Bart Lodder

Neuron classes are distinguished by expression of many genes, including those for ion channel subunits. In cortex, PV+ neurons are the major expressors of Kcng4, which encodes for the K-channel "silent" subunit Kv6.4. @SanikaGanesh led this work showing that Kv6.4 regulates

Not sure who is still out there but we're proud of this work led by @lodder_bart that (1) propose a new method to turn intensity sensors into lifetime sensors and (2) applies it to GCAMP8m to make an excellent lifetime Ca sensor. biorxiv.org/content/10.648…

5. We show, in behaving mice, that baseline calcium is correlated with the firing rate of individual neurons and that baseline calcium dynamically changes in response to visual stimulation and changes in firing rate

4. We show that LifeCamp allows for more accurate measurement of population activity, using fluorescence lifetime photometry at high temporal resolution (FLIPR). LifeCamp is insensitive to intensity artifacts and allows for the capture of long term changes in calcium levels.

We posted a new paper on biorxiv describing LifeCamp, a new high speed calcium lifetime sensor. LifeCamp enables detection of baseline calcium, neuronal firing and artifact insensitive comparisons across experiments, brain regions and long timescales. biorxiv.org/content/10.648…

Excited to share some of my PhD work out today in @NeuroCellPress! We use our novel lifetime photometry system with the new dLight3.8 sensor to study hunger induced changes in exploration and risk assessment derive from AgRP modulation of dopamine signaling in tail of striatum.

Our latest led by @TVKamath with important contributions by collaborators including Nao Uchida, Mitsuko Watabe-Uchida and @LinTianPhD Hunger modulates exploration through suppression of dopamine signaling in the tail of the striatum: Neuron cell.com/neuron/fulltex…

6/ Altogether, FLIPR allows for easy and robust absolute measurement of fast and slow neurotransmitter release and together with new lifetime sensors such as dLight3.8 will give neuroscientist new capabilities to measure neuronal signals for fundamental and disease research

5/ Finally, we developed a two-color FLIPR system, which allowed us to simultaneously record absolute dopamine and calcium in D1 receptor neurons in freely moving mice.

Our fluorescence lifetime photometry at high temporal resolution (FLIPR) paper is now online at Neuron. FLIPR allows for fast (10Hz-1 kHz) and slow (min-hrs) measurement of absolute neuronal signals in freely moving mice. We highlight the utility by measuring tonic and phasic DA.

@tpatriarchi Thank you for the suggestion! This chemogenetic tool is very useful and can be used simultaneously with FLIPR to boost the tonic signal. In order to claim absolute measurement one would have to of course very carefully characterize the stable regime of DETQ affinity modulation

@lodder_bart This is awesome! Congrats to the team. I am wondering if you'd find it interesting to combine your approach with chemogenetic potentiation of dLight: #Sec35" target="_blank" rel="nofollow noopener">nature.com/articles/s4146…

If you are interested how to measure absolute neurotransmitter release or neuronal signals in vivo over long time-scales and at high speed, please check out our new pre-print, where we use FLIPR to measure phasic and tonic dopamine in freely moving mice. biorxiv.org/content/10.110…

@yaochen20 Thank you Yao!

Important technology development to make fluorescence lifetime measurement much faster. Congratulations, Bart and team!

5/ In this preprint, we show that FLIPR is a powerful technology that will allow the community access to absolute fast and slow signal measurement in vivo. Thank you to my mentors @blsabatini Roger Adan, coauthors and Sabatini lab members