9YI4 | pdb_00009yi4

Octopus sensory receptor CRT1 bound to Progesterone

PDB DOI: https://doi.org/10.2210/pdb9YI4/pdb
EM Map EMD-72977: EMDB EMDataResource

Classification: MEMBRANE PROTEIN
Organism(s): Octopus bimaculoides
Expression System: Homo sapiens
Mutation(s): No

Deposited: 2025-10-01 Released: 2026-04-01
Deposition Author(s): Jiang, H., Hibbs, R.E.
Funding Organization(s): National Institutes of Health/National Institute of Neurological Disorders and Stroke (NIH/NINDS)

Experimental Data Snapshot

Method: ELECTRON MICROSCOPY
Resolution: 2.80 Å
Aggregation State: PARTICLE
Reconstruction Method: SINGLE PARTICLE

wwPDB Validation 3D Report Full Report

This is version 1.2 of the entry. See complete history.

Literature

A sensory system for mating in octopus.

Villar, P.S., Jiang, H., Shugaeva, T., Berdan, E.L., Kulkarni, A., Hiroi, M., Masucci, G., Reiter, S., Lindahl, E., Howard, R.J., Hibbs, R.E., Bellono, N.W.

(2026) Science 392: 96-101

PubMed: 42012846 Search on PubMed
DOI: https://doi.org/10.1126/science.aec9652
Primary Citation Related Structures:
9YI4

PubMed Abstract:
Sensory systems for mate recognition maintain species boundaries and influence diversification. Thus, uncovering how molecules and receptors evolve to mediate this critical function is essential to understanding biodiversity. Male octopuses use a specialized arm called the hectocotylus to identify females and navigate their internal organs to reach the oviduct and deliver sperm. Here, we discovered that the hectocotylus is a dual sensory and mating organ that uses contact-dependent chemosensation of progesterone, a conserved ovarian hormone. We identified chemotactile receptors for progesterone and resolved the structural basis for their evolution from ancestral neurotransmitter receptors and subsequent expansion and tuning across cephalopods. These findings reveal principles by which sensory innovations shape reproductive behavior and suggest mechanisms for how sensory evolution contributes to the diversification of life.

Organizational Affiliation

Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, USA.

Macromolecule Content

Total Structure Weight: 243.77 kDa
Atom Count: 12,345
Modeled Residue Count: 1,460
Deposited Residue Count: 2,050
Unique protein chains: 1

Macromolecules

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| 3D Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Chemotactile receptor CRT1	A, B, C, D, E	410	Octopus bimaculoides	Mutation(s): 0 Gene Names: OCBIM_22006518mg
UniProt
Find proteins for A0A0L8FVQ9 (Octopus bimaculoides) Explore A0A0L8FVQ9 Go to UniProtKB: A0A0L8FVQ9
Entity Groups
Sequence Clusters	30% Identity 50% Identity 70% Identity 90% Identity 95% Identity 100% Identity
UniProt Group	A0A0L8FVQ9
Glycosylation
Glycosylation Sites: 5	Glycosylation Focus chain A Focus chain B Focus chain C Focus chain D Focus chain E
Sequence Annotations Expand
Reference Sequence

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram	3D Interactions
STR (Subject of Investigation/LOI) Query on STR Download:Ideal Coordinates CCD File SDF format, chain W [auth C] SDF format, chain Q [auth B] SDF format, chain K [auth A] SDF format, chain DA [auth E] SDF format, chain CA [auth D] MOL2 format, chain W [auth C] MOL2 format, chain Q [auth B] MOL2 format, chain K [auth A] MOL2 format, chain DA [auth E] MOL2 format, chain CA [auth D] mmCIF format, chain W [auth C] mmCIF format, chain Q [auth B] mmCIF format, chain K [auth A] mmCIF format, chain DA [auth E] mmCIF format, chain CA [auth D]	CA [auth D], DA [auth E], K [auth A], Q [auth B], W [auth C]	PROGESTERONE C₂₁ H₃₀ O₂ RJKFOVLPORLFTN-LEKSSAKUSA-N		Interactions Focus chain CA [auth D] Focus chain DA [auth E] Focus chain K [auth A] Focus chain Q [auth B] Focus chain W [auth C] Interactions & Density Focus chain CA [auth D] Focus chain DA [auth E] Focus chain K [auth A] Focus chain Q [auth B] Focus chain W [auth C]
NAG Query on NAG Download:Ideal Coordinates CCD File SDF format, chain Z [auth D] SDF format, chain Y [auth D] SDF format, chain X [auth D] SDF format, chain V [auth C] SDF format, chain U [auth C] SDF format, chain T [auth C] SDF format, chain S [auth C] SDF format, chain R [auth C] SDF format, chain P [auth B] SDF format, chain O [auth B] SDF format, chain N [auth B] SDF format, chain M [auth B] SDF format, chain L [auth B] SDF format, chain J [auth A] SDF format, chain IA [auth E] SDF format, chain I [auth A] SDF format, chain HA [auth E] SDF format, chain H [auth A] SDF format, chain GA [auth E] SDF format, chain G [auth A] SDF format, chain FA [auth E] SDF format, chain F [auth A] SDF format, chain EA [auth E] SDF format, chain BA [auth D] SDF format, chain AA [auth D] MOL2 format, chain Z [auth D] MOL2 format, chain Y [auth D] MOL2 format, chain X [auth D] MOL2 format, chain V [auth C] MOL2 format, chain U [auth C] MOL2 format, chain T [auth C] MOL2 format, chain S [auth C] MOL2 format, chain R [auth C] MOL2 format, chain P [auth B] MOL2 format, chain O [auth B] MOL2 format, chain N [auth B] MOL2 format, chain M [auth B] MOL2 format, chain L [auth B] MOL2 format, chain J [auth A] MOL2 format, chain IA [auth E] MOL2 format, chain I [auth A] MOL2 format, chain HA [auth E] MOL2 format, chain H [auth A] MOL2 format, chain GA [auth E] MOL2 format, chain G [auth A] MOL2 format, chain FA [auth E] MOL2 format, chain F [auth A] MOL2 format, chain EA [auth E] MOL2 format, chain BA [auth D] MOL2 format, chain AA [auth D] mmCIF format, chain Z [auth D] mmCIF format, chain Y [auth D] mmCIF format, chain X [auth D] mmCIF format, chain V [auth C] mmCIF format, chain U [auth C] mmCIF format, chain T [auth C] mmCIF format, chain S [auth C] mmCIF format, chain R [auth C] mmCIF format, chain P [auth B] mmCIF format, chain O [auth B] mmCIF format, chain N [auth B] mmCIF format, chain M [auth B] mmCIF format, chain L [auth B] mmCIF format, chain J [auth A] mmCIF format, chain IA [auth E] mmCIF format, chain I [auth A] mmCIF format, chain HA [auth E] mmCIF format, chain H [auth A] mmCIF format, chain GA [auth E] mmCIF format, chain G [auth A] mmCIF format, chain FA [auth E] mmCIF format, chain F [auth A] mmCIF format, chain EA [auth E] mmCIF format, chain BA [auth D] mmCIF format, chain AA [auth D]	AA [auth D] BA [auth D] EA [auth E] F [auth A] FA [auth E] AA [auth D], BA [auth D], EA [auth E], F [auth A], FA [auth E], G [auth A], GA [auth E], H [auth A], HA [auth E], I [auth A], IA [auth E], J [auth A], L [auth B], M [auth B], N [auth B], O [auth B], P [auth B], R [auth C], S [auth C], T [auth C], U [auth C], V [auth C], X [auth D], Y [auth D], Z [auth D]	2-acetamido-2-deoxy-beta-D-glucopyranose C₈ H₁₅ N O₆ OVRNDRQMDRJTHS-FMDGEEDCSA-N		Interactions Focus chain AA [auth D] Focus chain BA [auth D] Focus chain EA [auth E] Focus chain F [auth A] Focus chain FA [auth E] Focus chain G [auth A] Focus chain GA [auth E] Focus chain H [auth A] Focus chain HA [auth E] Focus chain I [auth A] Focus chain IA [auth E] Focus chain J [auth A] Focus chain L [auth B] Focus chain M [auth B] Focus chain N [auth B] Focus chain O [auth B] Focus chain P [auth B] Focus chain R [auth C] Focus chain S [auth C] Focus chain T [auth C] Focus chain U [auth C] Focus chain V [auth C] Focus chain X [auth D] Focus chain Y [auth D] Focus chain Z [auth D] Interactions & Density Focus chain AA [auth D] Focus chain BA [auth D] Focus chain EA [auth E] Focus chain F [auth A] Focus chain FA [auth E] Focus chain G [auth A] Focus chain GA [auth E] Focus chain H [auth A] Focus chain HA [auth E] Focus chain I [auth A] Focus chain IA [auth E] Focus chain J [auth A] Focus chain L [auth B] Focus chain M [auth B] Focus chain N [auth B] Focus chain O [auth B] Focus chain P [auth B] Focus chain R [auth C] Focus chain S [auth C] Focus chain T [auth C] Focus chain U [auth C] Focus chain V [auth C] Focus chain X [auth D] Focus chain Y [auth D] Focus chain Z [auth D]