The lab of Nick Bellono, along with colleagues at UC San Diego and UT Southwestern Medical Center, recently published two papers in Nature describing the path of divergent sensing capabilities in cephalopods by tracking their evolutionary lineage from common ancestral neurons.

(l to r) Nick Bellono, Peter Kilian, Corey Allard, and Wendy Andrea Valencia-Montoya.
Image courtesy of Harvard’s Department of Molecular and Cellular Biology.

The first paper (first authors Corey Allard and Guipeun Kang) reveals with cryo-electron microscopy the structure of an octopus chemotactile receptor which is used by the animal’s arms for “taste by touch” exploration of the seafloor. Together with evolutionary, biophysical, and behavioral analyses, the team shows how strikingly novel structural adaptations facilitate the receptor’s transition from an ancestral role in neurotransmission to a new function in chemotactile sensation of poorly soluble environmental agonists.

The second paper (first authors Guipeun Kang, Corey Allard, and Wendy A Valencia-Montoya) takes a look at squid, which are cephalopods with a very different ambush predation strategy than the octopus. Here the team combines genetics, physiology, and behavior to discover a new class of an ancient chemotactile receptor that detects soluble bitter molecules, obtains its structure with a novel agonist bound, and performs evolutionary analyses to relate adaptations in squid receptors to more elaborate expansions in octopus. Together the two studies shed light on how subtle structural adaptations can drive new organismal behaviors suited to specific ecological contexts.

Read more on the MCB Department website and in the Harvard Gazette.