NPC2 Protein Mediates Chemical Communication in Worker Ants
Ants are eusocial insects that are found in most regions of the world. Within its caste, worker ants are responsible for various tasks that are required for colony maintenance.
In their chemical communication, α-helical carrier proteins, odorant-binding proteins, and chemosensory proteins, which accumulate in the sensillum lymph in the antennae, play essential roles in transferring hydrophobic semiochemicals to chemosensory receptors. It has been hypothesized that semiochemicals are recognized by α-helical carrier proteins.
The number of these proteins, however, is not sufficient to interact with a large number of semiochemicals estimated from chemosensory receptor genes.
Niemann - Pick type C2 protein was identified from the antenna of the worker Japanese carpenter ant, Camponotus japonicus (CjapNPC2). CjapNPC2 accumulated in the sensillum cavity in the basiconic sensillum. The ligand-binding pocket was composed of a flexible β-structure, which allowed binding to various potential semiochemicals, some of which elicited antennal electrophysiological responses. CjapNPC2 might be able to deliver various hydrophobic semiochemicals to chemosensory receptor neurons and plays crucial roles in chemical communication required to perform the worker ant tasks.
Carpenter ants are large ants indigenous to many parts of the world. They prefer dead, damp wood in which to build nests. They do not consume it, however, unlike termites. Sometimes carpenter ants will hollow out sections of trees. They also commonly infest wooden buildings and structures, and are a widespread nuisance and major cause of structural damage. The most likely species to be infesting a house in the United States is the black carpenter ant (Camponotus pennsylvanicus). However, there are over a thousand other species in the genus Camponotus.
How Ants Make Rafts to Save the Queen
Though scientists already knew about this strategy, little was known about the insects' decisions behind their raft-building process.
Now a study published February 19 in PLOS ONE shows that flood ants (Formica selysi) that live in the floodplains of Switzerland work together to protect the queen by strategically placing larvae, pupae, and worker ants at the bottom of the raft. The queen was placed in the center of the raft to shield her from water and other dangers.
This arrangement initially perplexed the scientists, since the bottom layer of the raft can be eaten by fish and swept away by turbulent waters.
"We were expecting the colonies to protect the most valuable members, the queen and young," said study leader Jessica Purcell, an ecologist at the University of Lausanne in Switzerland.
The short answer: The young ants are used as floating devices that are more efficient--that is, fewer lives lost--than older ants, Purcell explained.
Buoyant Babies NPC2 protein mediates chemical communication in worker ant Science & Technology World Website
By observing flood ants in the lab, the team found that when the water begins to rise, worker ants will grab any available larvae to use as a floatation device, and more ants pile on top of them. The queen is moved to the center early in the building process.
Young ants are more buoyant than worker ants, and the team discovered the young insectshave a lower risk of dying at the bottom of the boat than thought.
"The larvae and pupae are buoyant and not entirely submerged," said Purcell. "They are also quite fat, which may be one characteristic that helps buffer them against cold-water conditions."
Without larvae and pupae under the raft, 25 to 50 percent of the worker ants had at least partial contact with the water, putting more of them in danger.
Also, by strategically placing young ants at the bottom, the colony can quickly return to normal after the flood. That's because it takes more than an hour for submerged adult ants to recover from water exposure.
This isn't the first study to document the use of young at the bottom of ant rafts--other ant species build similar rafts--but it offers a new cost-benefit analysis of the behavior.
"Placing young on the base of the raft is a very efficient means of creating a highly buoyant raft," said Purcell, "and they achieve all this at minimal cost in terms of mortality."
sources: [http://en.twwtn.com/Bignews/60474.html]
In their chemical communication, α-helical carrier proteins, odorant-binding proteins, and chemosensory proteins, which accumulate in the sensillum lymph in the antennae, play essential roles in transferring hydrophobic semiochemicals to chemosensory receptors. It has been hypothesized that semiochemicals are recognized by α-helical carrier proteins.
The number of these proteins, however, is not sufficient to interact with a large number of semiochemicals estimated from chemosensory receptor genes.
Niemann - Pick type C2 protein was identified from the antenna of the worker Japanese carpenter ant, Camponotus japonicus (CjapNPC2). CjapNPC2 accumulated in the sensillum cavity in the basiconic sensillum. The ligand-binding pocket was composed of a flexible β-structure, which allowed binding to various potential semiochemicals, some of which elicited antennal electrophysiological responses. CjapNPC2 might be able to deliver various hydrophobic semiochemicals to chemosensory receptor neurons and plays crucial roles in chemical communication required to perform the worker ant tasks.
Carpenter ants are large ants indigenous to many parts of the world. They prefer dead, damp wood in which to build nests. They do not consume it, however, unlike termites. Sometimes carpenter ants will hollow out sections of trees. They also commonly infest wooden buildings and structures, and are a widespread nuisance and major cause of structural damage. The most likely species to be infesting a house in the United States is the black carpenter ant (Camponotus pennsylvanicus). However, there are over a thousand other species in the genus Camponotus.
How Ants Make Rafts to Save the Queen
Though scientists already knew about this strategy, little was known about the insects' decisions behind their raft-building process.
Now a study published February 19 in PLOS ONE shows that flood ants (Formica selysi) that live in the floodplains of Switzerland work together to protect the queen by strategically placing larvae, pupae, and worker ants at the bottom of the raft. The queen was placed in the center of the raft to shield her from water and other dangers.
This arrangement initially perplexed the scientists, since the bottom layer of the raft can be eaten by fish and swept away by turbulent waters.
"We were expecting the colonies to protect the most valuable members, the queen and young," said study leader Jessica Purcell, an ecologist at the University of Lausanne in Switzerland.
The short answer: The young ants are used as floating devices that are more efficient--that is, fewer lives lost--than older ants, Purcell explained.
Buoyant Babies NPC2 protein mediates chemical communication in worker ant Science & Technology World Website
By observing flood ants in the lab, the team found that when the water begins to rise, worker ants will grab any available larvae to use as a floatation device, and more ants pile on top of them. The queen is moved to the center early in the building process.
Young ants are more buoyant than worker ants, and the team discovered the young insectshave a lower risk of dying at the bottom of the boat than thought.
"The larvae and pupae are buoyant and not entirely submerged," said Purcell. "They are also quite fat, which may be one characteristic that helps buffer them against cold-water conditions."
Without larvae and pupae under the raft, 25 to 50 percent of the worker ants had at least partial contact with the water, putting more of them in danger.
Also, by strategically placing young ants at the bottom, the colony can quickly return to normal after the flood. That's because it takes more than an hour for submerged adult ants to recover from water exposure.
This isn't the first study to document the use of young at the bottom of ant rafts--other ant species build similar rafts--but it offers a new cost-benefit analysis of the behavior.
"Placing young on the base of the raft is a very efficient means of creating a highly buoyant raft," said Purcell, "and they achieve all this at minimal cost in terms of mortality."
sources: [http://en.twwtn.com/Bignews/60474.html]
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