Development for Termite Genomics
Srini Kambhampati, Entomology
Termites (Isoptera) are hemimetabolous eusocial insects that live in complex societies.
Termites exhibit eusociality not unlike that found in ants and some bees and wasps: caste
system, polyphenisms, multiple developmental pathways, complex communication, symbiosis
with protozoans and bacteria, construction and maintenance of complex nests, and use of
“agriculture.” Whereas kin selection explains the maintenance of eusociality in haplodiploid
Hymenoptera a comparable theory for termites, in which both sexes are diploid, is not
available. Since all extant termites are eusocial comparisons between non-eusocial and eusocial
taxa are not possible. Finally, termites differ in substantial ways from honey bees. Therefore,
genomic studies on termites are one of the few avenues left to obtain information on the genetic
basis of cooperation and social living and lead to comparative studies with evolutionarily
divergent honey bees, ants, and social wasps. Here, I outline a research plan to develop
genomic resources that will set the stage for sequencing of a termite genome. The specific
aims are: 1. Construct a BAC library from the termite Reticulitermes flavipes to 8X-10X coverage.
2. Sequence 10 randomly chosen BAC clones to obtain an initial characterization of the R.
flavipes genome. The genome size of R. flavipes using flowcytometry was estimated to be 1.03 Gb
distributed in 42 chromosomes. This research plan is complementary to an EST project currently
in progress in the PI’s laboratory. We have constructed 5 cDNA libraries from R. flavipes:
workers, soldiers, alates, larval stages 1-2, and larval stages 3-4; three more libraries are
planned. We have sequenced ~2,000 ESTs and ~7,800 clones have been sent for sequencing. We
plan to sequence an additional 12,000 ESTs in the next few months from the new and existing
cDNA libraries. A consortium of termite researchers has been assembled to collaboratively and
synergistically utilize the BAC and EST resources. These resources are expected to significantly
enhance the viability of a white paper for the termite genome sequencing and grant proposals to
USDA, NSF, and NIH. In the long term, they will help elucidate the interactions between genes,
behavior, and environment that together result in a highly complex society encompassing many
traits also observed in human societies.