Fig. 1:
Communication between Japanese carpenter ants
Using one of the
antennae on its head, an ant accesses information
provided by
hydrocarbons on the body surface of another ant,
enabling nestmate
and caste recognition, and instruction
about occupational
tasks.
(August 28, 2015) A research group, involving Project
Assistant Professor HOJO Masaru, Associate Professor SAKURA Midori, and
Professor OZAKI Mamiko at Kobe University's Graduate School of Science and
researchers from the National Institute for Basic Biology, has identified
chemosensory proteins (CSPs) that play important roles in communications
between worker ants. CSPs may represent a starting point for elucidation of the
molecular mechanisms involved in the sophisticated system of communication that
supports ants' complex societies, and the evolution of these mechanisms. These
findings were published in Scientific Reports on August 27 (Japan time).
Ants, being social insects, form highly organized societies
on the basis of very close communication between individuals, mediated by
pheromones and other chemical substances. Information about the genomes of
several ant species has been obtained to date, and genes linked to
chemosensitivity in ants have been shown to be diverse. However, almost no
elucidation of the modes of expression and functioning of these genes in
chemosensory organs has previously been achieved.
This research group previously showed that one type of CSP1,
CjapCSP1, binds with cuticular hydrocarbons2 that play important roles in ant
inter-individual communication, and that this is linked to nestmate recognition
behavior by worker ants (Ozaki et al., 2005).
Fig. 2: Expression
loci of CSPs on antennae of Japanese carpenter ant workers
(A) Expression
loci of CjapCSP1 (green) and CjapCSP12 (red). (B) Expression loci of
CjapCSP1 (green)
and CjapCSP13 (red). (a) and (b) show magnified images of the
regions enclosed
by broken lines in (A) and (B), respectively.
Yellow indicates
regions where two genes are co-expressed at a single locus.
In the present research, Project Assistant Professor HOJO
Masaru’s research group extracted RNA from the antennae of the Japanese
carpenter ant (Camponotus japonicus), with support from the laboratory of INOUE
Kunio at Kobe University’s Biology Department, and comprehensively analyzed the
genes expressed on the antennae using a next-generation DNA-sequencer and
supercomputer at the National Institute for Basic Biology. The nucleotide
sequences of 11 novel CSPs were thus elucidated.