Clarendon Press.
In contrast, hydrophobes are ...
domain of carrier protein ASP1 binds to an apolar region of 9ODA, forming a complex that is transported to olfactory receptors located in the
olfactory receptor neuron
An olfactory receptor neuron (ORN), also called an olfactory sensory neuron (OSN), is a sensory neuron within the olfactory system.
Structure
Humans have between 10 and 20 million olfactory receptor neurons (ORNs). In vertebrates, ORNs are b ...
s (ORNs).
Olfactory receptor ''Am''OR11 specifically is involved in responding to the pheromone/carrier complex. Although expressed in all
castes
Caste is a form of social stratification characterised by endogamy, hereditary transmission of a style of life which often includes an occupation, ritual status in a hierarchy, and customary social interaction and exclusion based on cultura ...
, expression of ''Am''OR11 is significantly higher in drones, further suggesting its role in 9ODA detection. The binding of the pheromone/carrier to ''Am''OR11 sends a signal to the brain's primary olfactory centres. The specific neural pathway by which 9ODA causes behavioral changes is not yet developed in bees, however research shows olfactory signals from floral odors are integrated to the level of
mushroom bodies
The mushroom bodies or ''corpora pedunculata'' are a pair of structures in the brain of insects, other arthropods, and some annelids (notably the ragworm ''Platynereis dumerilii''). They are known to play a role in olfactory learning and memory ...
. Research has not been conducted for the 9ODA pathway.
Workers
Components of QMP also function as a retinue pheromone, causing retinue behavioral and physiological changes in the female worker bees. Changes in QMP's chemical composition following a queen's mating attracts young worker bees to her, fulfilling her feeding and grooming requirements. QMP is transferred through contact from the queen to young workers, and in turn to the rest of the hive's workers. In doing so, the queen elicits behavioral changes in remaining workers, preventing the rearing of new queens, and preventing ovary development.
Behavioral changes in the workers as a result of QMP exposure is thought to be mediated through changes in juvenile hormone (JH) level. 9ODA specifically leads to changes in the endocrine organs, via the brain's mushroom bodies. QMP moderates the decrease in JH synthesis in young bees, preventing foraging behaviour.
Queen retinue pheromone
Slessor (2005) differentiates QMP from
queen retinue pheromone Queen retinue pheromones (QRP) are a type of honey bee pheromones, so-called because one of their behavioral effects is to attract a circle of bees (a “retinue”) around the queen.
In older literature, the queen pheromone is called ''mandibular ...
, on the basis of three fatty-acid constituents which are not derived from the mandibular gland.
Beekeeping
Sometimes beekeepers re-queen their hives for various reasons. Some beekeepers place these now-unneeded queens in alcohol. The alcohol preserves the deceased queen and her pheromones. This "queen juice" can then be used as a lure in swarm traps. The dead queen is either placed in a swarm trap or a q-tip or cottonball dipped in the alcohol into a swarm trap. The alcohol evaporates, leaving the queen pheromone which may enhance the chances of a swarm moving into a trap.
References
{{reflist
Pheromones
Beekeeping
Insect pheromones
Semiochemicals