The sea lamprey has a primordial accessory olfactory system

Steven Chang, Yu Wen Chung-Davidson, Scot V. Libants, Kaben G. Nanlohy, Matti Kiupel, Charles Brown, Weiming Li

Research output: Contribution to journalArticle

13 Scopus citations


Background: A dual olfactory system, represented by two anatomically distinct but spatially proximate chemosensory epithelia that project to separate areas of the forebrain, is known in several classes of tetrapods. Lungfish are the earliest evolving vertebrates known to have this dual system, comprising a main olfactory and a vomeronasal system (VNO). Lampreys, a group of jawless vertebrates, have a single nasal capsule containing two anatomically distinct epithelia, the main (MOE) and the accessory olfactory epithelia (AOE). We speculated that lamprey AOE projects to specific telencephalic regions as a precursor to the tetrapod vomeronasal system. Results: To test this hypothesis, we characterized the neural circuits and molecular profiles of the accessory olfactory epithelium in the sea lamprey (Petromyzon marinus). Neural tract-tracing revealed direct and reciprocal connections with the dorsomedial telencephalic neuropil (DTN) which in turn projects directly to the dorsal pallium and the rostral hypothalamus. High-throughput sequencing demonstrated that the main and the accessory olfactory epithelia have virtually identical profiles of expressed genes. Real time quantitative PCR confirmed expression of representatives of all 3 chemoreceptor gene families identified in the sea lamprey genome. Conclusion: Anatomical and molecular evidence shows that the sea lamprey has a primordial accessory olfactory system that may serve a chemosensory function.

Original languageEnglish (US)
Article number172
JournalBMC Evolutionary Biology
Issue number1
StatePublished - Aug 20 2013
Externally publishedYes


ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics

Cite this

Chang, S., Chung-Davidson, Y. W., Libants, S. V., Nanlohy, K. G., Kiupel, M., Brown, C., & Li, W. (2013). The sea lamprey has a primordial accessory olfactory system. BMC Evolutionary Biology, 13(1), [172].