Properties of multi-vesicular release from mouse rod photoreceptors support transmission of single photon responses

C. L. Hays, A. L. Sladek, G. D. Field, Wallace B. Thoreson

Research output: Contribution to journalArticlepeer-review

Abstract

Vision under starlight requires rod photoreceptors transduce and transmit single photon responses to the visual system. Small single photon voltage changes must therefore cause detectable reductions in glutamate release. We found that rods achieve this by employing mechanisms that enhance release regularity and its sensitivity to small voltage changes. At the resting membrane potential in darkness, mouse rods exhibit coordinated and regularly timed multivesicular release events, each consisting of ~17 vesicles and occurring 2-3 times more regularly than predicted by Poisson statistics. Hyperpolarizing rods to mimic the voltage change produced by a single photon abruptly reduced the probability of multivesicular release nearly to zero with a rebound increase at stimulus offset. Simulations of these release dynamics indicate that this regularly timed, multivesicular release promotes transmission of single photon responses to post-synaptic rod bipolar cells. Furthermore, the mechanism is efficient, requiring lower overall release rates than uniquantal release governed by Poisson statistics. Impact Statement.

Original languageEnglish (US)
Article numbere67446
JournaleLife
Volume10
DOIs
StatePublished - Mar 2021

Keywords

  • Exocytosis
  • Glutamate transporter anion current
  • Mouse
  • Retina
  • Ribbon synapse
  • Rods
  • Vision

ASJC Scopus subject areas

  • Neuroscience(all)
  • Immunology and Microbiology(all)
  • Biochemistry, Genetics and Molecular Biology(all)

Fingerprint

Dive into the research topics of 'Properties of multi-vesicular release from mouse rod photoreceptors support transmission of single photon responses'. Together they form a unique fingerprint.

Cite this