A Caltech Library Service

Electrophysiology and transcriptomics reveal two photoreceptor classes and complex visual integration in Hirudo verbana

Stowasser, Annette and Stahl, Aaron and Benoit, Joshua B. and Wagenaar, Daniel A. (2019) Electrophysiology and transcriptomics reveal two photoreceptor classes and complex visual integration in Hirudo verbana. . (Unpublished)

[img] PDF - Submitted Version
Creative Commons Attribution Non-commercial No Derivatives.


Use this Persistent URL to link to this item:


Among animals with complex visual processing mechanisms, the leech Hirudo verbana is a rare example in which all neurons can be identified. However, little is known about its visual system, which is composed of several pigmented head eyes and photosensitive non-pigmented sensilla that are distributed across its entire body. Although several interneurons are known to respond to visual stimuli, their response properties are poorly understood. Among these, the S cell system is especially intriguing: It is multimodal, spans the entire body of the leech, and is thought to be involved in complex sensory integration. To improve our understanding of the role of this system, we tested its spectral sensitivity, spatial integration, and adaptation properties. The response of the S cell system to visual stimuli was found to be strongly dependent on the size of the area stimulated, and adaptation was local. Furthermore, a "bleaching experiment" demonstrated that at least two color channels contributed to the response, and that their contribution was dependent on the adaptation to the background. The existence of at least two color channels was further supported by transcriptomic evidence, which indicated the existence of at least two distinct groups of putative opsins for leeches. Taken together, our results show that the S cell system has highly sophisticated response properties, and could be involved in the processing of complex visual stimuli. We propose the leech as a novel system to understand visual processing mechanisms with many practical advantages.

Item Type:Report or Paper (Discussion Paper)
Related URLs:
URLURL TypeDescription Paper
Wagenaar, Daniel A.0000-0002-6222-761X
Alternate Title:Photoreceptors and integration in H. verbana
Additional Information:The copyright holder for this preprint is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under a CC-BY-NC-ND 4.0 International license. bioRxiv preprint first posted online Feb. 15, 2019. We wish to thank Elke Buschbeck and John Layne for the use of equipment and lab space. The authors declare no competing interests. Funding was provided by the National Institute of Neurological Disorders and Stroke (NS094403, to DAW) and by the BurroughsWellcome Foundation in the form of a Career Award at the Scientific Interface (to DAW). Data availability: Illumina sequencing files have been deposited to the NCBI SRA (Bioproject: PRJNA504032). Electrophysiology data and code used for analysis is available upon reasonable request.
Funding AgencyGrant Number
Burroughs Wellcome FundUNSPECIFIED
National Institute of Neurological Disorders and Stroke (NINDS)UNSPECIFIED
Subject Keywords:Invertebrate vision; opsins; visual integration; Medicinal leech; Hirudo verbana
Record Number:CaltechAUTHORS:20190219-112051503
Persistent URL:
Official Citation:Electrophysiology and transcriptomics reveal two photoreceptor classes and complex visual integration in Hirudo verbena. Annette Stowasser, Aaron Stahl, Joshua B Benoit, Daniel A Wagenaar. bioRxiv 552018; doi:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:92975
Deposited By: Tony Diaz
Deposited On:19 Feb 2019 22:25
Last Modified:19 Feb 2019 22:25

Repository Staff Only: item control page